python lsp

server/libs/pygls/protocol/lsp_meta.py

@@ -0,0 +1,51 @@
+import functools
+import logging
+from pygls.constants import ATTR_FEATURE_TYPE
+from pygls.feature_manager import assign_help_attrs
+
+
+logger = logging.getLogger(__name__)
+
+
+def call_user_feature(base_func, method_name):
+    """Wraps generic LSP features and calls user registered feature
+    immediately after it.
+    """
+
+    @functools.wraps(base_func)
+    def decorator(self, *args, **kwargs):
+        ret_val = base_func(self, *args, **kwargs)
+
+        try:
+            user_func = self.fm.features[method_name]
+            self._execute_notification(user_func, *args, **kwargs)
+        except KeyError:
+            pass
+        except Exception:
+            logger.exception(
+                'Failed to handle user defined notification "%s": %s', method_name, args
+            )
+
+        return ret_val
+
+    return decorator
+
+
+class LSPMeta(type):
+    """Wraps LSP built-in features (`lsp_` naming convention).
+
+    Built-in features cannot be overridden but user defined features with
+    the same LSP name will be called after them.
+    """
+
+    def __new__(mcs, cls_name, cls_bases, cls):
+        for attr_name, attr_val in cls.items():
+            if callable(attr_val) and hasattr(attr_val, "method_name"):
+                method_name = attr_val.method_name
+                wrapped = call_user_feature(attr_val, method_name)
+                assign_help_attrs(wrapped, method_name, ATTR_FEATURE_TYPE)
+                cls[attr_name] = wrapped
+
+                logger.debug('Added decorator for lsp method: "%s"', attr_name)
+
+        return super().__new__(mcs, cls_name, cls_bases, cls)