use tclint as parser / formatter

server/libs/tclint/comments.py

@@ -0,0 +1,91 @@
+from collections import defaultdict
+
+from tclint.syntax_tree import Visitor
+from tclint.violations import ALL_RULES, Rule
+
+
+class CommentVisitor(Visitor):
+    """Scans the tree for lint waiver comments."""
+
+    def __init__(self):
+        # line -> [rule]
+        self.ignore_lines = defaultdict(set)
+
+        self._disable_regions = {
+            # rule -> line
+        }
+
+    def run(self, tree, path):
+        self._path = path
+        tree.accept(self, recurse=True)
+
+        # resolve remaining disabled regions
+        last_line = tree.end_pos[0]
+        for rule, start_line in self._disable_regions.items():
+            for line in range(start_line, last_line + 1):
+                self.ignore_lines[line].add(rule)
+
+        return self.ignore_lines
+
+    def visit_comment(self, comment):
+        contents = comment.value.strip()
+
+        if not contents.startswith("tclint-"):
+            return
+
+        split = contents.split(" ", 1)
+
+        command = split[0]
+
+        rule_strs = []
+        if len(split) > 1:
+            rest = split[-1]
+            rule_strs = rest.split("--", 1)[0]
+            rule_strs = rule_strs.replace(" ", "")
+            rule_strs = rule_strs.split(",")
+
+        rules = []
+        if not rule_strs:
+            # default if no rules specified is all violation types
+            rules = ALL_RULES
+        else:
+            for rule in rule_strs:
+                try:
+                    rules.append(Rule(rule))
+                except ValueError:
+                    self._warning(
+                        f"unknown rule '{rule}' provided to '{command}'", comment.pos
+                    )
+
+        if command == "tclint-disable":
+            for rule in rules:
+                # if in dictionary, already disabled - this has no effect
+                if rule not in self._disable_regions:
+                    self._disable_regions[rule] = comment.line
+        elif command == "tclint-disable-line":
+            line = comment.line
+            self.ignore_lines[line].update(rules)
+        elif command == "tclint-disable-next-line":
+            line = comment.line + 1
+            self.ignore_lines[line].update(rules)
+        elif command == "tclint-enable":
+            for rule in rules:
+                if rule in self._disable_regions:
+                    disable_start_line = self._disable_regions[rule]
+                    disable_end_line = comment.line
+
+                    for line in range(disable_start_line, disable_end_line + 1):
+                        self.ignore_lines[line].add(rule)
+
+                    del self._disable_regions[rule]
+        else:
+            self._warning(
+                f"comment starts with '{command}', which looks like a tclint keyword."
+                " Is this a typo?",
+                comment.pos,
+            )
+
+    def _warning(self, message, pos):
+        # TODO: formal warning mechanism
+        prefix = self._path if self._path is not None else "(stdin)"
+        print(f"Warning: {prefix}:{pos[0]}:{pos[1]}: {message}")