Catch parser errors instead of error recovery when splitting param comments

jedi/evaluate/pep0484.py

@@ -89,7 +89,11 @@ def _split_mypy_param_declaration(decl_text):
     ['foo', 'Bar[baz, biz]'].
 
     """
-    node = parse(decl_text).children[0]
+    try:
+        node = parse(decl_text, error_recovery=False).children[0]
+    except ParserSyntaxError:
+        debug.warning('Comment annotation is not valid Python: %s' % decl_text)
+        return []
 
     if node.type == 'name':
         return [node.get_code().strip()]

test/completion/pep0484_comments.py

@@ -157,6 +157,11 @@ x = UNKNOWN_NAME2  # type: str
 #? str()
 x
 
+def x(a, b):
+    # type: ([) -> a
+    #?
+    a
+
 class Cat(object):
     def __init__(self, age, friends, name):
         # type: (int, List[Dog], str) -> None