Fix docstrings for param completions, fixes #2063, fixes #2109

jedi/api/classes.py

@@ -551,7 +551,7 @@ class BaseName:
         return ''.join(lines[start_index:index + after + 1])
 
     def _get_signatures(self, for_docstring=False):
-        if self._name.api_type == 'property':
+        if self._name.api_type in ('property', 'param'):
             return []
         if for_docstring and self._name.api_type == 'statement' and not self.is_stub():
             # For docstrings we don't resolve signatures if they are simple

test/test_api/test_completion.py

@@ -462,3 +462,21 @@ def test_module_completions(Script, module):
 
 def test_whitespace_at_end_after_dot(Script):
     assert 'strip' in [c.name for c in Script('str. ').complete()]
+
+
+def test_param_docstring_in_completion(Script):
+    # From Github #2063
+    code = '''\
+    from typing import Optional
+
+    def func(arg: Optional[int]):
+        pass
+
+    func(arg'''
+    script = Script(code=code)
+    completions = script.complete(
+        line=len(code.splitlines()),
+        column=len(code.splitlines()[-1])
+    )
+    c, = completions
+    assert c.docstring() == ''