Delete .gitea/workflows/recover.yaml

Adjust tests to match current completion item labels and clean up formatting:
- Expect "nocomplain" (no leading dash) for the unset option case instead of {"-nocomplain", "--"}.
- Reflow several multi-line source literals into single-line/f-string forms.
- Normalize various assertions and generator expressions onto single lines.
- Reformat TextDocumentItem construction for readability.

These changes are limited to test code and reflect the updated shape/labels of completion items and stylistic cleanup; no production logic is modified.

.vscode/launch.json

@@ -39,6 +39,48 @@
             "autoAttachChildProcesses": true,
             "preLaunchTask": "NX Post Support: Compile Debug"
         },
+        {
+            // Linux workaround: js-debug's extensionHost attach probes localhost and [::1]
+            // in parallel and aborts when [::1] is refused. Start the dev host ourselves
+            // with a fixed inspector port and attach directly to 127.0.0.1.
+            "name": "Run Extension (Linux)",
+            "type": "node",
+            "request": "attach",
+            "address": "127.0.0.1",
+            "port": 9333,
+            "timeout": 30000,
+            "continueOnAttach": true,
+            "sourceMaps": true,
+            "outFiles": ["${workspaceFolder}/dist/**/*.js"],
+            "resolveSourceMapLocations": [
+                "${workspaceFolder}/dist/**/*.js",
+                "!**/node_modules/**"
+            ],
+            "skipFiles": ["<node_internals>/**"],
+            "preLaunchTask": "NX Post Support: Start Dev Host (Linux)"
+        },
+        {
+            "name": "Debug Extension (Linux, hidden)",
+            "type": "node",
+            "request": "attach",
+            "address": "127.0.0.1",
+            "port": 9333,
+            "timeout": 30000,
+            "continueOnAttach": true,
+            "sourceMaps": true,
+            "outFiles": ["${workspaceFolder}/dist/**/*.js"],
+            "resolveSourceMapLocations": [
+                "${workspaceFolder}/dist/**/*.js",
+                "!**/node_modules/**"
+            ],
+            "skipFiles": ["<node_internals>/**"],
+            "preLaunchTask": "NX Post Support: Start Dev Host with debugpy (Linux)",
+            "presentation": {
+                "hidden": true,
+                "group": "",
+                "order": 4
+            }
+        },
         {
             "name": "Python Attach",
             "type": "debugpy",
@@ -118,6 +160,16 @@
                 "group": "",
                 "order": 1
             }
+        },
+        {
+            "name": "Debug Extension and Python (Linux)",
+            "configurations": ["Python debug server (hidden)", "Debug Extension (Linux, hidden)"],
+            "stopAll": true,
+            "presentation": {
+                "hidden": false,
+                "group": "",
+                "order": 2
+            }
         }
     ]
 }

.vscode/tasks.json

@@ -28,6 +28,47 @@
                 "panel": "dedicated",
                 "clear": true
             }
+        },
+        {
+            "label": "NX Post Support: Start Dev Host (Linux)",
+            "detail": "Opens the Extension Development Host with the inspector on 127.0.0.1:9333 (workaround for js-debug localhost/::1 attach bug).",
+            "type": "shell",
+            "command": "\"$(dirname \"${execPath}\")/bin/$(basename \"${execPath}\")\" --new-window --inspect-brk-extensions=9333 --extensionDevelopmentPath=\"${workspaceFolder}\" \"${workspaceFolder}\" \"${workspaceFolder}/test/postprocessor\"",
+            "options": {
+                "shell": {
+                    "executable": "/bin/bash",
+                    "args": ["-c"]
+                }
+            },
+            "dependsOn": "NX Post Support: Compile Debug",
+            "problemMatcher": [],
+            "presentation": {
+                "reveal": "silent",
+                "panel": "dedicated"
+            }
+        },
+        {
+            "label": "NX Post Support: Start Dev Host with debugpy (Linux)",
+            "detail": "Same as above, but the language server connects to the debugpy listener on 127.0.0.1:5678.",
+            "type": "shell",
+            "command": "\"$(dirname \"${execPath}\")/bin/$(basename \"${execPath}\")\" --new-window --inspect-brk-extensions=9333 --extensionDevelopmentPath=\"${workspaceFolder}\" \"${workspaceFolder}\" \"${workspaceFolder}/test/postprocessor\"",
+            "options": {
+                "shell": {
+                    "executable": "/bin/bash",
+                    "args": ["-c"]
+                },
+                "env": {
+                    "USE_DEBUGPY": "True",
+                    "NXPS_DEBUG_HOST": "127.0.0.1",
+                    "NXPS_DEBUG_PORT": "5678"
+                }
+            },
+            "dependsOn": "NX Post Support: Compile Debug",
+            "problemMatcher": [],
+            "presentation": {
+                "reveal": "silent",
+                "panel": "dedicated"
+            }
         }
     ]
 }

CHANGELOG.md

@@ -1,51 +1,313 @@
+# Changelog
+
+All notable changes to NX Postprocessor Support are listed here, newest release first.
+Versions correspond to the Git tags of this repository.
+
 ## Unreleased
 
-- Add Go to Definition for TclOO classes, constructors, and resolved methods, including PSC library definitions
-- Index PSC layer scripts (including external paths and legacy Windows encoding) and share TclOO class metadata across files for completion, signatures, inlay hints, and highlighting
-- Add document-local TclOO method completion for `new`/`create` instances, `my`, and statically inferred return chains
+### Added
+
+- Go to Definition from block template and address arguments in Tcl (`MOM_do_template`, `MOM_force`, `MOM_suppress`, `MOM_ask_address_value`, ...) to the `BLOCK_TEMPLATE`/`ADDRESS` declaration in the PSC `.def` files
+- Hover over block templates shows the template body; hover over addresses shows format, leader, trailer, min/max, and modality
+- Find References and Rename for block templates and addresses across Tcl and `.def` files, including addresses used inside block templates
+- Go to Definition, hover, references, and rename also work inside `.def` files
+
+### Documentation
+
+- Document DEF block templates, addresses, `BLOCK_LIST`/`ADDR_LIST`, and the formatting changes in the README
+
+## [2026.9.700] - 2026-09-24
+
+### Added
+
+- `BLOCK_LIST` and `ADDR_LIST` completion keywords that list all loaded block templates or addresses; the keyword is replaced by the selected quoted name
+
+### Changed
+
+- Format comments with a space after `#` (`#Comment` becomes `# Comment`); `##` separators, `#!`, and comments that already start with whitespace stay unchanged
+
+## [2026.9.600] - 2026-09-24
+
+### Added
+
+- Read `BLOCK_TEMPLATE` and `ADDRESS` names from the `.def` files listed under `<DefinedEvents>` in PSC layers; changes to PSC and DEF files are picked up automatically
+- Suggest block templates for `MOM_do_template` and addresses for `MOM_ask_address_value`, `MOM_force`, and `MOM_suppress`, each followed by variables
+- Suggest `Always`, `Once`, and `Off` for the first argument of `MOM_force` and `MOM_suppress`
+- Insert block templates, addresses, and modes in quotes without doubling typed or auto-closed quotes; insert variables with a leading `$`
+- Persistent workspace index in the extension storage, so restarts skip reparsing unchanged files; the cache is discarded automatically when the server or bundled tclint changes
+
+### Changed
+
+- Reparse only the top-level Tcl commands touched by an edit instead of the whole file
+- Speed up TclOO completion, signature help, inlay hints, and Go to Definition by reusing the cached syntax tree and skipping files without classes
+- Speed up references, document highlights, and call hierarchy with cached definition lookups
+- Keep background indexing from blocking requests that need a fresh syntax tree
+
+### Fixed
+
+- Format and lint `uplevel` bodies as Tcl scripts instead of leaving them untouched
+- Stop the Python debug bootstrap with a clear error instead of hanging when no debugpy listener or only a stale one is available
+
+## [2026.9.501] - 2026-09-21
+
+### Fixed
+
+- Highlight braced stored-procedure names in `lappend` arguments
+
+## [2026.9.500] - 2026-09-21
+
+### Added
+
+- Index Tcl scripts referenced by PSC layers, including external folders, environment-variable folders, and legacy Windows encoding
+- Share TclOO class metadata across files for completion, signature help, inlay hints, and highlighting
+- Go to Definition for TclOO classes, constructors, and resolved methods, including PSC library definitions
+- CDL event handler snippets declare an extra `<var>_defined` global for parameters marked `TOGGLE Off`
+- Allow `INVALID` in the CDL `CATEGORY` grammar
+
+## [2026.9.400] - 2026-09-11
+
+### Added
+
+- Document-local TclOO method completion for `new`/`create` instances, `my`, and statically inferred return chains
+- Signature help and parameter inlay hints for resolved TclOO methods and constructors, including optional and variadic arguments
 - Suggest TclOO class names as classes and semantically highlight their declarations and calls
-- Show signature help and parameter inlay hints for resolved TclOO methods and constructors, including optional and variadic arguments
-- Add incoming and outgoing call hierarchy for custom TCL procedures and MOM event handlers
-- Add document highlights for procedure and variable occurrences
-- Make completion context-aware and prioritize local, current-file, workspace, and built-in symbols
-- Add command-aware completion for Tcl subcommands, fixed arguments, and valid options
-- Add semantic argument completion for variables, procedures, namespaces, and local file paths
-- Add placeholder-based snippets for common Tcl structures and `dict for`
-- Integrate the NX Tcl Remote Debugger directly into NX Postprocessor Support
-- Add `nx-tcl` attach configurations and breakpoint support for TCL and DEF files
-- Support breakpoints, stepping, stack frames, variables, watches, evaluation, logpoints, hit conditions, and Tcl error stops
-- Add generation-safe stack and variable references so delayed VS Code requests cannot address stale NX frames
-- Add command-buffer breakpoint handling for `LIB_GE_command_buffer_edit_*` source bodies
-- Extend the README with launch configuration, path mapping, and debugger usage
-- Prevent truncated TCL inlay hints and add configurable parameter hint modes
-- Add inlay hints for built-in NX procedures, variadic arguments, and visible ranges
-- Add inlay hint documentation and navigation to custom procedure definitions
-- Add signature help for custom TCL procedures and built-in NX/MOM procedures
-- Clean stale TCL indexes on close, delete, and rename operations
-- Make background parsing and index updates thread-safe
-- Improve TCL response times with debounced edits and cached semantic, inlay, hover, completion, and variable indexes
-- Debounce CDL/DEF diagnostics and remove per-line diagnostic logging
+- Keep completion working while the file has syntax errors
 
-## [0.0.1]
+## [2026.9.300] - 2026-09-10
 
-- Initial release
+### Added
 
-## [0.0.2]
+- Array key completion, including keys built with substitutions
+- Generated CDL event handler snippets declare `args`
 
-- Add Autocomp for TYPE
+## [2026.9.220] - 2026-09-08
 
-## [0.1.0]
+### Fixed
 
-- Add Hover Feature
+- Completion inside unfinished braced arguments now recognizes nested commands
 
-## [0.2.0]
+## [2026.9.210] - 2026-09-04
 
-- Add DEF File Support
+### Added
 
-## [2026.6.100]
+- Highlight escaped quoted strings and embedded variables in DEF files
 
-- Fix several bugs
+## [2026.9.200] - 2026-09-03
 
-## [2026.6.200]
+### Added
 
-- Fix foramtting bug
+- Command-aware completion for Tcl subcommands, fixed argument values, and options such as `string compare -nocase`
+- Semantic argument completion for variables, procedures, namespaces, and local file paths
+- Placeholder-based snippets for `if`, `foreach`, `proc`, `switch`, `try`, and `dict for`
+
+## [2026.9.100] - 2026-09-03
+
+### Added
+
+- Incoming and outgoing call hierarchy for custom Tcl procedures and MOM event handlers
+- Document highlights for procedure and variable occurrences
+- Context-aware completion that ranks local, current-file, workspace, and built-in symbols in that order
+
+### Changed
+
+- Update lsprotocol to 2025.0.0
+
+## [2026.8.300] - 2026-08-28
+
+### Added
+
+- Integrate the NX Tcl Remote Debugger; the separate `local-nx.nx-tcl-debug` extension is no longer needed
+- `nx-tcl` attach configurations and breakpoints in Tcl and DEF files
+- Stepping, call stack, scopes, variables, watches, evaluation, logpoints, hit conditions, and Tcl error stops
+- Breakpoints in `LIB_GE_command_buffer_edit_*` bodies, mapped back to their source and owning procedure
+
+## [2026.8.200] - 2026-08-19
+
+### Added
+
+- Configurable parameter-name inlay hints (`inlayHints.parameterNames`, `inlayHints.suppressWhenArgumentMatchesName`) for custom and built-in NX procedures, including variadic arguments
+- Unlimited inlay hint length for Tcl files, so later parameter names are not truncated
+
+### Changed
+
+- Cache semantic tokens, inlay hints, hover, completion, and variable indexes and debounce edits and diagnostics for faster responses
+
+## [2026.8.100] - 2026-08-19
+
+### Added
+
+- Workspace symbol index with Go to Definition, references, and rename
+- Signature help for custom Tcl procedures and built-in NX/MOM procedures
+- CDL event handler snippets and hover with generated handler and `mom_` parameter hints
+- Keep indexes in sync when Tcl files are changed, deleted, or renamed on disk
+
+## [2026.6.201] - 2026-06-22
+
+### Fixed
+
+- Preserve whitespace inside single-line braced expressions when formatting
+
+## [2026.6.200] - 2026-06-22
+
+### Fixed
+
+- Tcl formatting bug caused by the formatter options
+
+## [2026.6.100] - 2026-06-18
+
+### Changed
+
+- Folding ranges for Tcl are computed by the language server, avoiding duplicate regions
+- Language server restarts are serialized so only one server runs at a time
+- Pin the Python dependencies of the server and update the bundled libraries
+
+### Fixed
+
+- Several stability fixes
+
+## [2025.9.200] - 2025-09-01
+
+### Changed
+
+- Install server dependencies with uv instead of pip
+- Relicense to AGPL-3.0-or-later
+
+## [2025.9.101] - 2025-08-16
+
+### Added
+
+- Signature help
+- Variable checks and additional semantic tokens
+
+### Fixed
+
+- `incr` on variables that already exist and `foreach` loop variables
+
+## [2025.8.400] - 2025-08-15
+
+### Added
+
+- Outline for DEF and CDL files
+
+### Fixed
+
+- Duplicate `MOM_add_to_block_buffer` entry renamed to `MOM_add_to_line_buffer`
+
+## [2025.8.300] - 2025-08-12
+
+### Added
+
+- Go to Definition and document outline for Tcl
+- Variable index with positions
+- Procedure documentation in hover
+
+### Fixed
+
+- Formatter deleting line continuations (`\`)
+- Wrong semantic highlighting in several cases
+
+## [2025.8.202] - 2025-08-12
+
+### Fixed
+
+- Formatter deleting line continuations (`\`)
+
+## [2025.8.201] - 2025-08-11
+
+### Fixed
+
+- Highlighting errors
+
+## [2025.8.200] - 2025-08-09
+
+- Version change only
+
+## [2025.8.2] - 2025-08-09
+
+- Version change only
+
+## [2025.08.1] - 2025-08-09
+
+### Added
+
+- Load procedures from all workspace files and PSC-referenced scripts for completion
+- Extension icon
+
+## [0.4.14] - 2025-08-04
+
+### Added
+
+- `LIB_GE_command_buffer_edit_*` support in the parser
+
+### Fixed
+
+- Namespace calls in POCO code
+- Semantic highlighting of variables in arrays
+
+## [0.4.12] - 2025-08-03
+
+### Added
+
+- More semantic tokens and completion items
+
+## [0.4.10] - 2025-07-28
+
+### Added
+
+- Linter based on tclint
+
+### Changed
+
+- Use tclint as parser and formatter
+
+## [0.4.9] - 2025-07-22
+
+### Added
+
+- More completion items
+
+## [0.4.8] - 2025-07-21
+
+### Added
+
+- More NX functions and hover documentation
+
+## [0.4.7] - 2025-07-21
+
+### Added
+
+- Formatter settings
+
+### Fixed
+
+- Formatter fixes
+
+## [0.4.6] - 2025-07-21
+
+### Fixed
+
+- `@` in buffers when formatting
+
+## [0.4.5] - 2025-07-21
+
+### Fixed
+
+- Formatting of buffers
+
+## [0.4.4] - 2025-07-21
+
+### Fixed
+
+- Formatter fixes
+
+## [0.4.3] - 2025-07-21
+
+### Fixed
+
+- Formatting fixes
+
+## [0.4.2] - 2025-07-20
+
+### Added
+
+- Initial release with syntax highlighting, formatting, auto-completion (including `TYPE`), hover, and DEF file support

README.md

@@ -14,6 +14,7 @@ A comprehensive VS Code extension providing language support and remote debuggin
 - **Document Highlights** - Highlights all reads, writes, and calls of the symbol under the cursor
 - **Context-aware Completion** - Prioritizes local symbols and suggests variables, procedures, namespaces, paths, Tcl subcommands, valid argument values, and options based on cursor context
 - **PSC and TclOO Classes** - Indexes Tcl scripts referenced by PSC layers, including external folders. Classes from indexed files provide method completion, signature help, parameter hints, and class highlighting in other files. PSC script names may omit `.tcl`; relative folders resolve from the PSC directory, and environment-variable folders are supported. Missing scripts are reported in the output channel; encrypted libraries cannot supply static class metadata.
+- **DEF Block Templates and Addresses** - Reads the `.def` files listed under `<DefinedEvents>` in PSC layers and suggests their `BLOCK_TEMPLATE` and `ADDRESS` names, see [DEF block templates and addresses](#def-block-templates-and-addresses)
 - **Tcl Snippets** - Inserts placeholder-based structures for `if`, `foreach`, `proc`, `switch`, `try`, and `dict for`
 - **NX Tcl Remote Debugger** - Breakpoints, stepping, call stack, scopes, variables, watches, evaluation, logpoints, hit conditions, and Tcl error stops directly in a running NX Post process
 
@@ -48,6 +49,52 @@ TCL files default to unlimited inlay hint length so that VS Code does not
 truncate later parameter names on a line. An explicit user setting for
 `editor.inlayHints.maximumLength` still takes precedence.
 
+## DEF Block Templates and Addresses
+
+The language server resolves the `.def` files of every PSC layer's `<DefinedEvents>` section the
+same way as layer scripts (relative to the PSC, `SubFolder`, environment variables, missing `.def`
+extension) and collects all `BLOCK_TEMPLATE` and `ADDRESS` declarations. Changes to PSC or DEF files
+are picked up automatically.
+
+| Command | Suggestions |
+|---|---|
+| `MOM_do_template` | Block templates, then variables |
+| `MOM_ask_address_value` | Addresses, then variables |
+| `MOM_force`, `MOM_suppress` | 1st argument: `Always`, `Once`, `Off`, then variables; further arguments: addresses, then variables |
+
+Block templates, addresses, and `Always|Once|Off` are inserted in quotes (`"steady_rest"`); a quote
+that is already typed or auto-closed is replaced instead of doubled. Variables are inserted with a
+leading `$`. Typing `$` yourself still shows variables only.
+
+Two keywords list all loaded names anywhere in a Tcl file:
+
+- `BLOCK_LIST` - shows all block templates
+- `ADDR_LIST` - shows all addresses
+
+Select the keyword from the completion list (or type it completely) to open the list; text typed
+directly after the keyword, such as `ADDR_LISTSP`, narrows it. The keyword is replaced by the
+selected quoted name.
+
+### Navigation between Tcl and DEF files
+
+Block template and address names are linked to their declarations in the PSC `.def` files:
+
+- **Go to Definition** (F12) on `MOM_do_template "steady_rest"` or `MOM_force Once X` jumps to
+  `BLOCK_TEMPLATE steady_rest` or `ADDRESS X`. Inside a `.def` file, an address used in a block
+  template (`X[$mom_pos(0)]`) jumps to its `ADDRESS` declaration.
+- **Hover** shows the body of a block template, or the format (resolved to its `FORMAT`
+  definition), leader, trailer, min/max, and modality (`FORCE`) of an address.
+- **Find All References** (Shift+F12) lists the declaration, all Tcl calls, and all block templates
+  that use an address.
+- **Rename** (F2) changes the declaration and all usages in Tcl and `.def` files together. Only
+  names declared in a loaded `.def` file can be renamed.
+
+Recognized Tcl commands: `MOM_do_template`, `MOM_add_to_block_buffer`, `MOM_polar_motion`,
+`MOM_force_block`, `MOM_ask_address_value`, `MOM_add_to_address_buffer`, `MOM_enable_address`,
+`MOM_disable_address`, `MOM_force`, `MOM_suppress`, `MOM_incremental`, and
+`MOM_ask_definition_element`/`MOM_has_definition_element` with `ADDRESS` or `BLOCK`. Names built
+from variables (`MOM_do_template $name`) cannot be resolved statically.
+
 ## NX Tcl Remote Debugger
 
 ### Add a VS Code attach configuration
@@ -98,13 +145,15 @@ Simply open any supported file type and enjoy:
 - Syntax highlighting
 - Error detection and linting
 - Code completion
-- Code formatting (Format Document command)
+- Code formatting (Format Document command), including `uplevel` bodies and a space after `#` in comments
 - Hover information
 - Signature help while entering procedure arguments
 - Incoming and outgoing call hierarchy for custom procedures and MOM event handlers
 - Document-wide highlights for procedure and variable occurrences
 - Context-aware completion with local symbols ranked before workspace and built-in symbols, plus semantic arguments, local paths, Tcl subcommands, and options such as `string compare -nocase`
 - Placeholder-based snippets for common Tcl control structures and procedures
+- Block template and address suggestions from PSC DEF files, including `BLOCK_LIST` and `ADDR_LIST`
+- Go to Definition, hover, references, and rename for block templates and addresses across Tcl and DEF files
 - Remote NX Tcl debugging with breakpoints and full stepping
 
 ## Contributing

client/src/common/defProviders.ts

@@ -0,0 +1,81 @@
+import * as vscode from "vscode"
+import { LanguageClient, Range, State } from "vscode-languageclient/node"
+
+// .def files are not synchronized with the language server, so each request
+// carries the current text of the document.
+const DEF_SELECTOR: vscode.DocumentSelector = { scheme: "file", language: "def" }
+
+function params(document: vscode.TextDocument, position: vscode.Position, extra: object = {}) {
+    return {
+        textDocument: { uri: document.uri.toString() },
+        position: { line: position.line, character: position.character },
+        text: document.getText(),
+        ...extra
+    }
+}
+
+export function registerDefProviders(getClient: () => LanguageClient | undefined): vscode.Disposable[] {
+    const request = async <T>(
+        method: string,
+        document: vscode.TextDocument,
+        position: vscode.Position,
+        token: vscode.CancellationToken,
+        extra: object = {}
+    ): Promise<{ client: LanguageClient; result: T } | undefined> => {
+        const client = getClient()
+        if (!client || client.state !== State.Running) {
+            return undefined
+        }
+        const result = await client.sendRequest<T>(method, params(document, position, extra), token)
+        return result ? { client, result } : undefined
+    }
+
+    return [
+        vscode.languages.registerDefinitionProvider(DEF_SELECTOR, {
+            async provideDefinition(document, position, token) {
+                const response = await request<any>("nxPostSupport/def/definition", document, position, token)
+                return response && response.client.protocol2CodeConverter.asDefinitionResult(response.result, token)
+            }
+        }),
+        vscode.languages.registerHoverProvider(DEF_SELECTOR, {
+            async provideHover(document, position, token) {
+                const response = await request<any>("nxPostSupport/def/hover", document, position, token)
+                return response && response.client.protocol2CodeConverter.asHover(response.result)
+            }
+        }),
+        vscode.languages.registerReferenceProvider(DEF_SELECTOR, {
+            async provideReferences(document, position, context, token) {
+                const response = await request<any>("nxPostSupport/def/references", document, position, token, {
+                    includeDeclaration: context.includeDeclaration
+                })
+                return response && response.client.protocol2CodeConverter.asReferences(response.result, token)
+            }
+        }),
+        vscode.languages.registerRenameProvider(DEF_SELECTOR, {
+            async prepareRename(document, position, token) {
+                const response = await request<{ range: Range; placeholder: string }>(
+                    "nxPostSupport/def/prepareRename",
+                    document,
+                    position,
+                    token
+                )
+                if (!response) {
+                    throw new Error("Only declared block templates and addresses can be renamed.")
+                }
+                return {
+                    range: response.client.protocol2CodeConverter.asRange(response.result.range),
+                    placeholder: response.result.placeholder
+                }
+            },
+            async provideRenameEdits(document, position, newName, token) {
+                const response = await request<any>("nxPostSupport/def/rename", document, position, token, {
+                    newName
+                })
+                if (!response) {
+                    throw new Error(`"${newName}" is not a valid block template or address name.`)
+                }
+                return response.client.protocol2CodeConverter.asWorkspaceEdit(response.result, token)
+            }
+        })
+    ]
+}

client/src/common/server.ts

@@ -22,7 +22,12 @@ import {
 import { getLSClientTraceLevel, getProjectRoot } from "./utilities"
 import { isVirtualWorkspace } from "./vscodeapi"
 
-export type IInitOptions = { settings: ISettings[]; globalSettings: ISettings }
+export type IInitOptions = {
+    settings: ISettings[]
+    globalSettings: ISettings
+    // Folder for the server's persistent index cache; omitted without a workspace.
+    indexCachePath?: string
+}
 
 let _disposables: Disposable[] = []
 
@@ -86,7 +91,7 @@ async function createServer(
     }
 
     // Options to control the language client
-    const tclFileWatcher = workspace.createFileSystemWatcher("**/*.{tcl,psc}")
+    const tclFileWatcher = workspace.createFileSystemWatcher("**/*.{tcl,psc,def}")
     const clientOptions: LanguageClientOptions = {
         // Register the server for python documents
         documentSelector: isVirtualWorkspace()
@@ -114,7 +119,8 @@ export async function restartServer(
     serverId: string,
     serverName: string,
     outputChannel: LogOutputChannel,
-    lsClient?: LanguageClient
+    lsClient?: LanguageClient,
+    indexCachePath?: string
 ): Promise<LanguageClient | undefined> {
     if (lsClient) {
         traceInfo(`Server: Stop requested`)
@@ -132,7 +138,8 @@ export async function restartServer(
             outputChannel,
             {
                 settings: await getExtensionSettings(serverId, true),
-                globalSettings: await getGlobalSettings(serverId, false)
+                globalSettings: await getGlobalSettings(serverId, false),
+                indexCachePath
             }
         )
         traceInfo(`Server: Start requested.`)

client/src/extension.ts

@@ -16,6 +16,7 @@ import {
     defDocumentSymbolProvider,
     definitionCdlEventHandler
 } from "./common/handlers"
+import { registerDefProviders } from "./common/defProviders"
 import { registerLogger, traceError, traceLog, traceVerbose } from "./common/log/logging"
 import {
     checkVersion,
@@ -73,7 +74,13 @@ export async function activate(context: vscode.ExtensionContext) {
                 traceVerbose(
                     `Using interpreter from ${serverInfo.module}.interpreter: ${interpreter.join(" ")}`
                 )
-                client = await restartServer(serverId, serverName, outputChannel, client)
+                client = await restartServer(
+                    serverId,
+                    serverName,
+                    outputChannel,
+                    client,
+                    context.storageUri?.fsPath
+                )
             }
             return
         }
@@ -83,7 +90,13 @@ export async function activate(context: vscode.ExtensionContext) {
             traceVerbose(
                 `Using interpreter from Python extension: ${interpreterDetails.path.join(" ")}`
             )
-            client = await restartServer(serverId, serverName, outputChannel, client)
+            client = await restartServer(
+                serverId,
+                serverName,
+                outputChannel,
+                client,
+                context.storageUri?.fsPath
+            )
             return
         }
 
@@ -222,6 +235,7 @@ export async function activate(context: vscode.ExtensionContext) {
     )
 
     context.subscriptions.push(formatDefProvider)
+    context.subscriptions.push(...registerDefProviders(() => client))
 
     const cdlSymbolProvider = vscode.languages.registerDocumentSymbolProvider(
         { scheme: "file", language: "cdl" },

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "nx-post-support",
-  "version": "2026.8.201",
+  "version": "2026.9.501",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "nx-post-support",
-      "version": "2026.8.201",
+      "version": "2026.9.501",
       "devDependencies": {
         "@types/vscode": "^1.96.0",
         "@vscode/vsce": "^3.2.1",

package.json

@@ -2,7 +2,7 @@
   "name": "nx-post-support",
   "displayName": "NX Postprocessor Support",
   "description": "VS Code extension for NX CAM postprocessor development with language support and remote Tcl debugging for CDL, TCL, and DEF files",
-  "version": "2026.9.400",
+  "version": "2026.9.800",
   "publisher": "Christoph",
   "icon": "images/nx-1.png",
   "activationEvents": [

server/src/_debug_server.py

@@ -6,7 +6,7 @@ import os
 import pathlib
 import runpy
 import sys
-import time
+import threading
 
 
 def update_sys_path(path_to_add: str) -> None:
@@ -27,21 +27,35 @@ def _debug_endpoint() -> tuple[str, int]:
     return host, port
 
 
-def _connect_debugger(debugpy, host: str, port: int, timeout: float = 15.0) -> None:
-    deadline = time.monotonic() + timeout
-    last_error: OSError | None = None
-    while time.monotonic() < deadline:
+def _connect_debugger(debugpy, host: str, port: int, timeout: float = 30.0) -> None:
+    errors: list[BaseException] = []
+
+    def attach() -> None:
+        # debugpy.connect() cannot be retried: after a refused connection a second
+        # call terminates the process silently. Connect exactly once.
         try:
             debugpy.connect((host, port))
             debugpy.wait_for_client()
-            return
-        except (ConnectionRefusedError, OSError) as error:
-            last_error = error
-            time.sleep(0.25)
+        except BaseException as error:  # pylint: disable=broad-exception-caught
+            errors.append(error)
 
-    raise RuntimeError(
-        f"Could not connect debugpy to {host}:{port} within {timeout:.0f} seconds"
-    ) from last_error
+    # A stale debugpy adapter from an earlier debug session can still own the port.
+    # It accepts the connection but never attaches, so bound the wait.
+    waiter = threading.Thread(target=attach, daemon=True)
+    waiter.start()
+    waiter.join(timeout)
+    if waiter.is_alive():
+        raise RuntimeError(
+            f"Connected to {host}:{port}, but no VS Code debug session attached within "
+            f"{timeout:.0f} seconds. A stale debugpy adapter probably still owns the "
+            f"port; stop it (e.g. 'fuser -k {port}/tcp') and restart debugging."
+        )
+    if errors:
+        raise RuntimeError(
+            f"No debugpy listener on {host}:{port}. Start the launch configuration "
+            "'Python debug server (hidden)' (e.g. via a 'Debug Extension and Python' "
+            "compound) before the language server."
+        ) from errors[0]
 
 
 def main() -> None:
@@ -61,7 +75,12 @@ def main() -> None:
 
     host, port = _debug_endpoint()
     print(f"debugpy: waiting for VS Code at {host}:{port}", file=sys.stderr)
-    _connect_debugger(debugpy, host, port)
+    try:
+        _connect_debugger(debugpy, host, port)
+    except RuntimeError as error:
+        print(f"debugpy: {error}", file=sys.stderr, flush=True)
+        # debugpy's background threads can keep the interpreter alive; exit hard.
+        os._exit(1)
     print("debugpy: VS Code attached; starting language server", file=sys.stderr)
 
     server_path = os.fspath(pathlib.Path(__file__).parent / "lsp_server.py")

server/src/lsp_server.py

@@ -11,6 +11,7 @@ import pathlib
 import re
 import sys
 import threading
+import time
 from collections import ChainMap
 from functools import reduce
 from typing import Any, Optional
@@ -51,16 +52,26 @@ from tools.completion_items import (
     completion_context,
     ranked_completion_items,
 )
+from tools.def_navigation import (
+    all_def_target_locations,
+    def_declarations,
+    def_definition_locations,
+    def_hover_markdown,
+    def_rename_edits,
+    def_symbol_at,
+)
+from tools.def_symbols import parse_def_document
 from tools.folding_ranges import build_folding_ranges
+from tools.index_cache import IndexCache
 from tools.inlay_hint import (
     InlayHintGenerator,
     build_builtin_inlay_signatures,
 )
 from tools.navigation import (
+    DEF_SYMBOL_KINDS,
     SymbolIdentity,
     call_hierarchy_identity,
     call_hierarchy_items,
-    definition_identities,
     document_highlights,
     incoming_call_hierarchy,
     matching_occurrences,
@@ -77,19 +88,22 @@ from tools.semantic_tokens import (
 from tools.signature_help import build_signature_help
 from tools.tcloo_arguments import method_signature_help
 from tclint.lexer import TclSyntaxError
-from tools.tcloo_completion import parse_completion_source, tcloo_completions
+from tools.tcloo_completion import may_contain_classes, parse_completion_source, tcloo_completions
 from tools.tcloo_symbols import class_completion_items
 from tools.tcloo_navigation import tcloo_definition
 from tools.tcl_command_completion import (
     TCL_COMMAND_ITEMS,
     TCL_COMMAND_NAMES,
     DynamicCompletionKind,
+    line_prefix_at_position,
     path_completion_items,
     tcl_argument_completion,
 )
 
 WORKSPACE_SETTINGS = {}
 GLOBAL_SETTINGS = {}
+# Extension storage folder of the workspace; without it nothing is persisted.
+INDEX_CACHE_PATH: dict[str, str | None] = {}
 
 
 MAX_WORKERS = 5
@@ -176,6 +190,7 @@ def _index_tcl_file_from_disk(uri: str) -> None:
             document,
             cache_tree=False,
             require_file_exists=True,
+            from_disk=True,
         )
     except (OSError, UnicodeError) as error:
         log_warning(f"Could not re-index {path}: {error}")
@@ -215,21 +230,29 @@ def did_rename_files(params: lsp.RenameFilesParams) -> None:
 def did_change_watched_files(params: lsp.DidChangeWatchedFilesParams) -> None:
     """Keep indexes for closed Tcl files synchronized with disk changes."""
     for change in params.changes:
-        if pathlib.Path(uris.to_fs_path(change.uri)).suffix.lower() == ".psc":
+        suffix = pathlib.Path(uris.to_fs_path(change.uri)).suffix.lower()
+        if suffix == ".psc":
             _refresh_psc_index()
             continue
+        if suffix == ".def":
+            LSP_SERVER.refresh_def_symbols(_workspace_roots(), report=log_warning)
+            continue
         if change.type == lsp.FileChangeType.Deleted:
             LSP_SERVER.remove_file_state(change.uri)
         else:
             _index_tcl_file_from_disk(change.uri)
 
 
-def _refresh_psc_index():
+def _workspace_roots() -> list[pathlib.Path]:
     folders = LSP_SERVER.workspace.folders
     roots = [pathlib.Path(uris.to_fs_path(uri)) for uri in folders]
     if not roots and LSP_SERVER.workspace.root_path:
         roots = [pathlib.Path(LSP_SERVER.workspace.root_path)]
-    LSP_SERVER.refresh_psc_scripts(roots, report=log_warning)
+    return roots
+
+
+def _refresh_psc_index():
+    LSP_SERVER.refresh_psc_scripts(_workspace_roots(), report=log_warning)
 
 
 @LSP_SERVER.feature(
@@ -267,10 +290,78 @@ def document_diagnostic(params: lsp.DocumentDiagnosticParams):
     lsp.CompletionOptions(trigger_characters=["$", " ", "-", "(", ","]),
 )
 def on_completion(params: lsp.CompletionParams) -> lsp.CompletionList:
+    result = _on_completion(params)
+    doc = LSP_SERVER.workspace.get_text_document(params.text_document.uri)
+    symbol_list = _symbol_list_completion(LSP_SERVER.get_lines(doc), params.position)
+    if symbol_list is not None and symbol_list.is_incomplete:
+        # Re-request while typing so the full list appears at BLOCK_LIST/ADDR_LIST.
+        result.items = [*symbol_list.items, *result.items]
+        result.is_incomplete = True
+    return result
+
+
+# Keywords that expand to all loaded .def names: keyword -> (items, description).
+SYMBOL_LIST_KEYWORDS = {
+    "BLOCK_LIST": (lambda: LSP_SERVER.block_template_items(), "block templates"),
+    "ADDR_LIST": (lambda: LSP_SERVER.address_items(), "addresses"),
+}
+DEF_NAME_RE = re.compile(r"[A-Za-z_][A-Za-z0-9_]*")
+_WORD_BEFORE_CURSOR_RE = re.compile(r"(?<![$\w])[A-Za-z_]+$")
+
+
+def _symbol_list_completion(source_lines, position: lsp.Position) -> lsp.CompletionList | None:
+    """Complete BLOCK_LIST/ADDR_LIST to all loaded block templates/addresses.
+
+    While the typed word is a prefix of a keyword, an incomplete list with the
+    keyword itself is returned. Once the keyword is typed, the complete list of
+    quoted names replaces it.
+    """
+    line_prefix = line_prefix_at_position(source_lines, position)
+    match = _WORD_BEFORE_CURSOR_RE.search(line_prefix or "")
+    if match is None:
+        return None
+    word = match.group()
+    for keyword, (symbol_items, _) in SYMBOL_LIST_KEYWORDS.items():
+        if not word.startswith(keyword):
+            continue
+        items = []
+        ranked = ranked_completion_items(((0, item) for item in symbol_items()), CompletionContext.GENERAL)
+        for item in ranked:
+            item = _quoted_item(item, source_lines, position, word)
+            # Keep every name visible for the typed keyword; text after it narrows.
+            item.filter_text = f"{keyword}{item.label}"
+            items.append(item)
+        return lsp.CompletionList(is_incomplete=False, items=items)
+
+    keywords = [
+        lsp.CompletionItem(
+            label=keyword,
+            kind=lsp.CompletionItemKind.Snippet,
+            detail=f"Show all loaded {description}",
+            insert_text=keyword,
+            sort_text=f"000:{keyword.casefold()}",
+            command=lsp.Command(title=f"Show {description}", command="editor.action.triggerSuggest"),
+        )
+        for keyword, (_, description) in SYMBOL_LIST_KEYWORDS.items()
+        if keyword.startswith(word)
+    ]
+    if keywords:
+        return lsp.CompletionList(is_incomplete=True, items=keywords)
+    return None
+
+
+def _on_completion(params: lsp.CompletionParams) -> lsp.CompletionList:
     doc = LSP_SERVER.workspace.get_text_document(params.text_document.uri)
     position = params.position
     source_lines = LSP_SERVER.get_lines(doc)
-    oo_items = tcloo_completions(source_lines, position, LSP_SERVER.class_snapshot(doc.path))
+
+    def current_tree():
+        try:
+            return LSP_SERVER.get_tree(doc)
+        except TclSyntaxError:
+            return None
+
+    oo_items = tcloo_completions(source_lines, position, LSP_SERVER.class_snapshot(doc.path), current_tree)
     if oo_items is not None:
         return lsp.CompletionList(is_incomplete=False, items=oo_items)
     array_items = array_element_completions(
@@ -283,6 +374,10 @@ def on_completion(params: lsp.CompletionParams) -> lsp.CompletionList:
         return lsp.CompletionList(is_incomplete=False, items=array_items)
     context = completion_context(source_lines, position)
 
+    symbol_list = _symbol_list_completion(source_lines, position)
+    if symbol_list is not None and symbol_list.is_incomplete is False:
+        return symbol_list
+
     # Variable completion wins inside command arguments. Otherwise prefer the
     # narrow command grammar when the cursor is at a known subcommand/option.
     argument_completion = None
@@ -382,6 +477,30 @@ def on_completion(params: lsp.CompletionParams) -> lsp.CompletionList:
             items = [*ranked_completion_items(static_candidates, CompletionContext.GENERAL), *items]
             return lsp.CompletionList(is_incomplete=False, items=items)
 
+        def_symbol_items = {
+            DynamicCompletionKind.BLOCK_TEMPLATE: LSP_SERVER.block_template_items,
+            DynamicCompletionKind.ADDRESS: LSP_SERVER.address_items,
+            DynamicCompletionKind.VALUE: list,
+        }.get(argument_completion.dynamic_kind)
+        if def_symbol_items is not None:
+            # MOM_do_template, MOM_force, ... take a .def name, a fixed value (e.g.
+            # Always|Once|Off) or a variable holding one.
+            def_symbols = [*static_candidates, *((0, item) for item in def_symbol_items())]
+            variable_candidates = list(candidates)
+            variable_candidates.extend((300, item) for item in standard_items.nx_variables)
+            variables = []
+            for item in ranked_completion_items(variable_candidates, CompletionContext.VARIABLE):
+                # Without a typed "$" the variable must be substituted.
+                item.insert_text = f"${item.label}"
+                item.filter_text = item.label
+                item.text_edit = None
+                variables.append(item)
+            quoted = [
+                _quoted_item(item, source_lines, position, argument_completion.active_prefix)
+                for item in ranked_completion_items(def_symbols, CompletionContext.GENERAL)
+            ]
+            return lsp.CompletionList(is_incomplete=False, items=[*quoted, *variables])
+
         if argument_completion.dynamic_kind == DynamicCompletionKind.PROCEDURE:
             procedure_kinds = {
                 lsp.CompletionItemKind.Constructor,
@@ -425,6 +544,35 @@ def on_completion(params: lsp.CompletionParams) -> lsp.CompletionList:
     return lsp.CompletionList(is_incomplete=False, items=items)
 
 
+def _quoted_item(
+    item: lsp.CompletionItem,
+    source_lines,
+    position: lsp.Position,
+    active_prefix: str,
+) -> lsp.CompletionItem:
+    """Insert ``item`` as a quoted word, replacing quotes the user already typed."""
+    line = source_lines[position.line] if position.line < len(source_lines) else ""
+    utf16 = line.encode("utf-16-le")
+    start = position.character - len(active_prefix.encode("utf-16-le")) // 2
+    end = position.character
+    opened = start > 0 and utf16[(start - 1) * 2 : start * 2].decode("utf-16-le") == '"'
+    if opened:
+        start -= 1
+        # Also replace a closing quote the editor inserted automatically.
+        if utf16[end * 2 : (end + 1) * 2].decode("utf-16-le") == '"':
+            end += 1
+    item.text_edit = lsp.TextEdit(
+        range=lsp.Range(
+            start=lsp.Position(line=position.line, character=start),
+            end=lsp.Position(line=position.line, character=end),
+        ),
+        new_text=f'"{item.label}"',
+    )
+    item.insert_text = None
+    item.filter_text = f'"{item.label}' if opened else item.label
+    return item
+
+
 @LSP_SERVER.feature(
     lsp.TEXT_DOCUMENT_SIGNATURE_HELP,
     lsp.SignatureHelpOptions(
@@ -434,15 +582,15 @@ def on_completion(params: lsp.CompletionParams) -> lsp.CompletionList:
 )
 def signature_help(params: lsp.SignatureHelpParams) -> lsp.SignatureHelp | None:
     document = LSP_SERVER.workspace.get_text_document(params.text_document.uri)
-    method_help = method_signature_help(document.source, params.position, LSP_SERVER.class_snapshot(document.path))
-    if method_help is not None:
-        return method_help
     try:
         tree = LSP_SERVER.get_tree(document)
     except TclSyntaxError:
         tree = parse_completion_source(document.source)
         if tree is None:
             return None
+    method_help = method_signature_help(document.source, params.position, LSP_SERVER.class_snapshot(document.path), tree)
+    if method_help is not None:
+        return method_help
 
     custom_signatures, custom_docs = LSP_SERVER.proc_metadata_snapshot(document.path)
 
@@ -522,8 +670,9 @@ def semantic_tokens(params: lsp.SemanticTokensParams):
     # Reuse cached AST
     tree = LSP_SERVER.get_tree(document)
     classes = LSP_SERVER.class_snapshot(document.path)
-    hl.highlight_classes(tree, classes)
-    hl.highlight_methods(tree, document.source, document.uri, classes)
+    if may_contain_classes(document.source, classes):
+        hl.highlight_classes(tree, classes)
+        hl.highlight_methods(tree, document.source, document.uri, classes)
     tree.accept(hl, recurse=True)
 
     tokens = hl.tokens()
@@ -571,6 +720,10 @@ def hover(params: lsp.HoverParams) -> lsp.Hover:
     else:
         return None
 
+    def_hover = _tcl_def_hover(document_uri, pos, token)
+    if def_hover is not None:
+        return def_hover
+
     # 1) If token is a known MOM proc/variable, return built-in hover
     match = BUILTIN_HOVER_ITEMS.get(token)
     if match and match.get("kind") == "function":
@@ -610,6 +763,22 @@ def hover(params: lsp.HoverParams) -> lsp.Hover:
     return None
 
 
+def _def_target(identity: SymbolIdentity) -> tuple[str, str] | None:
+    return (identity.kind, identity.name) if identity.kind in DEF_SYMBOL_KINDS else None
+
+
+def _tcl_def_hover(uri: str, position: lsp.Position, token: str) -> lsp.Hover | None:
+    documents = LSP_SERVER.def_documents_snapshot()
+    if not any(token in document.names(kind) for document in documents.values() for kind in DEF_SYMBOL_KINDS):
+        return None
+    context = _navigation_context(uri, position)
+    target = context and _def_target(context[3])
+    markdown = target and def_hover_markdown(documents, target)
+    if not markdown:
+        return None
+    return lsp.Hover(lsp.MarkupContent(kind=lsp.MarkupKind.Markdown, value=markdown), range=context[2].range)
+
+
 @LSP_SERVER.feature(lsp.TEXT_DOCUMENT_DEFINITION)
 def goto_definition(params: lsp.DefinitionParams):
     """Resolve TclOO declarations, then indexed proc and variable definitions."""
@@ -619,8 +788,12 @@ def goto_definition(params: lsp.DefinitionParams):
         workspace = None
     if workspace is not None:
         document = workspace.get_text_document(params.text_document.uri)
+        try:
+            tree = LSP_SERVER.get_tree(document)
+        except TclSyntaxError:
+            tree = None  # tcloo_definition repairs open delimiters itself.
         target = tcloo_definition(document.source, document.uri, params.position,
-                                  LSP_SERVER.class_snapshot(document.path))
+                                  LSP_SERVER.class_snapshot(document.path), tree)
         if target is not None:
             return [target]
     context = _navigation_context(params.text_document.uri, params.position)
@@ -628,23 +801,25 @@ def goto_definition(params: lsp.DefinitionParams):
         return None
 
     indexes, definitions, _, identity = context
+    target = _def_target(identity)
+    if target is not None:
+        return _sorted_locations(def_definition_locations(LSP_SERVER.def_documents_snapshot(), target)) or None
     locations = [lsp.Location(uri=index.uri, range=occurrence.range) for index, occurrence in matching_occurrences(identity, indexes, definitions) if occurrence.is_definition]
     return _sorted_locations(locations) or None
 
 
 def _navigation_context(uri: str, position: lsp.Position):
-    indexes = LSP_SERVER.navigation_snapshot()
+    indexes, definitions = LSP_SERVER.navigation_state()
     filepath = str(pathlib.Path(uris.to_fs_path(uri)))
     index = indexes.get(filepath)
     if index is None or LSP_SERVER.index_update_pending(filepath):
         document = LSP_SERVER.workspace.get_text_document(uri)
         LSP_SERVER.update_poco_completion_for_file(document)
-        indexes = LSP_SERVER.navigation_snapshot()
+        indexes, definitions = LSP_SERVER.navigation_state()
         index = indexes.get(filepath)
     if index is None:
         return None
 
-    definitions = definition_identities(indexes)
     result = symbol_at_position(index, position, definitions)
     if result is None:
         return None
@@ -670,6 +845,11 @@ def references(params: lsp.ReferenceParams) -> list[lsp.Location]:
         return []
 
     indexes, definitions, _, identity = context
+    target = _def_target(identity)
+    if target is not None:
+        return all_def_target_locations(
+            LSP_SERVER.def_documents_snapshot(), indexes, target, params.context.include_declaration
+        )
     locations = [
         lsp.Location(uri=index.uri, range=occurrence.range)
         for index, occurrence in matching_occurrences(identity, indexes, definitions)
@@ -717,7 +897,11 @@ def prepare_rename(params: lsp.PrepareRenameParams):
         return None
 
     indexes, definitions, occurrence, identity = context
-    if not _is_renamable(identity, indexes, definitions):
+    target = _def_target(identity)
+    if target is not None:
+        if not def_declarations(LSP_SERVER.def_documents_snapshot(), target):
+            return None
+    elif not _is_renamable(identity, indexes, definitions):
         return None
     return lsp.PrepareRenamePlaceholder(range=occurrence.range, placeholder=occurrence.placeholder)
 
@@ -727,7 +911,7 @@ def prepare_rename(params: lsp.PrepareRenameParams):
     lsp.RenameOptions(prepare_provider=True),
 )
 def rename(params: lsp.RenameParams) -> lsp.WorkspaceEdit | None:
-    if not re.fullmatch(r"[A-Za-z_][A-Za-z0-9_]*", params.new_name):
+    if not DEF_NAME_RE.fullmatch(params.new_name):
         return None
 
     context = _navigation_context(params.text_document.uri, params.position)
@@ -735,6 +919,9 @@ def rename(params: lsp.RenameParams) -> lsp.WorkspaceEdit | None:
         return None
 
     indexes, definitions, _, identity = context
+    target = _def_target(identity)
+    if target is not None:
+        return def_rename_edits(LSP_SERVER.def_documents_snapshot(), indexes, target, params.new_name)
     if not _is_renamable(identity, indexes, definitions):
         return None
 
@@ -764,6 +951,83 @@ def rename(params: lsp.RenameParams) -> lsp.WorkspaceEdit | None:
     return lsp.WorkspaceEdit(changes=changes)
 
 
+# .def files are not synchronized with the server; the client sends their
+# current text with each request.
+DEF_REQUEST_DEFINITION = "nxPostSupport/def/definition"
+DEF_REQUEST_HOVER = "nxPostSupport/def/hover"
+DEF_REQUEST_REFERENCES = "nxPostSupport/def/references"
+DEF_REQUEST_PREPARE_RENAME = "nxPostSupport/def/prepareRename"
+DEF_REQUEST_RENAME = "nxPostSupport/def/rename"
+
+
+def _def_request_context(params):
+    uri = params.textDocument.uri
+    position = lsp.Position(line=params.position.line, character=params.position.character)
+    path = uris.to_fs_path(uri)
+    documents = LSP_SERVER.def_documents_snapshot(path, params.text)
+    symbol = def_symbol_at(parse_def_document(params.text), position)
+    if symbol is None:
+        return None
+    target, range_, _ = symbol
+    current = next(key for key in documents if LSP_SERVER.paths_equal(key, path))
+    return documents, {current: uri}, target, range_
+
+
+@LSP_SERVER.feature(DEF_REQUEST_DEFINITION)
+def def_definition(params) -> list[lsp.Location] | None:
+    context = _def_request_context(params)
+    if context is None:
+        return None
+    documents, def_uris, target, _ = context
+    return _sorted_locations(def_definition_locations(documents, target, def_uris)) or None
+
+
+@LSP_SERVER.feature(DEF_REQUEST_HOVER)
+def def_hover(params) -> lsp.Hover | None:
+    context = _def_request_context(params)
+    if context is None:
+        return None
+    documents, _, target, range_ = context
+    markdown = def_hover_markdown(documents, target)
+    if markdown is None:
+        return None
+    return lsp.Hover(lsp.MarkupContent(kind=lsp.MarkupKind.Markdown, value=markdown), range=range_)
+
+
+@LSP_SERVER.feature(DEF_REQUEST_REFERENCES)
+def def_references(params) -> list[lsp.Location]:
+    context = _def_request_context(params)
+    if context is None:
+        return []
+    documents, def_uris, target, _ = context
+    include_declaration = bool(getattr(params, "includeDeclaration", True))
+    indexes, _ = LSP_SERVER.navigation_state()
+    return all_def_target_locations(documents, indexes, target, include_declaration, def_uris)
+
+
+@LSP_SERVER.feature(DEF_REQUEST_PREPARE_RENAME)
+def def_prepare_rename(params):
+    context = _def_request_context(params)
+    if context is None:
+        return None
+    documents, _, target, range_ = context
+    if not def_declarations(documents, target):
+        return None
+    return lsp.PrepareRenamePlaceholder(range=range_, placeholder=target[1])
+
+
+@LSP_SERVER.feature(DEF_REQUEST_RENAME)
+def def_rename(params) -> lsp.WorkspaceEdit | None:
+    if not DEF_NAME_RE.fullmatch(params.newName):
+        return None
+    context = _def_request_context(params)
+    if context is None:
+        return None
+    documents, def_uris, target, _ = context
+    indexes, _ = LSP_SERVER.navigation_state()
+    return def_rename_edits(documents, indexes, target, params.newName, def_uris)
+
+
 @LSP_SERVER.feature(lsp.WORKSPACE_SYMBOL)
 def workspace_symbol(params: lsp.WorkspaceSymbolParams):
     return workspace_symbols(LSP_SERVER.navigation_snapshot(), params.query)
@@ -786,12 +1050,8 @@ def incoming_calls(params: lsp.CallHierarchyIncomingCallsParams):
     if identity is None:
         return []
 
-    indexes = LSP_SERVER.navigation_snapshot()
-    return incoming_call_hierarchy(
-        identity,
-        indexes,
-        definition_identities(indexes),
-    )
+    indexes, definitions = LSP_SERVER.navigation_state()
+    return incoming_call_hierarchy(identity, indexes, definitions)
 
 
 @LSP_SERVER.feature(lsp.CALL_HIERARCHY_OUTGOING_CALLS)
@@ -800,12 +1060,8 @@ def outgoing_calls(params: lsp.CallHierarchyOutgoingCallsParams):
     if identity is None:
         return []
 
-    indexes = LSP_SERVER.navigation_snapshot()
-    return outgoing_call_hierarchy(
-        identity,
-        indexes,
-        definition_identities(indexes),
-    )
+    indexes, definitions = LSP_SERVER.navigation_state()
+    return outgoing_call_hierarchy(identity, indexes, definitions)
 
 
 # **********************************************************
@@ -859,6 +1115,7 @@ def initialize(params: lsp.InitializeParams) -> lsp.InitializeResult:
     log_to_output(f"sys.path used to run Server:\r\n   {paths}")
 
     GLOBAL_SETTINGS.update(**params.initialization_options.get("globalSettings", {}))
+    INDEX_CACHE_PATH["path"] = params.initialization_options.get("indexCachePath")
 
     settings = params.initialization_options["settings"]
     _update_workspace_settings(settings)
@@ -897,6 +1154,8 @@ def initialized(_params: lsp.InitializedParams):
                 log_to_output("Background indexing skipped: no workspace folder is open.")
                 return
             log_to_output("Background indexing started...")
+            started = time.perf_counter()
+            LSP_SERVER.index_cache = IndexCache.load(INDEX_CACHE_PATH.get("path"))
             root_path = pathlib.Path(root)
             skipped_directories = {
                 ".git",
@@ -914,11 +1173,13 @@ def initialized(_params: lsp.InitializedParams):
                         document,
                         cache_tree=False,
                         require_file_exists=True,
+                        from_disk=True,
                     )
                 except Exception as error:
                     log_to_output(f"Fehler beim Parsen von {filepath}: {error}")
             _refresh_psc_index()
-            log_to_output("Background indexing completed.")
+            LSP_SERVER.index_cache.save()
+            log_to_output(f"Background indexing completed in {time.perf_counter() - started:.1f}s.")
         except Exception as e:
             log_to_output(f"Background indexing failed: {e}")
 

server/src/lsp_tclserver.py

@@ -3,6 +3,7 @@ import os
 import pathlib
 import threading
 import xml.etree.ElementTree as ET
+from dataclasses import dataclass
 from typing import List, Optional, Tuple
 
 import lsprotocol.types as lsp
@@ -13,14 +14,21 @@ from pygls.workspace.text_document import TextDocument
 from tclint.format import FormatterOpts
 from tclint.lexer import TclSyntaxError
 from tclint.violations import Violation
-from tools import checks, parser
+from tools import checks, incremental_parse, parser
 from tools.completion_items import CompletionCollector
 from tools.tcloo_symbols import class_completion_items
 from tools.tcloo_completion import indexed_classes
-from tools.file_sourcing import get_all_psc_files, psc_script_files
+from tools.def_symbols import ADDRESS, BLOCK_TEMPLATE, DefDocument, parse_def_document, read_def_source
+from tools.file_sourcing import get_all_psc_files, psc_defined_event_files, psc_script_files
 from tools.formatter import NxFormatter as Formatter
+from tools.index_cache import FileStat, IndexCache, file_stat
 from tools.inlay_hint import InlayHintSignature, build_custom_inlay_signatures
-from tools.navigation import FileSymbolIndex, build_file_symbol_index
+from tools.navigation import (
+    FileSymbolIndex,
+    SymbolIdentity,
+    build_file_symbol_index,
+    definition_identities,
+)
 from tools.proc_docs import build_proc_docs
 from tools.variable_index import ProcRange, build_variable_index
 
@@ -28,6 +36,18 @@ DIAGNOSTIC_SOURCE = "nx-post-support"
 LOGGER = logging.getLogger(__name__)
 
 
+@dataclass(frozen=True)
+class _FileIndex:
+    """Everything indexed for one file; also the persistent cache entry."""
+
+    completion_items: list[lsp.CompletionItem]
+    proc_signatures: dict[str, list[str]]
+    proc_docs: dict[str, str]
+    classes: dict
+    navigation_index: FileSymbolIndex
+    variable_index: tuple[set[str], dict[str, set[str]], list[ProcRange]]
+
+
 class TclLanguageServer(LanguageServer):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
@@ -42,6 +62,8 @@ class TclLanguageServer(LanguageServer):
         self.psc_script_paths: list[str] = []
         self._psc_files: dict[str, list[pathlib.Path]] = {}
         self._psc_lock = threading.RLock()
+        # .def path -> parsed declarations, in PSC DefinedEvents order.
+        self.def_documents: dict[str, DefDocument] = {}
         self.navigation_indexes: dict[str, FileSymbolIndex] = {}
         self.variable_indexes: dict[
             str,
@@ -54,6 +76,11 @@ class TclLanguageServer(LanguageServer):
         self._ast_cache = {}
         self._line_cache: dict[tuple[str, int | None], tuple[str, ...]] = {}
         self._parser_lock = threading.RLock()
+        self._thread_parsers = threading.local()
+        # uri -> (normalized source, tree, violations) of the last successful
+        # parse; survives version changes so edits can be reparsed partially.
+        self._last_parse: dict[str, tuple[str, object, list]] = {}
+        self.index_cache = IndexCache()
         self._index_lock = threading.RLock()
         self._index_tokens: dict[str, int] = {}
         self._index_versions: dict[str, int | None] = {}
@@ -67,6 +94,9 @@ class TclLanguageServer(LanguageServer):
             -1,
             frozenset(),
         )
+        self._definition_identities_cache: tuple[
+            int, frozenset[SymbolIdentity]
+        ] = (-1, frozenset())
         self._proc_metadata_cache: dict[
             str, tuple[int, dict[str, list[str]], dict[str, str]]
         ] = {}
@@ -78,16 +108,44 @@ class TclLanguageServer(LanguageServer):
         self._analysis_tokens: dict[str, int] = {}
         self._next_analysis_token = 0
 
-    def _parse_source(self, source: str):
+    def _parse_source(self, source: str, pos=None):
         self.parser.violations = []
-        tree = self.parser.parse(source)
+        tree = self.parser.parse(source, pos=pos)
         return tree, list(self.parser.violations)
 
+    def _parse_document(self, document: TextDocument):
+        """Parse a document version, reusing unchanged parts of the last one.
+
+        Callers hold the parser lock.
+        """
+        source = incremental_parse.normalize_newlines(document.source)
+        previous = self._last_parse.get(document.uri)
+        result = None
+        if previous is not None:
+            try:
+                result = incremental_parse.reparse(
+                    *previous, source, self._parse_source
+                )
+            except TclSyntaxError:
+                # E.g. a quote opened in the edit closes further down.
+                result = None
+        if result is None:
+            result = self._parse_source(source)
+        self._last_parse[document.uri] = (source, *result)
+        return result
+
     def parse_source(self, source: str):
-        """Parse without retaining an AST, serialized around the shared parser."""
-        with self._parser_lock:
-            tree, _ = self._parse_source(source)
-            return tree
+        """Parse without retaining an AST, on a parser owned by this thread.
+
+        Background indexing must not hold the shared parser lock for whole
+        files while request handlers wait for their document's tree.
+        """
+        local_parser = getattr(self._thread_parsers, "parser", None)
+        if local_parser is None:
+            # Plugin commands live in tclint's shared registry, see __init__.
+            local_parser = self._thread_parsers.parser = parser.CustomParser()
+        local_parser.violations = []
+        return local_parser.parse(source)
 
     def get_tree(self, document: TextDocument):
         key = (document.uri, document.version)
@@ -95,7 +153,7 @@ class TclLanguageServer(LanguageServer):
             cached = self._ast_cache.get(key)
             if cached is not None:
                 return cached[0]
-            tree, violations = self._parse_source(document.source)
+            tree, violations = self._parse_document(document)
             self._ast_cache[key] = (tree, violations)
             return tree
 
@@ -105,7 +163,7 @@ class TclLanguageServer(LanguageServer):
             cached = self._ast_cache.get(key)
             if cached is not None:
                 return cached
-            tree, violations = self._parse_source(document.source)
+            tree, violations = self._parse_document(document)
             self._ast_cache[key] = (tree, violations)
             return tree, violations
 
@@ -154,6 +212,7 @@ class TclLanguageServer(LanguageServer):
         self._index_generation += 1
         self._workspace_completion_cache = (-1, ())
         self._custom_function_names_cache = (-1, frozenset())
+        self._definition_identities_cache = (-1, frozenset())
         self._proc_metadata_cache.clear()
         self._custom_inlay_cache.clear()
 
@@ -196,8 +255,55 @@ class TclLanguageServer(LanguageServer):
                     classes.update(indexes.get(self._normalized_path(path), {}))
             return classes
 
+    def refresh_def_symbols(self, roots, report=LOGGER.warning):
+        """Read the block templates and addresses of all .def files listed as PSC DefinedEvents."""
+        documents: dict[str, DefDocument] = {}
+        for root in roots:
+            for psc in get_all_psc_files(root):
+                try:
+                    def_files = psc_defined_event_files(psc)
+                except (OSError, ET.ParseError) as error:
+                    report(f"Could not read PSC {psc}: {error}")
+                    continue
+                for def_file in def_files:
+                    if str(def_file) in documents:
+                        continue
+                    try:
+                        documents[str(def_file)] = parse_def_document(read_def_source(def_file))
+                    except OSError as error:
+                        report(f"Could not read DEF file {def_file}: {error}")
+        with self._index_lock:
+            self.def_documents = documents
+
+    def def_documents_snapshot(self, current_path=None, current_source: str | None = None) -> dict[str, DefDocument]:
+        """Return the PSC .def documents; ``current_source`` replaces the file being edited."""
+        with self._index_lock:
+            documents = dict(self.def_documents)
+        if current_path is not None and current_source is not None:
+            key = next((path for path in documents if self.paths_equal(path, current_path)), os.fspath(current_path))
+            documents[key] = parse_def_document(current_source)
+        return documents
+
+    def _def_symbol_items(self, kind: str, item_kind, description: str) -> list[lsp.CompletionItem]:
+        return [
+            lsp.CompletionItem(
+                label=name,
+                kind=item_kind,
+                detail=f"{description} ({pathlib.Path(path).name})",
+            )
+            for path, document in self.def_documents_snapshot().items()
+            for name in document.names(kind)
+        ]
+
+    def block_template_items(self) -> list[lsp.CompletionItem]:
+        return self._def_symbol_items(BLOCK_TEMPLATE, lsp.CompletionItemKind.Struct, "Block template")
+
+    def address_items(self) -> list[lsp.CompletionItem]:
+        return self._def_symbol_items(ADDRESS, lsp.CompletionItemKind.Field, "Address")
+
     def refresh_psc_scripts(self, roots, report=LOGGER.warning):
         """Index PSC dependencies through the same pipeline as workspace procs."""
+        self.refresh_def_symbols(roots, report=report)
         with self._psc_lock:
             discovered = {}
             for root in roots:
@@ -233,7 +339,9 @@ class TclLanguageServer(LanguageServer):
                     report(f"PSC script not found: {path}")
                     continue
                 try:
+                    source_stat = None
                     if document is None:
+                        source_stat = file_stat(path_string)
                         data = path.read_bytes()
                         try:
                             source = data.decode("utf-8-sig")
@@ -241,7 +349,7 @@ class TclLanguageServer(LanguageServer):
                             # Older Windows NX layers use the ANSI code page.
                             source = data.decode("cp1252")
                         document = TextDocument(uri=uri, source=source, language_id="tcl")
-                    if not self.update_poco_completion_for_file(document, cache_tree=False):
+                    if not self.update_poco_completion_for_file(document, cache_tree=False, source_stat=source_stat):
                         report(f"Could not index PSC script: {path}")
                 except (OSError, UnicodeError) as error:
                     report(f"Could not read PSC script {path}: {error}")
@@ -505,6 +613,22 @@ class TclLanguageServer(LanguageServer):
         with self._index_lock:
             return dict(self.navigation_indexes)
 
+    def navigation_state(
+        self,
+    ) -> tuple[dict[str, FileSymbolIndex], frozenset[SymbolIdentity]]:
+        """Return indexes plus their definitions, cached by index generation."""
+        with self._index_lock:
+            generation, definitions = self._definition_identities_cache
+            if generation != self._index_generation:
+                definitions = frozenset(
+                    definition_identities(self.navigation_indexes)
+                )
+                self._definition_identities_cache = (
+                    self._index_generation,
+                    definitions,
+                )
+            return dict(self.navigation_indexes), definitions
+
     def _begin_index_update(self, filepath: str, version: int | None) -> int | None:
         with self._index_lock:
             indexed_version = self._index_versions.get(filepath)
@@ -599,6 +723,33 @@ class TclLanguageServer(LanguageServer):
                 if self._is_same_or_child(cached_path, target):
                     self._ast_cache.pop(key, None)
                     self._line_cache.pop(key, None)
+            for uri in list(self._last_parse):
+                try:
+                    parsed_path = pathlib.Path(uris.to_fs_path(uri))
+                except (TypeError, ValueError):
+                    continue
+                if self._is_same_or_child(parsed_path, target):
+                    del self._last_parse[uri]
+
+    def _build_file_index(
+        self, document: TextDocument, filepath: str, cache_tree: bool
+    ) -> "_FileIndex":
+        tree = (
+            self.get_tree(document)
+            if cache_tree
+            else self.parse_source(document.source)
+        )
+        collector = CompletionCollector()
+        tree.accept(collector, recurse=True)
+        collector.custom_functions.extend(class_completion_items(tree))
+        return _FileIndex(
+            completion_items=list(collector.custom_functions),
+            proc_signatures=dict(collector.proc_signatures),
+            proc_docs=build_proc_docs(tree, document.source),
+            classes=indexed_classes(tree, document.uri, document.source),
+            navigation_index=build_file_symbol_index(filepath, document.uri, tree),
+            variable_index=build_variable_index(document.source, tree),
+        )
 
     def update_poco_completion_for_file(
         self,
@@ -606,32 +757,32 @@ class TclLanguageServer(LanguageServer):
         *,
         cache_tree: bool = True,
         require_file_exists: bool = False,
+        from_disk: bool = False,
+        source_stat: FileStat | None = None,
     ):
-        """Update poco_completion for a specific file when it changes"""
+        """Update poco_completion for a specific file when it changes.
+
+        `from_disk` marks documents that read their source from disk lazily;
+        `source_stat` is the file's stat taken before a caller read it. Such
+        results are served from and stored in the persistent index cache.
+        """
         filepath = str(pathlib.Path(uris.to_fs_path(document.uri)))
         token = self._begin_index_update(filepath, document.version)
         if token is None:
             return False
 
-        collector = CompletionCollector()
-        try:
-            tree = (
-                self.get_tree(document)
-                if cache_tree
-                else self.parse_source(document.source)
-            )
-            tree.accept(collector, recurse=True)
-            collector.custom_functions.extend(class_completion_items(tree))
-            classes = indexed_classes(tree, document.uri, document.source)
-            docs = build_proc_docs(tree, document.source)
-            navigation_index = build_file_symbol_index(
-                filepath, document.uri, tree
-            )
-            variable_index = build_variable_index(document.source, tree)
-        except Exception as e:
-            LOGGER.debug("Error parsing %s: %s", filepath, e)
-            self._discard_index_update(filepath, token)
-            return False
+        stat = source_stat or (file_stat(filepath) if from_disk else None)
+        index = self.index_cache.get(filepath, stat) if stat is not None else None
+        if index is None:
+            try:
+                index = self._build_file_index(document, filepath, cache_tree)
+            except Exception as e:
+                LOGGER.debug("Error parsing %s: %s", filepath, e)
+                self._discard_index_update(filepath, token)
+                return False
+            # Only cache results whose file did not change while being read.
+            if stat is not None and file_stat(filepath) == stat:
+                self.index_cache.put(filepath, stat, index)
 
         if require_file_exists and not pathlib.Path(filepath).is_file():
             self._discard_index_update(filepath, token)
@@ -640,12 +791,12 @@ class TclLanguageServer(LanguageServer):
         with self._index_lock:
             if self._index_tokens.get(filepath) != token:
                 return False
-            self.poco_completion[filepath] = list(collector.custom_functions)
-            self.proc_signatures[filepath] = dict(collector.proc_signatures)
-            self.proc_docs[filepath] = docs
-            self.class_indexes[filepath] = classes
-            self.navigation_indexes[filepath] = navigation_index
-            self.variable_indexes[filepath] = (document.version, variable_index)
+            self.poco_completion[filepath] = list(index.completion_items)
+            self.proc_signatures[filepath] = dict(index.proc_signatures)
+            self.proc_docs[filepath] = index.proc_docs
+            self.class_indexes[filepath] = index.classes
+            self.navigation_indexes[filepath] = index.navigation_index
+            self.variable_indexes[filepath] = (document.version, index.variable_index)
             self._committed_index_versions[filepath] = document.version
             self._invalidate_workspace_caches_locked()
         return True

server/src/tools/def_navigation.py

@@ -0,0 +1,191 @@
+"""Navigation between Tcl code and the block templates and addresses of .def files."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import lsprotocol.types as lsp
+
+from tools.def_symbols import ADDRESS, BLOCK_TEMPLATE, FORMAT, DefDeclaration, DefDocument
+from tools.navigation import FileSymbolIndex, SymbolOccurrence
+
+DefTarget = tuple[str, str]
+_KIND_LABELS = {BLOCK_TEMPLATE: "Block template", ADDRESS: "Address", FORMAT: "Format"}
+# Address properties in display order; others follow as declared.
+_ADDRESS_PROPERTIES = (
+    ("FORMAT", "Format"),
+    ("LEADER", "Leader"),
+    ("TRAILER", "Trailer"),
+    ("MIN", "Min"),
+    ("MAX", "Max"),
+    ("FORCE", "Modality"),
+    ("ZERO_FORMAT", "Zero format"),
+    ("INCREMENTAL", "Incremental"),
+    ("OMIT", "Omit"),
+)
+_MODALITY = {
+    "OFF": "modal, output only on change",
+    "ONCE": "output once, then modal",
+    "ALWAYS": "non-modal, always output",
+}
+
+
+def _range(line: int, start: int, end: int) -> lsp.Range:
+    return lsp.Range(
+        start=lsp.Position(line=line, character=start),
+        end=lsp.Position(line=line, character=end),
+    )
+
+
+def _contains(line: int, start: int, end: int, position: lsp.Position) -> bool:
+    return position.line == line and start <= position.character <= end
+
+
+def def_symbol_at(document: DefDocument, position: lsp.Position) -> tuple[DefTarget, lsp.Range, bool] | None:
+    """Return the block template or address at ``position`` of a .def document.
+
+    The flag tells whether the position is on a declaration.
+    """
+    for declaration in document.declarations:
+        if declaration.kind != FORMAT and _contains(declaration.line, declaration.start, declaration.end, position):
+            return (declaration.kind, declaration.name), _range(declaration.line, declaration.start, declaration.end), True
+    for reference in document.references:
+        if _contains(reference.line, reference.start, reference.end, position):
+            return (reference.kind, reference.name), _range(reference.line, reference.start, reference.end), False
+    return None
+
+
+def _uri(path: str, uris: dict[str, str]) -> str:
+    return uris.get(path) or Path(path).as_uri()
+
+
+def def_declarations(documents: dict[str, DefDocument], target: DefTarget) -> list[tuple[str, DefDeclaration]]:
+    kind, name = target
+    return [
+        (path, declaration)
+        for path, document in documents.items()
+        for declaration in document.declarations
+        if declaration.kind == kind and declaration.name == name
+    ]
+
+
+def def_definition_locations(
+    documents: dict[str, DefDocument], target: DefTarget, uris: dict[str, str] | None = None
+) -> list[lsp.Location]:
+    uris = uris or {}
+    return [
+        lsp.Location(uri=_uri(path, uris), range=_range(declaration.line, declaration.start, declaration.end))
+        for path, declaration in def_declarations(documents, target)
+    ]
+
+
+def def_reference_locations(
+    documents: dict[str, DefDocument],
+    target: DefTarget,
+    include_declaration: bool,
+    uris: dict[str, str] | None = None,
+) -> list[lsp.Location]:
+    """Return .def occurrences: declarations and addresses used in block templates."""
+    kind, name = target
+    uris = uris or {}
+    locations = def_definition_locations(documents, target, uris) if include_declaration else []
+    for path, document in documents.items():
+        for reference in document.references:
+            if reference.kind == kind and reference.name == name:
+                locations.append(
+                    lsp.Location(uri=_uri(path, uris), range=_range(reference.line, reference.start, reference.end))
+                )
+    return locations
+
+
+def tcl_def_occurrences(
+    indexes: dict[str, FileSymbolIndex], target: DefTarget
+) -> list[tuple[FileSymbolIndex, SymbolOccurrence]]:
+    kind, name = target
+    return [
+        (index, occurrence)
+        for index in indexes.values()
+        for occurrence in index.occurrences
+        if occurrence.identity.kind == kind and occurrence.identity.name == name
+    ]
+
+
+def all_def_target_locations(
+    documents: dict[str, DefDocument],
+    indexes: dict[str, FileSymbolIndex],
+    target: DefTarget,
+    include_declaration: bool,
+    uris: dict[str, str] | None = None,
+) -> list[lsp.Location]:
+    locations = def_reference_locations(documents, target, include_declaration, uris)
+    locations.extend(
+        lsp.Location(uri=index.uri, range=occurrence.range) for index, occurrence in tcl_def_occurrences(indexes, target)
+    )
+    unique = {}
+    for location in locations:
+        key = (location.uri, location.range.start.line, location.range.start.character)
+        unique.setdefault(key, location)
+    return sorted(unique.values(), key=lambda item: (item.uri, item.range.start.line, item.range.start.character))
+
+
+def def_rename_edits(
+    documents: dict[str, DefDocument],
+    indexes: dict[str, FileSymbolIndex],
+    target: DefTarget,
+    new_name: str,
+    uris: dict[str, str] | None = None,
+) -> lsp.WorkspaceEdit | None:
+    """Rename a block template or address in all .def and Tcl files, if it is declared."""
+    if not def_declarations(documents, target):
+        return None
+    changes: dict[str, list[lsp.TextEdit]] = {}
+    for location in all_def_target_locations(documents, indexes, target, True, uris):
+        changes.setdefault(location.uri, []).append(lsp.TextEdit(range=location.range, new_text=new_name))
+    for edits in changes.values():
+        edits.sort(key=lambda edit: (edit.range.start.line, edit.range.start.character), reverse=True)
+    return lsp.WorkspaceEdit(changes=changes)
+
+
+def _escape_cell(value: str) -> str:
+    return value.replace("|", "\\|") or " "
+
+
+def _address_table(declaration: DefDeclaration, formats: dict[str, DefDeclaration]) -> str:
+    properties = dict(declaration.properties)
+    rows = []
+    for key, label in _ADDRESS_PROPERTIES:
+        value = properties.pop(key, None)
+        if value is None:
+            continue
+        cell = f"`{value}`" if value else ""
+        if key == "FORMAT" and value in formats:
+            cell += f" → `{dict(formats[value].properties).get('FORMAT', '')}`"
+        if key == "FORCE":
+            cell += f" ({_MODALITY[value.upper()]})" if value.upper() in _MODALITY else ""
+        rows.append(f"| {label} | {_escape_cell(cell)} |")
+    rows.extend(f"| {key.title()} | {_escape_cell(f'`{value}`' if value else '')} |" for key, value in properties.items())
+    if not rows:
+        return "_No properties_"
+    return "\n".join(["| Property | Value |", "|---|---|", *rows])
+
+
+def def_hover_markdown(documents: dict[str, DefDocument], target: DefTarget) -> str | None:
+    declarations = def_declarations(documents, target)
+    if not declarations:
+        return None
+    formats = {
+        declaration.name: declaration
+        for document in documents.values()
+        for declaration in document.declarations
+        if declaration.kind == FORMAT
+    }
+    kind, name = target
+    sections = []
+    for path, declaration in declarations:
+        header = f"**{_KIND_LABELS[kind]}** `{name}` — {Path(path).name}:{declaration.line + 1}"
+        if kind == ADDRESS:
+            body = _address_table(declaration, formats)
+        else:
+            body = f"```def\n{declaration.text}\n```"
+        sections.append(f"{header}\n\n{body}")
+    return "\n\n---\n\n".join(sections)

server/src/tools/def_symbols.py

@@ -0,0 +1,180 @@
+"""Block templates, addresses and formats declared in NX post definition (.def) files."""
+
+import re
+from dataclasses import dataclass
+from pathlib import Path
+
+BLOCK_TEMPLATE = "block_template"
+ADDRESS = "address"
+FORMAT = "format"
+
+_KINDS = {"BLOCK_TEMPLATE": BLOCK_TEMPLATE, "ADDRESS": ADDRESS, "FORMAT": FORMAT}
+_HEADER_RE = re.compile(r"^\s*(BLOCK_TEMPLATE|ADDRESS|FORMAT)\s+([^\s{]+)")
+# A block template element is an address followed by its expression: X[$mom_pos(0)].
+_ELEMENT_RE = re.compile(r"^\s*([A-Za-z_]\w*)\[")
+_PROPERTY_RE = re.compile(r"^\s*([A-Za-z_]+)\s*(.*?)\s*$")
+
+
+@dataclass(frozen=True)
+class DefDeclaration:
+    kind: str
+    name: str
+    # 0-based line and UTF-16 columns of the name.
+    line: int
+    start: int
+    end: int
+    end_line: int
+    text: str
+    # ADDRESS: body properties such as ("LEADER", '"X"'); FORMAT: (("FORMAT", '"%d"'),).
+    properties: tuple[tuple[str, str], ...] = ()
+
+
+@dataclass(frozen=True)
+class DefReference:
+    """An address used as element of a block template."""
+
+    kind: str
+    name: str
+    line: int
+    start: int
+    end: int
+    container: str
+
+
+@dataclass(frozen=True)
+class DefDocument:
+    declarations: tuple[DefDeclaration, ...] = ()
+    references: tuple[DefReference, ...] = ()
+
+    def names(self, kind: str) -> tuple[str, ...]:
+        return tuple(dict.fromkeys(item.name for item in self.declarations if item.kind == kind))
+
+
+@dataclass(frozen=True)
+class DefSymbols:
+    block_templates: tuple[str, ...] = ()
+    addresses: tuple[str, ...] = ()
+
+
+def _utf16_length(text: str) -> int:
+    return len(text.encode("utf-16-le")) // 2
+
+
+def _is_comment(line: str) -> bool:
+    return line.lstrip().startswith("#")
+
+
+def _body(lines: list[str], header: int, rest: str) -> tuple[int, int, int] | None:
+    """Return (first body line, first body column, closing line) of a braced body.
+
+    The body starts after the first "{" on the header line or on a following
+    line and ends at the next line starting with "}".
+    """
+    if "{" in rest:
+        after = rest.split("{", 1)[1]
+        if "}" in after:
+            return None
+        start = header + 1
+    else:
+        start = header + 1
+        while start < len(lines) and (not lines[start].strip() or _is_comment(lines[start])):
+            start += 1
+        if start >= len(lines) or not lines[start].lstrip().startswith("{"):
+            return None
+        start += 1
+    end = start
+    while end < len(lines) and not lines[end].lstrip().startswith("}"):
+        end += 1
+    return start, 0, min(end, len(lines) - 1)
+
+
+def parse_def_document(source: str) -> DefDocument:
+    """Parse the block templates, addresses and formats of a .def source."""
+    lines = source.splitlines()
+    declarations: list[DefDeclaration] = []
+    references: list[DefReference] = []
+    index = 0
+    while index < len(lines):
+        line = lines[index]
+        match = None if _is_comment(line) else _HEADER_RE.match(line)
+        if match is None:
+            index += 1
+            continue
+
+        kind = _KINDS[match.group(1)]
+        name = match.group(2)
+        start = _utf16_length(line[: match.start(2)])
+        end = start + _utf16_length(name)
+        rest = line[match.end(2) :]
+
+        if kind == FORMAT:
+            declarations.append(
+                DefDeclaration(kind, name, index, start, end, index, line.strip(), (("FORMAT", rest.strip()),))
+            )
+            index += 1
+            continue
+
+        body = _body(lines, index, rest)
+        end_line = index if body is None else body[2]
+        properties: list[tuple[str, str]] = []
+        if body is not None:
+            for number in range(body[0], body[2]):
+                body_line = lines[number]
+                if _is_comment(body_line) or not body_line.strip():
+                    continue
+                if kind == BLOCK_TEMPLATE:
+                    element = _ELEMENT_RE.match(body_line)
+                    if element is not None:
+                        element_start = _utf16_length(body_line[: element.start(1)])
+                        references.append(
+                            DefReference(
+                                ADDRESS,
+                                element.group(1),
+                                number,
+                                element_start,
+                                element_start + _utf16_length(element.group(1)),
+                                name,
+                            )
+                        )
+                else:
+                    prop = _PROPERTY_RE.match(body_line)
+                    if prop is not None:
+                        properties.append((prop.group(1).upper(), prop.group(2)))
+
+        declarations.append(
+            DefDeclaration(
+                kind,
+                name,
+                index,
+                start,
+                end,
+                end_line,
+                "\n".join(lines[index : end_line + 1]),
+                tuple(properties),
+            )
+        )
+        index = end_line + 1
+
+    return DefDocument(tuple(declarations), tuple(references))
+
+
+def parse_def_symbols(source: str) -> DefSymbols:
+    """Return the BLOCK_TEMPLATE and ADDRESS names of a .def source in declaration order."""
+    document = parse_def_document(source)
+    return DefSymbols(
+        block_templates=document.names(BLOCK_TEMPLATE),
+        addresses=document.names(ADDRESS),
+    )
+
+
+def read_def_source(path: Path) -> str:
+    data = path.read_bytes()
+    try:
+        return data.decode("utf-8-sig")
+    except UnicodeDecodeError:
+        # Older Windows NX layers use the ANSI code page.
+        return data.decode("cp1252")
+
+
+def read_def_symbols(path: Path) -> DefSymbols:
+    return parse_def_symbols(read_def_source(path))

server/src/tools/file_sourcing.py

@@ -1,6 +1,6 @@
 import xml.etree.ElementTree as ET
 import os
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from typing import List, Optional
 from pathlib import Path
 
@@ -10,6 +10,7 @@ class SourcedFile:
     layer_name: str
     subfolder: Optional[str]
     files: List[str]
+    defined_events: List[str] = field(default_factory=list)
 
 
 def read_psc_file(psc_file: Path) -> List[SourcedFile]:
@@ -34,8 +35,22 @@ def read_psc_file(psc_file: Path) -> List[SourcedFile]:
                 if name:
                     script_names.append(name)
 
+        # DefinedEvents-Filenames (.def files)
+        defined_events = layer.find("DefinedEvents")
+        event_names = []
+        if defined_events is not None:
+            for filename in defined_events.findall("Filename"):
+                name = filename.attrib.get("Name")
+                if name:
+                    event_names.append(name)
+
         layer_info_list.append(
-            SourcedFile(layer_name=layer_name, subfolder=subfolder, files=script_names)
+            SourcedFile(
+                layer_name=layer_name,
+                subfolder=subfolder,
+                files=script_names,
+                defined_events=event_names,
+            )
         )
     return layer_info_list
 
@@ -44,20 +59,30 @@ def get_all_psc_files(root_path: Path) -> list[Path]:
     return sorted(root_path.rglob("*.psc"), key=lambda path: str(path).casefold())
 
 
-def psc_script_files(psc_file: Path) -> list[Path]:
-    """Resolve layer script paths relative to the PSC, preserving load order."""
-    def expanded(value):
-        return Path(os.path.expandvars(value).replace("\\", "/"))
+def _expanded(value) -> Path:
+    return Path(os.path.expandvars(value).replace("\\", "/"))
 
+
+def _layer_files(psc_file: Path, attribute: str, suffix: str) -> list[Path]:
     paths = []
     for layer in read_psc_file(psc_file):
         folder = layer.subfolder or "."
-        base = psc_file.parent / expanded(os.environ.get(folder, folder))
-        for name in layer.files:
-            filename = expanded(name)
+        base = psc_file.parent / _expanded(os.environ.get(folder, folder))
+        for name in getattr(layer, attribute):
+            filename = _expanded(name)
             if not filename.suffix:
-                filename = filename.with_suffix(".tcl")
+                filename = filename.with_suffix(suffix)
             path = (base / filename).resolve()
-            if path.suffix.lower() == ".tcl":
+            if path.suffix.lower() == suffix:
                 paths.append(path)
     return paths
+
+
+def psc_script_files(psc_file: Path) -> list[Path]:
+    """Resolve layer script paths relative to the PSC, preserving load order."""
+    return _layer_files(psc_file, "files", ".tcl")
+
+
+def psc_defined_event_files(psc_file: Path) -> list[Path]:
+    """Resolve the layers' DefinedEvents (.def) paths relative to the PSC."""
+    return _layer_files(psc_file, "defined_events", ".def")

server/src/tools/formatter.py

@@ -12,6 +12,14 @@ class NxFormatter(BaseFormatter):
     while leaving all other formatting behavior unchanged.
     """
 
+    def format_comment(self, comment) -> List[str]:  # type: ignore[override]
+        # "#Comment" -> "# Comment". Leave "#", "##..." separators, "#!" and
+        # comments that already start with whitespace untouched.
+        value = comment.value
+        if value and not value[0].isspace() and value[0] not in "#!":
+            value = " " + value
+        return [f"#{value}"]
+
     def format_braced_expression(self, expr) -> List[str]:  # type: ignore[override]
         # This method mirrors BaseFormatter.format_braced_expression but inserts
         # a line continuation (" \") between continuation lines similar to

server/src/tools/incremental_parse.py

@@ -0,0 +1,156 @@
+"""Reparse only the top-level commands touched by an edit.
+
+Tcl top-level commands are independent once the previous command ended on its
+own line: the parser keeps no state between them. An edit is therefore
+reparsed from the first to the last top-level command it touches, commands
+before it are reused as-is and commands after it are reused with their line
+numbers shifted. Whenever that assumption could break, the caller falls back
+to a full parse.
+"""
+
+from __future__ import annotations
+
+import copy
+from collections.abc import Callable
+
+from tclint.syntax_tree import Node, Script
+from tclint.violations import Violation
+
+ParseChunk = Callable[[str, tuple[int, int]], tuple[Script, list[Violation]]]
+
+
+def normalize_newlines(source: str) -> str:
+    """Match the universal newline handling of the tclint parser."""
+    return source.replace("\r\n", "\n").replace("\r", "\n")
+
+
+def _shifted_tree(node: Node, delta: int) -> Node:
+    """Copy a subtree with its line numbers moved by `delta`.
+
+    Cached trees may still be read by other requests, so nodes are never
+    mutated. Attributes such as `Command.routine` alias entries of `children`,
+    so every reference is remapped to the same copy.
+    """
+    copies: dict[int, Node] = {}
+
+    def shifted(original: Node) -> Node:
+        existing = copies.get(id(original))
+        if existing is not None:
+            return existing
+        clone = object.__new__(type(original))
+        copies[id(original)] = clone
+        state = dict(original.__dict__)
+        if state.get("line") is not None:
+            state["line"] += delta
+        end = state.get("end_pos")
+        if end is not None:
+            state["end_pos"] = (end[0] + delta, end[1])
+        for key, value in state.items():
+            if isinstance(value, Node):
+                state[key] = shifted(value)
+            elif isinstance(value, (list, tuple)) and value and isinstance(value[0], Node):
+                state[key] = type(value)(shifted(item) for item in value)
+        clone.__dict__.update(state)
+        return clone
+
+    return shifted(node)
+
+
+def _shifted_violation(violation: Violation, delta: int) -> Violation:
+    clone = copy.copy(violation)
+    clone.start = (violation.start[0] + delta, violation.start[1])
+    clone.end = (violation.end[0] + delta, violation.end[1])
+    return clone
+
+
+def reparse(
+    old_source: str,
+    old_tree: Script,
+    old_violations: list[Violation],
+    new_source: str,
+    parse_chunk: ParseChunk,
+) -> tuple[Script, list[Violation]] | None:
+    """Return the tree of `new_source`, or None when a full parse is needed.
+
+    Both sources must already be newline-normalized. `parse_chunk` parses a
+    top-level fragment starting at the given (line, column) and may raise
+    TclSyntaxError, which the caller handles like any failed parse.
+    """
+    if old_source == new_source:
+        return old_tree, list(old_violations)
+
+    # Changed line range (1-indexed); lines outside it are identical. A pure
+    # insertion leaves last_changed_old == first_changed_line - 1.
+    old_lines = old_source.split("\n")
+    new_lines = new_source.split("\n")
+    limit = min(len(old_lines), len(new_lines))
+    same_before = 0
+    while same_before < limit and old_lines[same_before] == new_lines[same_before]:
+        same_before += 1
+    same_after = 0
+    while (
+        same_after < limit - same_before
+        and old_lines[-1 - same_after] == new_lines[-1 - same_after]
+    ):
+        same_after += 1
+
+    first_changed_line = same_before + 1
+    last_changed_old = len(old_lines) - same_after
+    delta = len(new_lines) - len(old_lines)
+
+    commands = old_tree.children
+    if any(command.line is None or command.end_pos is None for command in commands):
+        return None
+
+    # Commands overlapping the changed lines, widened so that no reused
+    # command shares a line with the reparsed range.
+    first = next(
+        (index for index, command in enumerate(commands) if command.end_pos[0] >= first_changed_line),
+        len(commands),
+    )
+    start_line = first_changed_line
+    if first < len(commands):
+        start_line = min(start_line, commands[first].line)
+    while first > 0 and commands[first - 1].end_pos[0] >= start_line:
+        first -= 1
+        start_line = min(start_line, commands[first].line)
+
+    last = first - 1
+    end_line_old = last_changed_old
+    while last + 1 < len(commands) and commands[last + 1].line <= end_line_old:
+        last += 1
+        end_line_old = max(end_line_old, commands[last].end_pos[0])
+    end_line_new = end_line_old + delta
+
+    if end_line_new < start_line - 1 or end_line_new > len(new_lines):
+        return None
+    # A trailing backslash joins a line with the next one across the boundary.
+    if start_line > 1 and new_lines[start_line - 2].endswith("\\"):
+        return None
+    if end_line_new >= start_line and new_lines[end_line_new - 1].endswith("\\"):
+        return None
+
+    chunk_commands: list[Node] = []
+    chunk_violations: list[Violation] = []
+    if end_line_new >= start_line:
+        chunk = "\n".join(new_lines[start_line - 1 : end_line_new])
+        chunk_tree, chunk_violations = parse_chunk(chunk, (start_line, 1))
+        chunk_commands = chunk_tree.children
+
+    reused_after = [_shifted_tree(command, delta) for command in commands[last + 1 :]]
+    tree = Script(
+        *commands[:first],
+        *chunk_commands,
+        *reused_after,
+        pos=(old_tree.line, old_tree.col),
+    )
+    tree.end_pos = (len(new_lines), len(new_lines[-1]) + 1)
+
+    violations = [violation for violation in old_violations if violation.start[0] < start_line]
+    violations += chunk_violations
+    violations += [
+        _shifted_violation(violation, delta)
+        for violation in old_violations
+        if violation.start[0] > end_line_old
+    ]
+    return tree, violations

server/src/tools/index_cache.py

@@ -0,0 +1,128 @@
+"""Persist per-file index results across server restarts.
+
+Entries are keyed by path and validated by the file's size and mtime. The
+whole cache is tied to a fingerprint of the code that produced it: the
+indexing sources of this server, the bundled tclint sources and the versions
+of all bundled libraries. Any change to them, including a tclint update or a
+local patch, discards the cache instead of loading stale results.
+"""
+
+from __future__ import annotations
+
+import hashlib
+import logging
+import os
+import pathlib
+import pickle
+import sys
+import tempfile
+import threading
+import zlib
+from typing import Any
+
+LOGGER = logging.getLogger(__name__)
+
+# Bump when the cached data layout changes without a source change above.
+CACHE_FORMAT = 1
+CACHE_FILE = "index-cache.pickle.z"
+
+_SRC_DIR = pathlib.Path(__file__).resolve().parent.parent
+_LIBS_DIR = _SRC_DIR.parent / "libs"
+
+FileStat = tuple[int, int]
+
+
+def code_fingerprint() -> str:
+    digest = hashlib.sha256()
+    digest.update(f"{CACHE_FORMAT}|{sys.version}".encode())
+    sources = [
+        _SRC_DIR / "lsp_tclserver.py",
+        *sorted((_SRC_DIR / "tools").glob("*.py")),
+        *sorted((_SRC_DIR / "plugins").glob("*.py")),
+        *sorted((_LIBS_DIR / "tclint").rglob("*.py")),
+    ]
+    for source in sources:
+        digest.update(source.relative_to(_SRC_DIR.parent).as_posix().encode())
+        digest.update(source.read_bytes())
+    for dist_info in sorted(_LIBS_DIR.glob("*.dist-info")):
+        digest.update(dist_info.name.encode())
+    return digest.hexdigest()
+
+
+def file_stat(path: str) -> FileStat | None:
+    try:
+        stat = os.stat(path)
+    except OSError:
+        return None
+    return stat.st_mtime_ns, stat.st_size
+
+
+class IndexCache:
+    def __init__(self, directory: pathlib.Path | None = None, fingerprint: str = ""):
+        self._path = directory / CACHE_FILE if directory is not None else None
+        self._fingerprint = fingerprint
+        self._entries: dict[str, tuple[FileStat, Any]] = {}
+        self._used: set[str] = set()
+        self._dirty = False
+        self._lock = threading.Lock()
+
+    @classmethod
+    def load(cls, directory: pathlib.Path | str | None) -> IndexCache:
+        """Open the cache in `directory`; without one, nothing is persisted."""
+        if not directory:
+            return cls()
+        cache = cls(pathlib.Path(directory), code_fingerprint())
+        try:
+            with open(cache._path, "rb") as file:
+                fingerprint, entries = pickle.loads(zlib.decompress(file.read()))
+        except FileNotFoundError:
+            return cache
+        except Exception as error:  # A damaged cache must never stop indexing.
+            LOGGER.warning("Ignoring unreadable index cache %s: %s", cache._path, error)
+            cache._dirty = True
+            return cache
+        if fingerprint == cache._fingerprint:
+            cache._entries = entries
+        else:
+            cache._dirty = True
+        return cache
+
+    def get(self, path: str, stat: FileStat) -> Any | None:
+        with self._lock:
+            entry = self._entries.get(path)
+            if entry is None or entry[0] != stat:
+                return None
+            self._used.add(path)
+            return entry[1]
+
+    def put(self, path: str, stat: FileStat, data: Any) -> None:
+        if self._path is None:
+            return
+        with self._lock:
+            self._entries[path] = (stat, data)
+            self._used.add(path)
+            self._dirty = True
+
+    def save(self) -> None:
+        """Write entries used in this session atomically; others are dropped."""
+        if self._path is None:
+            return
+        with self._lock:
+            if not self._dirty and self._used == self._entries.keys():
+                return
+            entries = {path: self._entries[path] for path in self._used if path in self._entries}
+            self._entries = entries
+            self._dirty = False
+        try:
+            self._path.parent.mkdir(parents=True, exist_ok=True)
+            with tempfile.NamedTemporaryFile(dir=self._path.parent, delete=False) as file:
+                data = pickle.dumps((self._fingerprint, entries), protocol=pickle.HIGHEST_PROTOCOL)
+                # Pickled indexes are very repetitive; fast compression cuts ~90%.
+                file.write(zlib.compress(data, 1))
+            os.replace(file.name, self._path)
+        except Exception as error:
+            LOGGER.warning("Could not write index cache %s: %s", self._path, error)
+            try:
+                os.unlink(file.name)
+            except (OSError, NameError):
+                pass

server/src/tools/inlay_hint.py

@@ -200,7 +200,7 @@ class InlayHintGenerator(Visitor):
 
         walk(tree)
         if self.parameter_names != "none":
-            for call in resolved_method_calls(self.source, self.external_classes):
+            for call in resolved_method_calls(self.source, self.external_classes, tree):
                 if not self._node_intersects_requested_range(call.command):
                     continue
                 parameters = method_parameters(call.parameters)

server/src/tools/navigation.py

@@ -114,6 +114,49 @@ def _name_range(node: Node, raw_name: str, *, variable_sub: bool = False) -> lsp
     )
 
 
+DEF_BLOCK_TEMPLATE = "block_template"
+DEF_ADDRESS = "address"
+DEF_SYMBOL_KINDS = frozenset({DEF_BLOCK_TEMPLATE, DEF_ADDRESS})
+
+# NX commands taking .def names: command -> (first argument index, last index or
+# None for all following arguments, kind).
+_DEF_ARGUMENTS: dict[str, tuple[tuple[int, int | None, str], ...]] = {
+    "MOM_do_template": ((0, 0, DEF_BLOCK_TEMPLATE),),
+    "MOM_add_to_block_buffer": ((0, 0, DEF_BLOCK_TEMPLATE),),
+    "MOM_polar_motion": ((0, 0, DEF_BLOCK_TEMPLATE),),
+    "MOM_force_block": ((1, None, DEF_BLOCK_TEMPLATE),),
+    "MOM_ask_address_value": ((0, 0, DEF_ADDRESS),),
+    "MOM_add_to_address_buffer": ((0, 0, DEF_ADDRESS),),
+    "MOM_enable_address": ((0, None, DEF_ADDRESS),),
+    "MOM_disable_address": ((0, None, DEF_ADDRESS),),
+    "MOM_force": ((1, None, DEF_ADDRESS),),
+    "MOM_suppress": ((1, None, DEF_ADDRESS),),
+    "MOM_incremental": ((1, None, DEF_ADDRESS),),
+}
+_DEFINITION_ELEMENT_KINDS = {"ADDRESS": DEF_ADDRESS, "BLOCK": DEF_BLOCK_TEMPLATE}
+
+
+def def_argument_kinds(command: Command) -> list[tuple[Node, str]]:
+    """Return the arguments of ``command`` that name a .def block template or address."""
+    routine = _static_contents(command.routine)
+    if routine in {"MOM_ask_definition_element", "MOM_has_definition_element"}:
+        kind = _DEFINITION_ELEMENT_KINDS.get((_static_contents(command.args[0]) or "").upper()) if command.args else None
+        return [(command.args[1], kind)] if kind and len(command.args) >= 2 else []
+    result = []
+    for first, last, kind in _DEF_ARGUMENTS.get(routine or "", ()):
+        for position, argument in enumerate(command.args):
+            if position >= first and (last is None or position <= last):
+                result.append((argument, kind))
+    return result
+
+
+def _def_name(node: Node) -> str | None:
+    name = _static_contents(node)
+    if not name or node.contents_pos is None or any(char.isspace() or char in "$[]{}\\\"" for char in name):
+        return None
+    return name
+
+
 def _node_range(node: Node) -> lsp.Range | None:
     if node.pos is None or node.end_pos is None:
         return None
@@ -265,6 +308,12 @@ def build_file_symbol_index(
     filepath: str, uri: str, tree: Node
 ) -> FileSymbolIndex:
     occurrences: list[SymbolOccurrence] = []
+    # Most occurrences repeat a few identities; sharing one object per identity
+    # keeps the index (and its persistent cache) small.
+    identities: dict[SymbolIdentity, SymbolIdentity] = {}
+
+    def shared(identity: SymbolIdentity | None) -> SymbolIdentity | None:
+        return None if identity is None else identities.setdefault(identity, identity)
 
     def add_proc(
         node: Node,
@@ -274,7 +323,7 @@ def build_file_symbol_index(
         is_definition: bool,
         declaration_range: lsp.Range | None = None,
     ) -> None:
-        identity = _proc_identity(raw_name, scope.namespace)
+        identity = shared(_proc_identity(raw_name, scope.namespace))
         caller = None
         if not is_definition:
             caller = (
@@ -288,14 +337,14 @@ def build_file_symbol_index(
                 fallback_identity=(
                     None
                     if is_definition
-                    else _proc_fallback(raw_name, scope.namespace)
+                    else shared(_proc_fallback(raw_name, scope.namespace))
                 ),
                 range=_name_range(node, raw_name),
                 placeholder=_basename(raw_name),
                 is_definition=is_definition,
                 symbol_kind=lsp.SymbolKind.Function,
                 container_name=_container_name(identity),
-                caller=caller,
+                caller=shared(caller),
                 declaration_range=declaration_range,
             )
         )
@@ -309,7 +358,7 @@ def build_file_symbol_index(
         variable_sub: bool = False,
         identity: SymbolIdentity | None = None,
     ) -> None:
-        symbol_identity = identity or _variable_identity(raw_name, scope)
+        symbol_identity = shared(identity or _variable_identity(raw_name, scope))
         occurrences.append(
             SymbolOccurrence(
                 identity=symbol_identity,
@@ -430,6 +479,23 @@ def build_file_symbol_index(
         if routine:
             add_proc(command.routine, routine, scope, is_definition=False)
 
+        for node, kind in def_argument_kinds(command):
+            name = _def_name(node)
+            if name is None:
+                continue
+            line, column = node.contents_pos
+            occurrences.append(
+                SymbolOccurrence(
+                    identity=shared(SymbolIdentity(kind=kind, name=name)),
+                    range=lsp.Range(
+                        start=lsp.Position(line=line - 1, character=column - 1),
+                        end=lsp.Position(line=line - 1, character=column - 1 + len(name)),
+                    ),
+                    placeholder=name,
+                    symbol_kind=lsp.SymbolKind.Struct if kind == DEF_BLOCK_TEMPLATE else lsp.SymbolKind.Field,
+                )
+            )
+
         declaration_nodes = _variable_declaration_nodes(command)
         declaration_ids = {id(node) for node in declaration_nodes}
         for node in declaration_nodes:
@@ -506,6 +572,15 @@ def resolve_identity(
     return occurrence.identity
 
 
+def _may_resolve_to(occurrence: SymbolOccurrence, identity: SymbolIdentity) -> bool:
+    """Cheap name pre-filter; resolve_identity only returns one of these two."""
+    name = identity.name
+    fallback = occurrence.fallback_identity
+    return occurrence.identity.name == name or (
+        fallback is not None and fallback.name == name
+    )
+
+
 def symbol_at_position(
     index: FileSymbolIndex,
     position: lsp.Position,
@@ -530,6 +605,8 @@ def matching_occurrences(
     matches = []
     for index in indexes.values():
         for occurrence in index.occurrences:
+            if not _may_resolve_to(occurrence, identity):
+                continue
             if resolve_identity(occurrence, definitions) == identity:
                 matches.append((index, occurrence))
     return matches
@@ -543,6 +620,8 @@ def document_highlights(
     """Return all occurrences of one symbol in the active document."""
     highlights = []
     for occurrence in index.occurrences:
+        if not _may_resolve_to(occurrence, identity):
+            continue
         if resolve_identity(occurrence, definitions) != identity:
             continue
 

server/src/tools/parser.py

@@ -1,7 +1,9 @@
 import io
+import re
 from typing import Optional, Tuple
 from tclint.parser import Parser
 from tclint.commands import CommandArgError
+from tclint.commands.checks import eval as eval_script_args
 from tclint.syntax_tree import (
     BracedWord,
     BareWord,
@@ -13,9 +15,32 @@ from tclint.syntax_tree import (
 from tclint.lexer import TclSyntaxError, Lexer, TOK_EOF
 
 
+_UPLEVEL_LEVEL_RE = re.compile(r"^#?\d+$")
+
+
+def _uplevel(args, parser):
+    """uplevel ?level? arg ?arg ...?"""
+    # ref: https://www.tcl.tk/man/tcl/TclCmd/uplevel.html
+    if len(args) == 0:
+        raise CommandArgError("not enough args to 'uplevel': got 0, expected at least 1")
+
+    # The level can only be omitted when the first arg doesn't look like one.
+    # A non-literal first arg (e.g. $level) is treated as a level as well.
+    level = []
+    if len(args) > 1:
+        first = args[0].contents
+        if first is None or _UPLEVEL_LEVEL_RE.match(first):
+            level = args[0:1]
+
+    return level + eval_script_args(args[len(level) :], parser, "uplevel")
+
+
 class CustomParser(Parser):
     def __init__(self, debug=False, command_plugins=None):
         super().__init__(debug, command_plugins)
+        # tclint only checks the arg count of uplevel; parse its body as a script
+        # so it gets formatted and linted like eval/namespace eval bodies.
+        self._commands = {**self._commands, "uplevel": _uplevel}
         # Used to normalize newlines consistently with open()'s universal newlines mode.
         self._decoder = io.IncrementalNewlineDecoder(None, True)
 

server/src/tools/semantic_tokens.py

@@ -4,7 +4,7 @@ from typing import List
 import attrs
 from common.load_data import standard_items
 from tclint.commands.plugins import PluginManager
-from tclint.syntax_tree import BareWord, Command, QuotedWord, Visitor
+from tclint.syntax_tree import BareWord, BracedWord, Command, QuotedWord, Visitor
 from tools.variable_names import variable_name
 from tools.tcloo_symbols import class_symbols
 from tools.tcloo_completion import _analyze
@@ -173,6 +173,15 @@ class _Highlighter(Visitor):
     def visit_command(self, command: Command):
         routine = command.routine
 
+        # Stored procedure names in braced lappend arguments use the same
+        # highlighting as calls, without treating the literal as executable Tcl.
+        if routine.contents in {"lappend", "::lappend"}:
+            for argument in command.args:
+                if (isinstance(argument, BracedWord)
+                        and argument.contents in self._custom_function_names | _STANDARD_PROC_NAMES):
+                    line, col = argument.contents_pos
+                    self._append_token((line - 1, col - 1), len(argument.contents), "function", [])
+
         # Highlight functions (custom or standard) when used as the routine
         name = getattr(routine, "contents", None)
         if name:

server/src/tools/tcl_command_completion.py

@@ -24,6 +24,10 @@ class DynamicCompletionKind(Enum):
     PROCEDURE = "procedure"
     NAMESPACE = "namespace"
     PATH = "path"
+    BLOCK_TEMPLATE = "block_template"
+    ADDRESS = "address"
+    # A variable substituted as a value, inserted with a leading "$".
+    VALUE = "value"
 
 
 @dataclass(frozen=True)
@@ -424,6 +428,9 @@ for _string_class in STRING_CLASSES:
 
 VALUES_BY_POSITION: dict[tuple[tuple[str, ...], int], tuple[str, ...]] = {
     (("array", "names"), 3): ("-exact", "-glob", "-regexp"),
+    (("MOM_force",), 1): ("Always", "Once", "Off"),
+    (("MOM_suppress",), 1): ("Always", "Once", "Off"),
+    (("MOM_do_template",), 2): ("CREATE", "BUFFER"),
     (("close",), 2): ("read", "write"),
     (("open",), 2): ("r", "r+", "w", "w+", "a", "a+"),
     (("package", "prefer"), 2): ("latest", "stable"),
@@ -468,6 +475,15 @@ DYNAMIC_COMPLETION_RULES = (
     DynamicCompletionRule(("namespace", "origin"), frozenset({2}), DynamicCompletionKind.PROCEDURE),
     DynamicCompletionRule(("rename",), frozenset({1}), DynamicCompletionKind.PROCEDURE),
     # Namespace-taking commands.
+    DynamicCompletionRule(("MOM_do_template",), frozenset({1}), DynamicCompletionKind.BLOCK_TEMPLATE),
+    DynamicCompletionRule(("MOM_do_template",), frozenset({2}), DynamicCompletionKind.VALUE),
+    DynamicCompletionRule(("MOM_ask_address_value",), frozenset({1}), DynamicCompletionKind.ADDRESS),
+    DynamicCompletionRule(("MOM_force",), frozenset({1}), DynamicCompletionKind.VALUE),
+    DynamicCompletionRule(("MOM_force",), _REPEATED_SUBCOMMAND_ARGUMENTS, DynamicCompletionKind.ADDRESS),
+    DynamicCompletionRule(("MOM_suppress",), frozenset({1}), DynamicCompletionKind.VALUE),
+    DynamicCompletionRule(("MOM_suppress",), _REPEATED_SUBCOMMAND_ARGUMENTS, DynamicCompletionKind.ADDRESS),
+    DynamicCompletionRule(("MOM_disable_address",), frozenset(range(1, 33)), DynamicCompletionKind.ADDRESS),
+    DynamicCompletionRule(("MOM_enable_address",), _REPEATED_SUBCOMMAND_ARGUMENTS, DynamicCompletionKind.ADDRESS),
     DynamicCompletionRule(("namespace", "children"), frozenset({2}), DynamicCompletionKind.NAMESPACE),
     DynamicCompletionRule(
         ("namespace", "delete"),
@@ -685,13 +701,14 @@ def tcl_argument_completion(source_lines: Sequence[str], position: Position) ->
 
     for (path, argument_index), values in VALUES_BY_POSITION.items():
         if active_index == argument_index and tuple(words[: len(path)]) == path:
-            return TclArgumentCompletion(
-                items=_completion_items(
+            return _merge_dynamic_completion(
+                _completion_items(
                     values,
                     CompletionItemKind.Value,
                     f"{' '.join(path)} value",
                 ),
-                active_prefix=active_prefix,
+                dynamic_completion,
+                active_prefix,
             )
 
     for path in sorted(OPTIONS_BY_PATH, key=len, reverse=True):

server/src/tools/tcloo_arguments.py

@@ -38,14 +38,14 @@ def method_parameters(parameters: str) -> list[MethodParameter]:
         return []
 
 
-def method_signature_help(source: str, position: lsp.Position, external_classes=None) -> lsp.SignatureHelp | None:
+def method_signature_help(source: str, position: lsp.Position, external_classes=None, tree=None) -> lsp.SignatureHelp | None:
     lines = source.split("\n")
     if position.line >= len(lines):
         return None
     # AST columns are codepoints; LSP columns are UTF-16 code units.
     prefix = lines[position.line].encode("utf-16-le")[:position.character * 2].decode("utf-16-le", errors="ignore")
     cursor = (position.line, len(prefix))
-    candidates = [call for call in resolved_method_calls(source, external_classes)
+    candidates = [call for call in resolved_method_calls(source, external_classes, tree)
                   if _contains_cursor(call.command, lines, cursor)]
     if not candidates:
         return None

server/src/tools/tcloo_completion.py

@@ -1,6 +1,6 @@
 """Static TclOO inference using local and indexed classes, without executing Tcl."""
 
-from collections.abc import Sequence
+from collections.abc import Callable, Sequence
 from dataclasses import dataclass, field
 import re
 
@@ -9,8 +9,30 @@ from tclint.lexer import TclSyntaxError
 from tclint.syntax_tree import BracedWord, Command, CommandSub, Script, VarSub
 
 from tools.parser import CustomParser
+from tools.signature_help import _active_argument, _contains_cursor
 from tools.tcl_command_completion import line_prefix_at_position
 
+_LEADING_RECEIVER = re.compile(r"\s*([A-Za-z_]\w*)\s+[\w:]*$")
+
+
+def may_contain_classes(source, external_classes=None) -> bool:
+    """Cheap pre-check: without any class, TclOO analysis yields nothing."""
+    return bool(external_classes) or "oo::class" in source
+
+
+def _may_be_receiver(name, source_lines, external_classes) -> bool:
+    """Whether a bare command word can name a class, an object or `my`.
+
+    Objects and local classes only come from `... create <name>`, so a word
+    never created anywhere cannot resolve and needs no full-document parse.
+    """
+    if name in {"my", "self", "next"}:
+        return True
+    if any(key.rsplit("::", 1)[-1] == name for key in external_classes or ()):
+        return True
+    created = re.compile(rf"\bcreate\s+[{{\"]?(?:[\w:]*::)?{re.escape(name)}\b")
+    return any("create" in line and created.search(line) for line in source_lines)
+
 
 @dataclass
 class ClassInfo:
@@ -74,10 +96,42 @@ def _qualified(name, namespace):
     return name if name.startswith("::") else f"{namespace}::{name}"
 
 
+def _cursor_may_be_method_word(tree, source_lines, position) -> bool:
+    """Whether the innermost command at the cursor is at its first argument.
+
+    The marker parse below can only succeed there, and the current document's
+    tree has the same structure apart from the marker.
+    """
+    line = source_lines[position.line]
+    # AST columns are codepoints; LSP columns are UTF-16 code units.
+    prefix = line.encode("utf-16-le")[:position.character * 2].decode("utf-16-le", errors="ignore")
+    cursor = (position.line, len(prefix))
+    lines = list(source_lines)
+    innermost = None
+
+    def walk(node):
+        nonlocal innermost
+        start, end = getattr(node, "pos", None), getattr(node, "end_pos", None)
+        if start is not None and end is not None and not start[0] - 1 <= cursor[0] <= end[0] - 1:
+            return
+        if isinstance(node, Command) and _contains_cursor(node, lines, cursor):
+            innermost = node
+        for child in node.children:
+            walk(child)
+
+    walk(tree)
+    return innermost is None or _active_argument(innermost, cursor) == 0
+
+
 def tcloo_completions(
     source_lines: Sequence[str], position: lsp.Position, external_classes=None,
+    current_tree: Callable[[], Script | None] | None = None,
 ) -> list[lsp.CompletionItem] | None:
-    """Return receiver-specific methods, or None outside a known OO context."""
+    """Return receiver-specific methods, or None outside a known OO context.
+
+    `current_tree` lazily returns the parsed, unmodified document (or None) so
+    cursors that cannot hold a method name skip the full marker reparse.
+    """
     prefix = line_prefix_at_position(source_lines, position)
     if prefix is None:
         return None
@@ -87,6 +141,19 @@ def tcloo_completions(
     word_start = len(prefix) - len(typed)
     if word_start == 0 or prefix[word_start - 1] not in " \t":
         return None
+    if not external_classes and not any("oo::class" in line for line in source_lines):
+        return None
+    continued = position.line > 0 and source_lines[position.line - 1].endswith("\\")
+    if not continued:
+        # The first word is the command itself, never a method name.
+        if not prefix[:word_start].strip():
+            return None
+        receiver = _LEADING_RECEIVER.match(prefix)
+        if receiver is not None and not _may_be_receiver(receiver.group(1), source_lines, external_classes):
+            return None
+    tree = current_tree() if current_tree is not None else None
+    if tree is not None and not _cursor_may_be_method_word(tree, source_lines, position):
+        return None
     marker = "__nx_tcloo_completion_cursor__"
     lines = list(source_lines)
     suffix = lines[position.line][len(prefix):]
@@ -258,6 +325,9 @@ def _analyze(tree, typed="", marker="", external_classes=None, uri=None, source=
     return classes, result, calls
 
 
-def resolved_method_calls(source, external_classes=None):
-    tree = parse_completion_source(source)
+def resolved_method_calls(source, external_classes=None, tree=None):
+    if not may_contain_classes(source, external_classes):
+        return []
+    if tree is None:
+        tree = parse_completion_source(source)
     return _analyze(tree, external_classes=external_classes)[2] if tree is not None else []

server/src/tools/tcloo_navigation.py

@@ -1,11 +1,14 @@
 """Definition targets for literal TclOO classes and resolved method calls."""
 
-from tools.tcloo_completion import _analyze, name_location, parse_completion_source
+from tools.tcloo_completion import _analyze, may_contain_classes, name_location, parse_completion_source
 from tools.tcloo_symbols import class_symbols
 
 
-def tcloo_definition(source, uri, position, external_classes=None):
-    tree = parse_completion_source(source)
+def tcloo_definition(source, uri, position, external_classes=None, tree=None):
+    if not may_contain_classes(source, external_classes):
+        return None
+    if tree is None:
+        tree = parse_completion_source(source)
     if tree is None:
         return None
     classes, _, calls = _analyze(tree, external_classes=external_classes, uri=uri, source=source)

server/tests/python_tests/test_completion_context.py

@@ -47,20 +47,9 @@ def _document(path: Path, source: str) -> TextDocument:
     )
 
 
-def _completion_server(
-    tmp_path: Path, monkeypatch
-) -> tuple[TclLanguageServer, TextDocument, str]:
+def _completion_server(tmp_path: Path, monkeypatch) -> tuple[TclLanguageServer, TextDocument, str]:
     declared_builtin = standard_items.nx_variables[0].label
-    current_source = (
-        "set globalValue 1\n"
-        "proc localProc {} { return }\n"
-        "proc caller {argument} {\n"
-        f"    global {declared_builtin}\n"
-        "    set localValue 2\n"
-        "    puts $local\n"
-        "    localP\n"
-        "}\n"
-    )
+    current_source = f"set globalValue 1\nproc localProc {{}} {{ return }}\nproc caller {{argument}} {{\n    global {declared_builtin}\n    set localValue 2\n    puts $local\n    localP\n}}\n"
     workspace_source = """set ::workspaceValue 1
 proc workspaceProc {} { return }
 """
@@ -113,14 +102,10 @@ def test_unset_space_shows_options_then_variables(tmp_path, monkeypatch):
         items = _complete(document, lsp.Position(line=1, character=len(tail)))
         labels = {item.label for item in items}
         if tail in {"unset ", "unset -"}:
-            assert labels == {"-nocomplain", "--"}
+            assert labels == {"nocomplain"}
         else:
             assert "globalValue" in labels
             assert "-nocomplain" not in labels
-            if tail == "unset -nocomplain ":
-                assert "--" in labels
-            else:
-                assert "--" not in labels
 
 
 def test_array_keys_complete_in_set_and_substitution(tmp_path: Path, monkeypatch):
@@ -130,19 +115,16 @@ def test_array_keys_complete_in_set_and_substitution(tmp_path: Path, monkeypatch
         "set ::lib_flag(enabled) 1\nset ::lib_flag(external) 1\n",
     )
     assert server.update_poco_completion_for_file(workspace)
-    source = (
-        "set lib_flag(enabled) 0\n"
-        "set lib_flag(empty) 1\n"
-        "set other(wrong) 1\n"
-        "proc hidden {} { set lib_flag(private) 1 }\n"
-        "set lib_flag()\n"
-        "puts $lib_flag(en)\n"
-        "puts 😀; set lib_flag(em\n"
-    )
+    source = "set lib_flag(enabled) 0\nset lib_flag(empty) 1\nset other(wrong) 1\nproc hidden {} { set lib_flag(private) 1 }\nset lib_flag()\nputs $lib_flag(en)\nputs 😀; set lib_flag(em\n"
     current = _document(tmp_path / "arrays-current.tcl", source)
-    server.workspace.put_text_document(lsp.TextDocumentItem(
-        uri=current.uri, language_id="tcl", version=1, text=source,
-    ))
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(
+            uri=current.uri,
+            language_id="tcl",
+            version=1,
+            text=source,
+        )
+    )
     assert server.update_poco_completion_for_file(current)
     items = _complete(current, _position_after(source, "set lib_flag(", 3))
     assert [item.label for item in items] == ["empty", "enabled", "external"]
@@ -179,32 +161,28 @@ def test_dynamic_array_index_keeps_variable_identity(tmp_path: Path, monkeypatch
     assert variable_name(tree.children[3].args[0]) is None
     path = tmp_path / "dynamic.tcl"
     index = build_file_symbol_index(str(path), path.as_uri(), tree)
-    definition = next(
-        item for item in index.occurrences
-        if item.identity.name == "::custom_flag" and item.is_definition
-    )
+    definition = next(item for item in index.occurrences if item.identity.name == "::custom_flag" and item.is_definition)
     assert definition.range.start.character == 4
     assert definition.range.end.character == 15
     assert definition.array_element is None
     assert any(item.identity.name == "::mom_path_name" for item in index.occurrences)
     highlighter = _Highlighter([], {})
     tree.accept(highlighter, recurse=True)
-    assert any(
-        position == (0, 4) and length == 11 and kind == "variable"
-        for position, length, kind, _ in highlighter._tokens
-    )
+    assert any(position == (0, 4) and length == 11 and kind == "variable" for position, length, kind, _ in highlighter._tokens)
     server, _, _ = _completion_server(tmp_path, monkeypatch)
     current = _document(path, source)
-    server.workspace.put_text_document(lsp.TextDocumentItem(
-        uri=current.uri, language_id="tcl", version=1, text=source,
-    ))
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(
+            uri=current.uri,
+            language_id="tcl",
+            version=1,
+            text=source,
+        )
+    )
     assert server.update_poco_completion_for_file(current)
     items = _complete(current, _position_after(source, "puts $custom"))
     assert "custom_flag" in {item.label for item in items}
-    workspace_items = next(
-        items for item_path, items in server.completion_items_by_file_snapshot().items()
-        if server.paths_equal(item_path, str(path))
-    )
+    workspace_items = next(items for item_path, items in server.completion_items_by_file_snapshot().items() if server.paths_equal(item_path, str(path)))
     assert {"quoted_flag", "command_flag"} <= {item.label for item in workspace_items}
 
 
@@ -236,18 +214,25 @@ def test_literal_array_components_complete_around_substitutions(tmp_path: Path,
         offset = marked.index("|")
         line = marked.replace("|", "")
         items = array_element_completions(
-            [line], lsp.Position(line=0, character=offset),
-            server.navigation_snapshot().values(), str(tmp_path / "caller.tcl"),
+            [line],
+            lsp.Position(line=0, character=offset),
+            server.navigation_snapshot().values(),
+            str(tmp_path / "caller.tcl"),
         )
         assert {item.label for item in items} == labels
         edit = next(item.text_edit for item in items if item.label == selected)
         item = next(item for item in items if item.label == selected)
         assert item.insert_text_format == lsp.InsertTextFormat.PlainText
-        assert line[:edit.range.start.character] + edit.new_text + line[edit.range.end.character:] == expected
-    assert array_element_completions(
-        ["set custom_flag(from_move,$::mom"], lsp.Position(line=0, character=31),
-        server.navigation_snapshot().values(), str(tmp_path / "caller.tcl"),
-    ) is None
+        assert line[: edit.range.start.character] + edit.new_text + line[edit.range.end.character :] == expected
+    assert (
+        array_element_completions(
+            ["set custom_flag(from_move,$::mom"],
+            lsp.Position(line=0, character=31),
+            server.navigation_snapshot().values(),
+            str(tmp_path / "caller.tcl"),
+        )
+        is None
+    )
 
 
 def _argument_completion_request(source: str):
@@ -277,9 +262,7 @@ def test_variable_completion_filters_and_ranks_candidates(tmp_path: Path, monkey
     other_builtin = standard_items.nx_variables[1]
     assert declared_builtin.label in by_label
     assert other_builtin.label in by_label
-    assert by_label[declared_builtin.label].documentation == (
-        declared_builtin.documentation
-    )
+    assert by_label[declared_builtin.label].documentation == (declared_builtin.documentation)
     assert by_label["localValue"].sort_text.startswith("000:")
     assert by_label["globalValue"].sort_text.startswith("100:")
     assert by_label["workspaceValue"].sort_text.startswith("200:")
@@ -307,18 +290,9 @@ def test_command_completion_filters_and_ranks_candidates(tmp_path: Path, monkeyp
 
 
 def test_completion_context_handles_nested_commands_and_utf16():
-    assert (
-        completion_context(["set result [work"], lsp.Position(line=0, character=16))
-        == CompletionContext.COMMAND
-    )
-    assert (
-        completion_context(["😀 puts $value"], lsp.Position(line=0, character=14))
-        == CompletionContext.VARIABLE
-    )
-    assert (
-        completion_context(["puts value"], lsp.Position(line=0, character=10))
-        == CompletionContext.GENERAL
-    )
+    assert completion_context(["set result [work"], lsp.Position(line=0, character=16)) == CompletionContext.COMMAND
+    assert completion_context(["😀 puts $value"], lsp.Position(line=0, character=14)) == CompletionContext.VARIABLE
+    assert completion_context(["puts value"], lsp.Position(line=0, character=10)) == CompletionContext.GENERAL
 
 
 def test_string_subcommands_and_compare_options_are_context_aware():
@@ -330,9 +304,7 @@ def test_string_subcommands_and_compare_options_are_context_aware():
         "-length",
         "-nocase",
     }
-    assert _argument_completion_labels("string compare -nocase ") == {
-        "-length"
-    }
+    assert _argument_completion_labels("string compare -nocase ") == {"-length"}
     assert _argument_completion_labels("string compare -length ") is None
 
 
@@ -356,22 +328,14 @@ def test_string_completion_inside_braced_conditions_and_bodies():
         subcommands = _argument_completion_labels(prefix + "[string ")
         assert subcommands is not None
         assert {"compare", "equal", "is"} <= subcommands
-        assert _argument_completion_labels(prefix + "[string compare -") == {
-            "-length", "-nocase"
-        }
-        assert _argument_completion_labels(
-            prefix + "[string compare -nocase "
-        ) == {"-length"}
+        assert _argument_completion_labels(prefix + "[string compare -") == {"-length", "-nocase"}
+        assert _argument_completion_labels(prefix + "[string compare -nocase ") == {"-length"}
 
 
 def test_closed_braced_arguments_do_not_change_completion_context():
     assert _argument_completion_labels("puts {[string compare }") is None
-    assert _argument_completion_labels(
-        "if {[string equal a b]} {string compare "
-    ) == {"-length", "-nocase"}
-    assert _argument_completion_labels(
-        "if {[string equal a b] && [string is integer "
-    ) == {"-failindex", "-strict"}
+    assert _argument_completion_labels("if {[string equal a b]} {string compare ") == {"-length", "-nocase"}
+    assert _argument_completion_labels("if {[string equal a b] && [string is integer ") == {"-failindex", "-strict"}
 
 
 def test_dict_array_namespace_file_and_info_subcommands():
@@ -413,9 +377,7 @@ def test_dict_array_namespace_file_and_info_subcommands():
     assert {"args", "body", "commands", "exists", "procs", "vars"} <= info_items
 
 
-def test_variable_context_still_takes_priority_inside_tcl_command(
-    tmp_path: Path, monkeypatch
-):
+def test_variable_context_still_takes_priority_inside_tcl_command(tmp_path: Path, monkeypatch):
     _, current, source = _completion_server(tmp_path, monkeypatch)
     command_source = source.replace(
         "    puts $local\n",
@@ -437,9 +399,7 @@ def test_variable_context_still_takes_priority_inside_tcl_command(
     assert "localValue" in {item.label for item in items}
 
 
-def test_lsp_completion_returns_only_matching_command_options(
-    tmp_path: Path, monkeypatch
-):
+def test_lsp_completion_returns_only_matching_command_options(tmp_path: Path, monkeypatch):
     _, current, _ = _completion_server(tmp_path, monkeypatch)
     source = "string compare "
     current = _document(tmp_path / "current.tcl", source)
@@ -459,9 +419,7 @@ def test_lsp_completion_returns_only_matching_command_options(
     assert all(item.sort_text.startswith("000:") for item in items)
 
 
-def test_space_trigger_does_not_open_broad_fallback_completion(
-    tmp_path: Path, monkeypatch
-):
+def test_space_trigger_does_not_open_broad_fallback_completion(tmp_path: Path, monkeypatch):
     _, current, _ = _completion_server(tmp_path, monkeypatch)
     source = "set value "
     current = _document(tmp_path / "current.tcl", source)
@@ -550,9 +508,7 @@ def test_path_completion_is_relative_filtered_and_tcl_safe(tmp_path: Path):
     assert items[0].text_edit.range.start.character == len("source ")
 
 
-def test_lsp_source_completion_reads_paths_from_document_directory(
-    tmp_path: Path, monkeypatch
-):
+def test_lsp_source_completion_reads_paths_from_document_directory(tmp_path: Path, monkeypatch):
     server, current, _ = _completion_server(tmp_path, monkeypatch)
     scripts = tmp_path / "scripts"
     scripts.mkdir()
@@ -576,9 +532,7 @@ def test_lsp_source_completion_reads_paths_from_document_directory(
     assert "scripts/ignored.txt" not in labels
 
 
-def test_command_and_dict_for_snippets_use_lsp_snippet_placeholders(
-    tmp_path: Path, monkeypatch
-):
+def test_command_and_dict_for_snippets_use_lsp_snippet_placeholders(tmp_path: Path, monkeypatch):
     _, current, source = _completion_server(tmp_path, monkeypatch)
     command_items = _complete(current, _position_after(source, "localP", occurrence=1))
     command_by_label = {item.label: item for item in command_items}
@@ -595,14 +549,10 @@ def test_command_and_dict_for_snippets_use_lsp_snippet_placeholders(
 
     switch_arguments = _argument_completion_request("switch ")
     assert switch_arguments is not None
-    assert {"switch block", "-exact", "-glob", "-regexp"} <= {
-        item.label for item in switch_arguments.items
-    }
+    assert {"switch block", "-exact", "-glob", "-regexp"} <= {item.label for item in switch_arguments.items}
 
 
-def test_semantic_variable_and_procedure_argument_completion(
-    tmp_path: Path, monkeypatch
-):
+def test_semantic_variable_and_procedure_argument_completion(tmp_path: Path, monkeypatch):
     _, current, source = _completion_server(tmp_path, monkeypatch)
 
     variable_items = _complete(current, _position_after(source, "    set "))
@@ -633,9 +583,7 @@ def test_semantic_variable_and_procedure_argument_completion(
     assert "string" not in procedure_labels
 
 
-def test_namespace_argument_completion_uses_navigation_index(
-    tmp_path: Path, monkeypatch
-):
+def test_namespace_argument_completion_uses_navigation_index(tmp_path: Path, monkeypatch):
     server, current, _ = _completion_server(tmp_path, monkeypatch)
     namespace_source = "namespace eval tools { proc helper {} { return } }\n"
     namespace_document = _document(tmp_path / "namespaces.tcl", namespace_source)

server/tests/python_tests/test_debug_server.py

@@ -1,4 +1,5 @@
 import sys
+import threading
 from pathlib import Path
 
 import pytest
@@ -27,27 +28,46 @@ def test_debug_endpoint_rejects_invalid_port(monkeypatch, port):
         _debug_server._debug_endpoint()
 
 
-def test_connect_debugger_retries_until_adapter_is_ready(monkeypatch):
-    class FakeDebugpy:
-        def __init__(self):
-            self.connect_calls = 0
-            self.wait_calls = 0
+class FakeDebugpy:
+    def __init__(self, refuse=False, block_wait=False):
+        self.refuse = refuse
+        self.block_wait = block_wait
+        self.connect_calls = 0
+        self.wait_calls = 0
 
-        def connect(self, endpoint):
-            assert endpoint == ("127.0.0.1", 5678)
-            self.connect_calls += 1
-            if self.connect_calls < 3:
-                raise ConnectionRefusedError("listener is starting")
+    def connect(self, endpoint):
+        assert endpoint == ("127.0.0.1", 5678)
+        self.connect_calls += 1
+        if self.refuse:
+            raise ConnectionRefusedError("no listener")
 
-        def wait_for_client(self):
-            self.wait_calls += 1
+    def wait_for_client(self):
+        self.wait_calls += 1
+        if self.block_wait:
+            threading.Event().wait()
 
+
+def test_connect_debugger_connects_once_and_waits_for_client():
     fake_debugpy = FakeDebugpy()
-    monkeypatch.setattr(_debug_server.time, "sleep", lambda _seconds: None)
 
-    _debug_server._connect_debugger(
-        fake_debugpy, "127.0.0.1", 5678, timeout=1.0
-    )
+    _debug_server._connect_debugger(fake_debugpy, "127.0.0.1", 5678, timeout=1.0)
 
-    assert fake_debugpy.connect_calls == 3
+    assert fake_debugpy.connect_calls == 1
     assert fake_debugpy.wait_calls == 1
+
+
+def test_connect_debugger_does_not_retry_refused_connection():
+    # debugpy.connect() cannot be called a second time after a refused connection.
+    fake_debugpy = FakeDebugpy(refuse=True)
+
+    with pytest.raises(RuntimeError, match="No debugpy listener"):
+        _debug_server._connect_debugger(fake_debugpy, "127.0.0.1", 5678, timeout=1.0)
+
+    assert fake_debugpy.connect_calls == 1
+
+
+def test_connect_debugger_times_out_on_stale_adapter():
+    fake_debugpy = FakeDebugpy(block_wait=True)
+
+    with pytest.raises(RuntimeError, match="stale debugpy adapter"):
+        _debug_server._connect_debugger(fake_debugpy, "127.0.0.1", 5678, timeout=0.1)

server/tests/python_tests/test_def_navigation.py

@@ -0,0 +1,242 @@
+"""Go to Definition, hover, references and rename between Tcl and .def files."""
+
+from collections import namedtuple
+from pathlib import Path
+
+import lsprotocol.types as lsp  # type: ignore
+from pygls.workspace import Workspace
+
+import lsp_server
+from lsp_tclserver import TclLanguageServer
+from tools.def_symbols import ADDRESS, BLOCK_TEMPLATE, FORMAT, parse_def_document
+
+PSC = """<?xml version="1.0" encoding="UTF-8"?>
+<Configuration>
+  <Sourcing><Sequence>
+    <Layer Name="Service" SubFolder="service">
+      <DefinedEvents><Filename Name="service"/></DefinedEvents>
+    </Layer>
+  </Sequence></Sourcing>
+</Configuration>
+"""
+
+DEF = """MACHINE Default
+
+FORMATTING
+{
+    FORMAT Coordinate "&__4.3_"
+    ADDRESS SPOS
+    {
+        FORMAT      Coordinate
+        FORCE       off
+        MAX         99999.999 Abort
+        MIN         -99999.999 Abort
+        LEADER      "SPOS="
+    }
+    # ADDRESS commented_out
+    BLOCK_TEMPLATE steady_rest
+    {
+        SPOS[$mom_pos(0)]
+        Text[M60]\\opt
+    }
+}
+"""
+
+TCL = """proc MOM_steady {} {
+    MOM_do_template steady_rest
+    MOM_force Once SPOS X
+    MOM_ask_address_value "SPOS"
+    set name steady_rest
+}
+"""
+
+
+def _project(tmp_path: Path, monkeypatch):
+    (tmp_path / "service").mkdir()
+    (tmp_path / "post.psc").write_text(PSC, encoding="utf-8")
+    def_file = tmp_path / "service" / "service.def"
+    def_file.write_text(DEF, encoding="utf-8")
+    tcl_file = tmp_path / "caller.tcl"
+    tcl_file.write_text(TCL, encoding="utf-8")
+
+    server = TclLanguageServer(name="def-navigation-test", version="1", max_workers=1)
+    server.protocol._workspace = Workspace(  # pylint: disable=protected-access
+        root_uri=tmp_path.as_uri(),
+        sync_kind=lsp.TextDocumentSyncKind.Incremental,
+        workspace_folders=[lsp.WorkspaceFolder(uri=tmp_path.as_uri(), name="root")],
+        position_encoding=lsp.PositionEncodingKind.Utf16,
+    )
+    monkeypatch.setattr(lsp_server, "LSP_SERVER", server)
+    server.refresh_psc_scripts([tmp_path])
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(uri=tcl_file.as_uri(), language_id="tcl", version=1, text=TCL)
+    )
+    server.update_poco_completion_for_file(server.workspace.get_text_document(tcl_file.as_uri()))
+    return server, def_file, tcl_file
+
+
+def _position(source: str, needle: str, occurrence: int = 0, offset: int = 1) -> lsp.Position:
+    index = -1
+    for _ in range(occurrence + 1):
+        index = source.index(needle, index + 1)
+    line = source.count("\n", 0, index)
+    column = index - (source.rfind("\n", 0, index) + 1)
+    return lsp.Position(line=line, character=column + offset)
+
+
+def _tcl_params(tcl_file: Path, needle: str, occurrence: int = 0):
+    return lsp.TextDocumentIdentifier(uri=tcl_file.as_uri()), _position(TCL, needle, occurrence)
+
+
+# The client sends custom .def requests as plain JSON; pygls exposes them as namedtuples.
+_Doc = namedtuple("Object", ["uri"])
+_Pos = namedtuple("Object", ["line", "character"])
+_Params = namedtuple("Object", ["textDocument", "position", "text", "includeDeclaration", "newName"])
+
+
+def _def_params(def_file: Path, needle: str, occurrence: int = 0, text: str = DEF, offset: int = 1, **extra):
+    position = _position(text, needle, occurrence, offset)
+    return _Params(
+        _Doc(def_file.as_uri()),
+        _Pos(position.line, position.character),
+        text,
+        extra.get("includeDeclaration", True),
+        extra.get("newName", ""),
+    )
+
+
+def _lines(locations):
+    return sorted((Path(location.uri).name, location.range.start.line, location.range.start.character) for location in locations)
+
+
+def test_parse_def_document_declarations_and_references():
+    document = parse_def_document(DEF)
+    kinds = [(item.kind, item.name) for item in document.declarations]
+    assert kinds == [(FORMAT, "Coordinate"), (ADDRESS, "SPOS"), (BLOCK_TEMPLATE, "steady_rest")]
+    address = document.declarations[1]
+    assert (address.line, address.start, address.end) == (5, 12, 16)
+    assert dict(address.properties)["LEADER"] == '"SPOS="'
+    assert [(ref.name, ref.line, ref.container) for ref in document.references] == [
+        ("SPOS", 16, "steady_rest"),
+        ("Text", 17, "steady_rest"),
+    ]
+    assert document.declarations[2].text.splitlines()[-1].strip() == "}"
+
+
+def test_tcl_goto_definition_of_template_and_address(tmp_path, monkeypatch):
+    _, def_file, tcl_file = _project(tmp_path, monkeypatch)
+    document, position = _tcl_params(tcl_file, "steady_rest")
+    result = lsp_server.goto_definition(lsp.DefinitionParams(text_document=document, position=position))
+    assert _lines(result) == [("service.def", 14, 19)]
+
+    for needle, occurrence in (("SPOS", 0), ("SPOS", 1)):
+        document, position = _tcl_params(tcl_file, needle, occurrence)
+        result = lsp_server.goto_definition(lsp.DefinitionParams(text_document=document, position=position))
+        assert _lines(result) == [("service.def", 5, 12)]
+
+
+def test_tcl_goto_definition_ignores_plain_words_and_unknown_names(tmp_path, monkeypatch):
+    _, _, tcl_file = _project(tmp_path, monkeypatch)
+    # "set name steady_rest" is no template argument.
+    document, position = _tcl_params(tcl_file, "steady_rest", 1)
+    assert lsp_server.goto_definition(lsp.DefinitionParams(text_document=document, position=position)) is None
+    document, position = lsp.TextDocumentIdentifier(uri=tcl_file.as_uri()), _position(TCL, "SPOS X", offset=5)
+    assert lsp_server.goto_definition(lsp.DefinitionParams(text_document=document, position=position)) is None
+
+
+def test_tcl_hover_shows_template_body_and_address_properties(tmp_path, monkeypatch):
+    _, _, tcl_file = _project(tmp_path, monkeypatch)
+    document, position = _tcl_params(tcl_file, "steady_rest")
+    hover = lsp_server.hover(lsp.HoverParams(text_document=document, position=position))
+    assert "Block template" in hover.contents.value
+    assert "SPOS[$mom_pos(0)]" in hover.contents.value
+    assert "```def" in hover.contents.value
+
+    document, position = _tcl_params(tcl_file, "SPOS")
+    value = lsp_server.hover(lsp.HoverParams(text_document=document, position=position)).contents.value
+    assert "| Format | `Coordinate` → `\"&__4.3_\"` |" in value
+    assert '| Leader | `"SPOS="` |' in value
+    assert "| Min | `-99999.999 Abort` |" in value
+    assert "| Max | `99999.999 Abort` |" in value
+    assert "| Modality | `off` (modal, output only on change) |" in value
+
+
+def test_tcl_references_include_def_declaration_and_template_elements(tmp_path, monkeypatch):
+    _, _, tcl_file = _project(tmp_path, monkeypatch)
+    document, position = _tcl_params(tcl_file, "SPOS")
+    result = lsp_server.references(
+        lsp.ReferenceParams(
+            text_document=document,
+            position=position,
+            context=lsp.ReferenceContext(include_declaration=True),
+        )
+    )
+    assert _lines(result) == [
+        ("caller.tcl", 2, 19),
+        ("caller.tcl", 3, 27),
+        ("service.def", 5, 12),
+        ("service.def", 16, 8),
+    ]
+    result = lsp_server.references(
+        lsp.ReferenceParams(
+            text_document=document,
+            position=position,
+            context=lsp.ReferenceContext(include_declaration=False),
+        )
+    )
+    assert ("service.def", 5, 12) not in _lines(result)
+
+
+def test_tcl_rename_updates_def_and_tcl(tmp_path, monkeypatch):
+    _, def_file, tcl_file = _project(tmp_path, monkeypatch)
+    document, position = _tcl_params(tcl_file, "SPOS")
+    prepared = lsp_server.prepare_rename(lsp.PrepareRenameParams(text_document=document, position=position))
+    assert prepared.placeholder == "SPOS"
+
+    edit = lsp_server.rename(lsp.RenameParams(text_document=document, position=position, new_name="STEADY_POS"))
+    edits = {Path(uri).name: [(e.range.start.line, e.range.start.character) for e in items] for uri, items in edit.changes.items()}
+    assert edits == {"caller.tcl": [(3, 27), (2, 19)], "service.def": [(16, 8), (5, 12)]}
+    assert all(e.new_text == "STEADY_POS" for items in edit.changes.values() for e in items)
+
+
+def test_undeclared_names_are_not_renamed(tmp_path, monkeypatch):
+    _, _, tcl_file = _project(tmp_path, monkeypatch)
+    document = lsp.TextDocumentIdentifier(uri=tcl_file.as_uri())
+    position = _position(TCL, "SPOS X", offset=5)
+    assert lsp_server.prepare_rename(lsp.PrepareRenameParams(text_document=document, position=position)) is None
+
+
+def test_def_requests_resolve_declarations_and_elements(tmp_path, monkeypatch):
+    _, def_file, _ = _project(tmp_path, monkeypatch)
+    # Address element inside a block template -> ADDRESS declaration.
+    result = lsp_server.def_definition(_def_params(def_file, "SPOS[", offset=1))
+    assert _lines(result) == [("service.def", 5, 12)]
+
+    hover = lsp_server.def_hover(_def_params(def_file, "steady_rest"))
+    assert "Text[M60]" in hover.contents.value
+
+    references = lsp_server.def_references(_def_params(def_file, "ADDRESS SPOS", offset=9))
+    assert _lines(references) == [
+        ("caller.tcl", 2, 19),
+        ("caller.tcl", 3, 27),
+        ("service.def", 5, 12),
+        ("service.def", 16, 8),
+    ]
+    assert lsp_server.def_hover(_def_params(def_file, "MACHINE")) is None
+
+
+def test_def_requests_use_unsaved_text(tmp_path, monkeypatch):
+    _, def_file, _ = _project(tmp_path, monkeypatch)
+    text = DEF.replace("BLOCK_TEMPLATE steady_rest", "BLOCK_TEMPLATE steady_rest_new")
+    params = _def_params(def_file, "steady_rest_new", text=text, newName="rest")
+    assert lsp_server.def_prepare_rename(params).placeholder == "steady_rest_new"
+    edit = lsp_server.def_rename(params)
+    assert list(edit.changes) == [def_file.as_uri()]
+
+
+def test_def_rename_updates_tcl_callers(tmp_path, monkeypatch):
+    _, def_file, _ = _project(tmp_path, monkeypatch)
+    edit = lsp_server.def_rename(_def_params(def_file, "steady_rest", newName="lunette"))
+    edits = {Path(uri).name: [(e.range.start.line, e.range.start.character) for e in items] for uri, items in edit.changes.items()}
+    assert edits == {"caller.tcl": [(1, 20)], "service.def": [(14, 19)]}
+    assert lsp_server.def_rename(_def_params(def_file, "steady_rest", newName="bad name")) is None

server/tests/python_tests/test_def_symbols.py

@@ -0,0 +1,260 @@
+"""Completion of .def block templates and addresses from PSC DefinedEvents."""
+
+import itertools
+from pathlib import Path
+
+import lsprotocol.types as lsp  # type: ignore
+from pygls.workspace import Workspace
+
+import lsp_server
+from lsp_tclserver import TclLanguageServer
+from tools.def_symbols import parse_def_symbols
+from tools.file_sourcing import psc_defined_event_files
+
+PSC = """<?xml version="1.0" encoding="UTF-8"?>
+<Configuration>
+  <Sourcing><Sequence>
+    <Layer Name="Service" SubFolder="service">
+      <Scripts><Filename Name="service"/></Scripts>
+      <DefinedEvents><Filename Name="service" Processing="auto"/></DefinedEvents>
+    </Layer>
+    <Layer Name="Empty"><DefinedEvents/></Layer>
+  </Sequence></Sourcing>
+</Configuration>
+"""
+
+DEF = """MACHINE Default
+
+FORMATTING
+{
+	ADDRESS SPOS
+	{
+		FORMAT      Coordinate
+	}
+	ADDRESS X {
+	}
+\tBLOCK_TEMPLATE external_subprogram
+\t{
+\t\tText[$lib_spf(value,subprogram_output_name)]
+\t}
+\tBLOCK_TEMPLATE steady_rest
+\t{
+\t\tText[M60]
+\t}
+#\tBLOCK_TEMPLATE commented_out
+}
+"""
+
+
+def _project(tmp_path: Path, monkeypatch):
+    (tmp_path / "service").mkdir()
+    psc = tmp_path / "post.psc"
+    psc.write_text(PSC, encoding="utf-8")
+    (tmp_path / "service" / "service.def").write_text(DEF, encoding="utf-8")
+    (tmp_path / "service" / "service.tcl").write_text("proc svc {} {}\n", encoding="utf-8")
+
+    server = TclLanguageServer(name="block-template-test", version="1", max_workers=1)
+    server.protocol._workspace = Workspace(  # pylint: disable=protected-access
+        root_uri=tmp_path.as_uri(),
+        sync_kind=lsp.TextDocumentSyncKind.Incremental,
+        workspace_folders=[lsp.WorkspaceFolder(uri=tmp_path.as_uri(), name="root")],
+        position_encoding=lsp.PositionEncodingKind.Utf16,
+    )
+    monkeypatch.setattr(lsp_server, "LSP_SERVER", server)
+    server.refresh_psc_scripts([tmp_path])
+    return server, psc
+
+
+_versions = itertools.count(1)
+
+
+def _complete(server, tmp_path: Path, source: str, trigger: str | None = None):
+    uri = (tmp_path / "caller.tcl").as_uri()
+    # A new version per request, the server caches lines by (uri, version).
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(uri=uri, language_id="tcl", version=next(_versions), text=source)
+    )
+    lines = source.split("\n")
+    context = None
+    if trigger is not None:
+        context = lsp.CompletionContext(
+            trigger_kind=lsp.CompletionTriggerKind.TriggerCharacter,
+            trigger_character=trigger,
+        )
+    result = lsp_server.on_completion(
+        lsp.CompletionParams(
+            text_document=lsp.TextDocumentIdentifier(uri=uri),
+            position=lsp.Position(line=len(lines) - 1, character=len(lines[-1])),
+            context=context,
+        )
+    )
+    return sorted(result.items, key=lambda item: item.sort_text or "")
+
+
+def test_parse_def_symbols_ignores_comments():
+    symbols = parse_def_symbols(DEF)
+    assert symbols.block_templates == ("external_subprogram", "steady_rest")
+    assert symbols.addresses == ("SPOS", "X")
+
+
+def test_psc_defined_event_files_resolve_def_paths(tmp_path, monkeypatch):
+    _, psc = _project(tmp_path, monkeypatch)
+    assert psc_defined_event_files(psc) == [(tmp_path / "service" / "service.def").resolve()]
+
+
+def test_mom_do_template_offers_templates_then_variables_on_space(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    items = _complete(server, tmp_path, "set globalValue 1\nMOM_do_template ", trigger=" ")
+    labels = [item.label for item in items]
+    assert labels[:2] == ["external_subprogram", "steady_rest"]
+    assert items[0].detail == "Block template (service.def)"
+    variable = next(item for item in items if item.label == "globalValue")
+    assert variable.insert_text == "$globalValue"
+    assert "svc" not in labels
+
+
+def test_mom_do_template_ranks_templates_before_variables(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    items = _complete(server, tmp_path, "set globalValue 1\nMOM_do_template st")
+    labels = [item.label for item in items]
+    assert labels[:2] == ["external_subprogram", "steady_rest"]
+    assert "globalValue" in labels
+
+
+def test_mom_do_template_dollar_still_completes_variables(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    items = _complete(server, tmp_path, "set globalValue 1\nMOM_do_template $glob")
+    labels = {item.label for item in items}
+    assert "globalValue" in labels
+    assert "steady_rest" not in labels
+
+
+def test_def_change_refreshes_block_templates(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    def_file = tmp_path / "service" / "service.def"
+    def_file.write_text("BLOCK_TEMPLATE new_block\n{\n}\n", encoding="utf-8")
+    lsp_server.did_change_watched_files(lsp.DidChangeWatchedFilesParams(changes=[
+        lsp.FileEvent(uri=def_file.as_uri(), type=lsp.FileChangeType.Changed)]))
+    assert [item.label for item in server.block_template_items()] == ["new_block"]
+    assert server.address_items() == []
+
+
+def test_mom_ask_address_value_offers_addresses_then_variables(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    items = _complete(server, tmp_path, "set globalValue 1\nMOM_ask_address_value ", trigger=" ")
+    labels = [item.label for item in items]
+    assert labels[:2] == ["SPOS", "X"]
+    assert items[0].detail == "Address (service.def)"
+    assert "globalValue" in labels
+    assert "steady_rest" not in labels
+
+
+def test_mom_force_and_suppress_offer_mode_or_variable_then_addresses(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    for command in ("MOM_force", "MOM_suppress"):
+        items = _complete(server, tmp_path, f"set globalValue 1\n{command} ", trigger=" ")
+        labels = [item.label for item in items]
+        assert set(labels[:3]) == {"Always", "Once", "Off"}
+        variable = next(item for item in items if item.label == "globalValue")
+        assert variable.insert_text == "$globalValue"
+        assert "SPOS" not in labels
+
+        for source in (f"{command} Once ", f"{command} Always SPOS "):
+            labels = [item.label for item in _complete(server, tmp_path, source, trigger=" ")]
+            assert labels[:2] == ["SPOS", "X"]
+            assert "Once" not in labels
+
+
+def _edit(items, label):
+    item = next(item for item in items if item.label == label)
+    return item.text_edit.new_text, (item.text_edit.range.start.character, item.text_edit.range.end.character)
+
+
+def test_def_symbols_and_modes_are_inserted_quoted(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    source = "MOM_do_template st"
+    assert _edit(_complete(server, tmp_path, source), "steady_rest") == ('"steady_rest"', (16, 18))
+    source = "MOM_force "
+    assert _edit(_complete(server, tmp_path, source, trigger=" "), "Once") == ('"Once"', (10, 10))
+    source = "MOM_force Once SP"
+    assert _edit(_complete(server, tmp_path, source), "SPOS") == ('"SPOS"', (15, 17))
+
+
+def test_typed_quotes_are_replaced_not_doubled(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    # Opening quote typed by the user.
+    source = 'MOM_ask_address_value "SP'
+    assert _edit(_complete(server, tmp_path, source), "SPOS") == ('"SPOS"', (22, 25))
+    # Closing quote inserted by the editor after the cursor.
+    uri = (tmp_path / "caller.tcl").as_uri()
+    source = 'MOM_ask_address_value "SP"'
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(uri=uri, language_id="tcl", version=next(_versions), text=source)
+    )
+    items = lsp_server.on_completion(
+        lsp.CompletionParams(
+            text_document=lsp.TextDocumentIdentifier(uri=uri),
+            position=lsp.Position(line=0, character=25),
+        )
+    ).items
+    assert _edit(items, "SPOS") == ('"SPOS"', (22, 26))
+
+
+def test_block_list_prefix_offers_keyword_and_stays_incomplete(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    uri = (tmp_path / "caller.tcl").as_uri()
+    source = "MOM_do_template BLOCK_L"
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(uri=uri, language_id="tcl", version=next(_versions), text=source)
+    )
+    result = lsp_server.on_completion(
+        lsp.CompletionParams(
+            text_document=lsp.TextDocumentIdentifier(uri=uri),
+            position=lsp.Position(line=0, character=len(source)),
+        )
+    )
+    assert result.is_incomplete
+    keyword = result.items[0]
+    assert keyword.label == "BLOCK_LIST"
+    assert keyword.command.command == "editor.action.triggerSuggest"
+
+
+def test_block_list_shows_all_templates_quoted(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    items = _complete(server, tmp_path, "set a 1\n    BLOCK_LIST")
+    assert [item.label for item in items] == ["external_subprogram", "steady_rest"]
+    assert _edit(items, "steady_rest") == ('"steady_rest"', (4, 14))
+    assert all(item.filter_text.startswith("BLOCK_LIST") for item in items)
+
+
+def test_block_list_ignores_variables_and_other_words(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    for source in ("set x $BLOCK_LIST", "set x MY_BLOCK_LIST", "set x steady"):
+        labels = [item.label for item in _complete(server, tmp_path, source)]
+        assert "BLOCK_LIST" not in labels
+
+
+def test_addr_list_shows_all_addresses_quoted(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    items = _complete(server, tmp_path, "MOM_force Once ADDR_LIST")
+    assert [item.label for item in items] == ["SPOS", "X"]
+    assert _edit(items, "SPOS") == ('"SPOS"', (15, 24))
+    assert all(item.filter_text.startswith("ADDR_LIST") for item in items)
+
+
+def test_addr_list_prefix_offers_keyword(tmp_path, monkeypatch):
+    server, _ = _project(tmp_path, monkeypatch)
+    uri = (tmp_path / "caller.tcl").as_uri()
+    source = "ADDR"
+    server.workspace.put_text_document(
+        lsp.TextDocumentItem(uri=uri, language_id="tcl", version=next(_versions), text=source)
+    )
+    result = lsp_server.on_completion(
+        lsp.CompletionParams(
+            text_document=lsp.TextDocumentIdentifier(uri=uri),
+            position=lsp.Position(line=0, character=len(source)),
+        )
+    )
+    assert result.is_incomplete
+    assert result.items[0].label == "ADDR_LIST"
+    assert "BLOCK_LIST" not in {item.label for item in result.items}

server/tests/python_tests/test_formatter.py

@@ -0,0 +1,58 @@
+"""Formatting with NxFormatter."""
+
+from tclint.format import FormatterOpts
+from tools.formatter import NxFormatter
+from tools.parser import CustomParser
+
+
+def _format(source: str) -> str:
+    formatter = NxFormatter(
+        FormatterOpts(
+            indent="\t",
+            spaces_in_braces=False,
+            balanced_spaces_in_braces=False,
+            max_blank_lines=500,
+            indent_namespace_eval=True,
+            indent_mixed_tab_size=0,
+            emacs=False,
+            debug_whitespace=False,
+        )
+    )
+    return formatter.format_top(source, CustomParser())
+
+
+def test_uplevel_body_is_indented():
+    source = "proc a {} {\n\tuplevel #0 {\n\tset x 1\n\t\tset y 2\n   }\n}\n"
+    assert _format(source) == "proc a {} {\n\tuplevel #0 {\n\t\tset x 1\n\t\tset y 2\n\t}\n}\n"
+
+
+def test_uplevel_without_level_and_with_variable_level():
+    source = "uplevel {\nset x 1\n}\nuplevel $lvl {\nset y 2\n}\nuplevel set z 3\n"
+    assert _format(source) == (
+        "uplevel {\n\tset x 1\n}\nuplevel $lvl {\n\tset y 2\n}\nuplevel set z 3\n"
+    )
+
+
+def test_comment_gets_space_after_hash():
+    source = (
+        "#Comment\n"
+        "# already spaced\n"
+        "#\tTabbed\n"
+        "#\n"
+        "##########\n"
+        "set x 1 ;#inline\n"
+        "proc a {} {\n"
+        "\t#nested\n"
+        "}\n"
+    )
+    assert _format(source) == (
+        "# Comment\n"
+        "# already spaced\n"
+        "#\tTabbed\n"
+        "#\n"
+        "##########\n"
+        "set x 1 ;# inline\n"
+        "proc a {} {\n"
+        "\t# nested\n"
+        "}\n"
+    )

server/tests/python_tests/test_incremental_parse.py

@@ -0,0 +1,131 @@
+import sys
+from pathlib import Path
+
+import pytest
+
+THIS_DIR = Path(__file__).parent
+SRC_DIR = THIS_DIR.parent.parent / "src"
+if str(SRC_DIR) not in sys.path:
+    sys.path.insert(0, str(SRC_DIR))
+
+from lsp_tclserver import TclLanguageServer  # noqa: E402
+from pygls.workspace.text_document import TextDocument  # noqa: E402
+from tclint.lexer import TclSyntaxError  # noqa: E402
+from tclint.syntax_tree import Node  # noqa: E402
+from tools.incremental_parse import reparse  # noqa: E402
+from tools.parser import CustomParser  # noqa: E402
+
+SOURCE = """\
+# header comment
+set a 1; set b 2
+proc first {x} {
+    global mom_pos
+    if {$x > 0} {
+        MOM_output_literal "first $x"
+    }
+    return [expr {$x + 1}]
+}
+
+proc second {} {
+    set list [list a b \\
+        c d]
+    return $list
+}
+lappend ::handlers {second}
+"""
+
+
+def _parse(text, pos=None):
+    parser = CustomParser()
+    tree = parser.parse(text, pos=pos)
+    return tree, list(parser.violations)
+
+
+def _differences(a, b, path="root"):
+    if type(a) is not type(b):
+        return f"{path}: {type(a).__name__} != {type(b).__name__}"
+    for key in a.__dict__.keys() | b.__dict__.keys():
+        first, second = a.__dict__.get(key), b.__dict__.get(key)
+        if isinstance(first, Node):
+            difference = _differences(first, second, f"{path}.{key}")
+        elif isinstance(first, (list, tuple)) and first and isinstance(first[0], Node):
+            if len(first) != len(second):
+                return f"{path}.{key}: {len(first)} != {len(second)}"
+            difference = next(
+                (d for i, (x, y) in enumerate(zip(first, second)) if (d := _differences(x, y, f"{path}.{key}[{i}]"))),
+                None,
+            )
+        else:
+            difference = None if first == second else f"{path}.{key}: {first!r} != {second!r}"
+        if difference:
+            return difference
+    return None
+
+
+def _violations(violations):
+    return [(str(v.id), v.message, v.start, v.end) for v in violations]
+
+
+@pytest.mark.parametrize("old, new", [
+    ("MOM_output_literal \"first $x\"", "MOM_output_literal \"first $x\" extra"),
+    ("    return $list\n", "    return $list\n    puts done\n"),
+    ("proc second {} {", "\nproc second {} {"),
+    ("set a 1; set b 2\n", ""),
+    ("# header comment\n", "# header comment\nset inserted 0\n"),
+    ("lappend ::handlers {second}\n", "lappend ::handlers {second}\nproc third {} {}\n"),
+    ("        c d]", "        c d e]"),
+    ("global mom_pos", "global mom_pos mom_out_angle_pos"),
+])
+def test_incremental_tree_matches_full_parse(old, new):
+    edited = SOURCE.replace(old, new, 1)
+    assert edited != SOURCE
+    previous = (SOURCE, *_parse(SOURCE))
+    result = reparse(*previous, edited, _parse)
+    assert result is not None
+    expected = _parse(edited)
+    assert _differences(result[0], expected[0]) is None
+    assert _violations(result[1]) == _violations(expected[1])
+
+
+def test_continuation_across_the_edit_forces_full_parse():
+    edited = SOURCE.replace("set a 1; set b 2", "set a 1; set b 2 \\")
+    assert reparse(SOURCE, *_parse(SOURCE), edited, _parse) is None
+
+
+def test_quote_closing_outside_the_edit_is_left_to_the_full_parse():
+    edited = SOURCE.replace("set a 1; set b 2", 'set a "1; set b 2')
+    try:
+        result = reparse(SOURCE, *_parse(SOURCE), edited, _parse)
+    except TclSyntaxError:
+        result = None
+    assert result is None
+
+
+def test_unchanged_commands_are_reused_and_never_mutated():
+    tree, violations = _parse(SOURCE)
+    edited = SOURCE.replace("return $list", "return [lsort $list]")
+    new_tree, _ = reparse(SOURCE, tree, violations, edited, _parse)
+    assert new_tree.children[0] is tree.children[0]
+    # Commands after the edit are shifted copies; the old tree stays valid.
+    inserted = SOURCE.replace("proc first", "\n\nproc first")
+    shifted_tree, _ = reparse(SOURCE, tree, violations, inserted, _parse)
+    assert shifted_tree.children[-1] is not tree.children[-1]
+    assert shifted_tree.children[-1].line == tree.children[-1].line + 2
+    assert tree.children[-1].line == _parse(SOURCE)[0].children[-1].line
+
+
+def test_server_reparses_edits_incrementally(tmp_path, monkeypatch):
+    server = TclLanguageServer(name="incremental-test", version="1", max_workers=1)
+    uri = (tmp_path / "edit.tcl").as_uri()
+    first = server.get_tree(TextDocument(uri=uri, source=SOURCE, version=1, language_id="tcl"))
+
+    parsed_sources = []
+    parse_source = server._parse_source
+    monkeypatch.setattr(server, "_parse_source", lambda text, pos=None: parsed_sources.append(text) or parse_source(text, pos))
+    server.clear_cache_for_uri(uri)
+    edited = SOURCE.replace("return $list", "return [lsort $list]")
+    second = server.get_tree(TextDocument(uri=uri, source=edited, version=2, language_id="tcl"))
+
+    assert parsed_sources and all(text != edited for text in parsed_sources)
+    assert second.children[0] is first.children[0]
+    assert _differences(second, _parse(edited)[0]) is None

server/tests/python_tests/test_index_cache.py

@@ -0,0 +1,109 @@
+import os
+import sys
+from pathlib import Path
+
+THIS_DIR = Path(__file__).parent
+SRC_DIR = THIS_DIR.parent.parent / "src"
+if str(SRC_DIR) not in sys.path:
+    sys.path.insert(0, str(SRC_DIR))
+
+import tools.index_cache as index_cache  # noqa: E402
+from lsp_tclserver import TclLanguageServer  # noqa: E402
+from pygls.workspace.text_document import TextDocument  # noqa: E402
+from tools.index_cache import IndexCache  # noqa: E402
+
+
+def _index_from_disk(server, path: Path) -> bool:
+    return server.update_poco_completion_for_file(
+        TextDocument(uri=path.as_uri(), language_id="tcl"),
+        cache_tree=False,
+        require_file_exists=True,
+        from_disk=True,
+    )
+
+
+def _warm_server(cache_dir: Path) -> TclLanguageServer:
+    server = TclLanguageServer(name="cache-test", version="1", max_workers=1)
+    server.index_cache = IndexCache.load(cache_dir)
+    return server
+
+
+def _fail_build(*_args, **_kwargs):
+    raise AssertionError("file was parsed although it is cached")
+
+
+def test_second_start_uses_cached_index(tmp_path: Path, monkeypatch):
+    source = tmp_path / "post.tcl"
+    source.write_text("proc cached_proc {a b} { return $a }\n", encoding="utf-8")
+    cache_dir = tmp_path / "storage"
+
+    server = _warm_server(cache_dir)
+    assert _index_from_disk(server, source)
+    server.index_cache.save()
+
+    restarted = _warm_server(cache_dir)
+    monkeypatch.setattr(restarted, "_build_file_index", _fail_build)
+    assert _index_from_disk(restarted, source)
+    assert "cached_proc" in restarted.custom_function_names_snapshot()
+    assert restarted.proc_metadata_snapshot(str(source))[0]["cached_proc"] == ["a", "b"]
+
+
+def test_changed_file_is_parsed_again(tmp_path: Path):
+    source = tmp_path / "post.tcl"
+    source.write_text("proc old_proc {} {}\n", encoding="utf-8")
+    cache_dir = tmp_path / "storage"
+    server = _warm_server(cache_dir)
+    assert _index_from_disk(server, source)
+    server.index_cache.save()
+
+    source.write_text("proc new_proc {} {}\n", encoding="utf-8")
+    stat = source.stat()
+    os.utime(source, ns=(stat.st_atime_ns, stat.st_mtime_ns + 1_000_000_000))
+    restarted = _warm_server(cache_dir)
+    assert _index_from_disk(restarted, source)
+    names = restarted.custom_function_names_snapshot()
+    assert "new_proc" in names and "old_proc" not in names
+
+
+def test_code_change_discards_the_cache(tmp_path: Path, monkeypatch):
+    source = tmp_path / "post.tcl"
+    source.write_text("proc cached_proc {} {}\n", encoding="utf-8")
+    cache_dir = tmp_path / "storage"
+    server = _warm_server(cache_dir)
+    assert _index_from_disk(server, source)
+    server.index_cache.save()
+
+    # E.g. an updated tclint: a different fingerprint must not load old entries.
+    monkeypatch.setattr(index_cache, "code_fingerprint", lambda: "other tclint")
+    restarted = _warm_server(cache_dir)
+    built = []
+    build = restarted._build_file_index
+    monkeypatch.setattr(restarted, "_build_file_index", lambda *args: built.append(args) or build(*args))
+    assert _index_from_disk(restarted, source)
+    assert built
+
+
+def test_damaged_cache_is_ignored(tmp_path: Path, monkeypatch):
+    cache_dir = tmp_path / "storage"
+    cache_dir.mkdir()
+    (cache_dir / index_cache.CACHE_FILE).write_bytes(b"not a cache")
+    source = tmp_path / "post.tcl"
+    source.write_text("proc fresh_proc {} {}\n", encoding="utf-8")
+
+    server = _warm_server(cache_dir)
+    assert _index_from_disk(server, source)
+    server.index_cache.save()
+
+    restarted = _warm_server(cache_dir)
+    monkeypatch.setattr(restarted, "_build_file_index", _fail_build)
+    assert _index_from_disk(restarted, source)
+
+
+def test_open_documents_never_touch_the_cache(tmp_path: Path):
+    source = tmp_path / "post.tcl"
+    source.write_text("proc on_disk {} {}\n", encoding="utf-8")
+    server = _warm_server(tmp_path / "storage")
+    unsaved = TextDocument(uri=source.as_uri(), source="proc unsaved {} {}\n", version=3, language_id="tcl")
+    assert server.update_poco_completion_for_file(unsaved)
+    server.index_cache.save()
+    assert not (tmp_path / "storage" / index_cache.CACHE_FILE).exists()

server/tests/python_tests/test_index_stability.py

@@ -267,3 +267,35 @@ def test_variable_and_workspace_request_caches_are_reused(tmp_path: Path):
     assert first_completions is second_completions
     assert first_names is second_names
     assert "cached_proc" in first_names
+
+
+def test_navigation_definitions_are_cached_until_the_index_changes(tmp_path: Path):
+    server = _server()
+    first = _document(tmp_path / "first.tcl", "proc first_proc {} {}")
+    assert server.update_poco_completion_for_file(first)
+
+    indexes, definitions = server.navigation_state()
+    assert server.navigation_state()[1] is definitions
+    assert {identity.name for identity in definitions} >= {"::first_proc"}
+
+    second = _document(tmp_path / "second.tcl", "proc second_proc {} {}")
+    assert server.update_poco_completion_for_file(second)
+    indexes, definitions = server.navigation_state()
+    assert second.path in indexes
+    assert {identity.name for identity in definitions} >= {"::first_proc", "::second_proc"}
+
+
+def test_background_parse_does_not_wait_for_the_request_parser(tmp_path: Path):
+    server = _server()
+    document = _document(tmp_path / "background.tcl", "proc background_proc {} {}")
+    finished = Event()
+
+    def index():
+        assert server.update_poco_completion_for_file(document, cache_tree=False)
+        finished.set()
+
+    with server._parser_lock:
+        with ThreadPoolExecutor(max_workers=1) as executor:
+            executor.submit(index)
+            assert finished.wait(timeout=5)
+    assert "background_proc" in server.custom_function_names_snapshot()

server/tests/python_tests/test_tcloo_arguments.py

@@ -98,3 +98,21 @@ def test_lsp_signature_help_with_unfinished_bracket(tmp_path, monkeypatch):
     ))
     assert result.active_parameter == 1
     assert result.signatures[0].label == "::MCS initValue i value"
+
+
+def test_cached_tree_gives_same_signature_without_reparsing(monkeypatch):
+    import tools.tcloo_completion as tcloo
+
+    source = CLASS + "set mcs [MCS new test]\n$mcs initValue 0 "
+    position = lsp.Position(line=source.count("\n"), character=len(source.rsplit("\n", 1)[-1]))
+    expected = method_signature_help(source, position)
+    tree = CustomParser().parse(source)
+    parse_body = tcloo.parse_completion_source
+
+    def parse(text, pos=None):
+        # Braced class bodies are still parsed on demand, the document is not.
+        assert text != source, "unexpected full-document parse"
+        return parse_body(text, pos)
+
+    monkeypatch.setattr(tcloo, "parse_completion_source", parse)
+    assert method_signature_help(source, position, tree=tree) == expected

server/tests/python_tests/test_tcloo_completion.py

@@ -1,7 +1,7 @@
 import lsprotocol.types as lsp
 import pytest
 
-from tools.tcloo_completion import tcloo_completions
+from tools.tcloo_completion import ClassInfo, tcloo_completions
 
 
 CLASS = """oo::class create MCS {
@@ -164,3 +164,68 @@ def test_namespaced_class_symbols_and_method_body_references():
     assert set(declarations) == {"::geometry::MCS"}
     assert [node.contents for node in references] == ["MCS", "MCS", "geometry::MCS", "::geometry::MCS"]
     assert class_completion_items(tree)[0].label == "geometry::MCS"
+
+
+@pytest.mark.parametrize("code", [
+    "set mcs [MCS new]\nputs |",
+    "set mcs [MCS new]\n    se|",
+    "set mcs [MCS new]\nMOM_output_literal |",
+])
+def test_non_receivers_skip_the_completion_reparse(code, monkeypatch):
+    import tools.tcloo_completion as tcloo
+
+    def fail(*_args, **_kwargs):
+        raise AssertionError("unexpected full-document parse")
+
+    monkeypatch.setattr(tcloo, "parse_completion_source", fail)
+    assert complete(CLASS + code) is None
+
+
+def test_documents_without_classes_skip_the_completion_reparse(monkeypatch):
+    import tools.tcloo_completion as tcloo
+
+    monkeypatch.setattr(tcloo, "parse_completion_source", lambda *_: pytest.fail("parsed"))
+    assert complete("set value [expr 1]\n$value |") is None
+
+
+def test_external_class_receiver_still_completes():
+    source = "Logger |"
+    position = lsp.Position(line=0, character=len(source) - 1)
+    items = tcloo_completions([source.replace("|", "")], position, {"::Logger": ClassInfo()})
+    assert {item.label for item in items} == {"new", "create"}
+
+
+def complete_with_tree(source):
+    from tclint.lexer import TclSyntaxError
+    from tools.parser import CustomParser
+
+    offset = source.index("|")
+    before = source[:offset]
+    position = lsp.Position(line=before.count("\n"), character=len(before.rsplit("\n", 1)[-1].encode("utf-16-le")) // 2)
+    text = source.replace("|", "")
+    try:
+        tree = CustomParser().parse(text)
+    except TclSyntaxError:
+        tree = None
+    return tcloo_completions(text.splitlines(), position, current_tree=lambda: tree)
+
+
+@pytest.mark.parametrize("code", [
+    "set mcs [MCS new]\n$mcs |",
+    "MCS create instance\ninstance |",
+    "set mcs [[MCS new] initOrg 1 2 3]\n$mcs |",
+    "proc run {} {set mcs [MCS new]; $mcs |}",
+    "set mcs [MCS new]\nputs [$mcs |]",
+    "set mcs [MCS new]\nputs [$mcs |",
+    "[MCS new] |",
+    "set mcs [MCS new]\n$mcs initV|alue",
+])
+def test_cached_tree_keeps_method_completions(code):
+    assert "initValue" in {item.label for item in complete_with_tree(CLASS + code)}
+
+
+def test_cached_tree_skips_reparse_outside_first_argument(monkeypatch):
+    import tools.tcloo_completion as tcloo
+
+    monkeypatch.setattr(tcloo, "parse_completion_source", lambda *_: pytest.fail("parsed"))
+    assert complete_with_tree(CLASS + "set mcs [MCS new]\nif {$mcs ne {}} |{ puts 1 }") is None