Fix detection of LanguageServer type annotation when future annotations are used

CHANGELOG.md

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning][semver].
 
 - `pygls` no longer overrides the event loop for the current thread when given an explicit loop to use. ([#334])
 - Fixed `MethodTypeNotRegisteredError` when registering a `TEXT_DOCUMENT_DID_SAVE` feature with options. ([#338])
+- Fixed detection of `LanguageServer` type annotations when using string-based annotations. ([#352])
 
 [#328]: https://github.com/openlawlibrary/pygls/issues/328
 [#334]: https://github.com/openlawlibrary/pygls/issues/334

CONTRIBUTORS.md

@@ -21,3 +21,4 @@
 - [Tomoya Tanjo](https://github.com/tom-tan)
 - [bollwyvl](https://github.com/bollwyvl)
 - [yorodm](https://github.com/yorodm)
+- [Zanie Blue](https://github.com/zanieb)

pygls/feature_manager.py

@@ -19,7 +19,7 @@
 import inspect
 import itertools
 import logging
-from typing import Any, Callable, Dict, Optional
+from typing import Any, Callable, Dict, Optional, get_type_hints
 
 from pygls.constants import (ATTR_COMMAND_TYPE, ATTR_EXECUTE_IN_THREAD, ATTR_FEATURE_TYPE,
                              ATTR_REGISTERED_NAME, ATTR_REGISTERED_TYPE, PARAM_LS)
@@ -49,7 +49,7 @@ def has_ls_param_or_annotation(f, annotation):
     try:
         sig = inspect.signature(f)
         first_p = next(itertools.islice(sig.parameters.values(), 0, 1))
-        return first_p.name == PARAM_LS or first_p.annotation is annotation
+        return first_p.name == PARAM_LS or get_type_hints(f)[first_p.name] == annotation
     except Exception:
         return False
 

tests/test_feature_manager.py

@@ -33,19 +33,23 @@
 from typeguard import TypeCheckError
 from typeguard._utils import qualified_name
 
+class Temp:
+    pass
 
-def test_has_ls_param_or_annotation():
-    class Temp:
-        pass
 
+def test_has_ls_param_or_annotation():
     def f1(ls, a, b, c):
         pass
 
     def f2(temp: Temp, a, b, c):
         pass
 
+    def f3(temp: "Temp", a, b, c):
+        pass
+
     assert has_ls_param_or_annotation(f1, None)
     assert has_ls_param_or_annotation(f2, Temp)
+    assert has_ls_param_or_annotation(f3, Temp)
 
 
 def test_register_command_validation_error(feature_manager):