Make namespace folders work with stubs

jedi/evaluate/base_context.py

@@ -158,6 +158,9 @@ class Context(HelperContextMixin, BaseContext):
     def is_module(self):
         return False
 
+    def is_namespace(self):
+        return False
+
     def is_compiled(self):
         return False
 

jedi/evaluate/context/namespace.py

@@ -54,6 +54,9 @@ class ImplicitNamespaceContext(Context, SubModuleDictMixin):
     def py__name__(self):
         return self._fullname
 
+    def is_namespace(self):
+        return True
+
     def is_stub(self):
         return False
 

jedi/evaluate/gradual/typeshed.py

@@ -160,12 +160,18 @@ def _try_to_load_stub(evaluator, import_names, actual_context_set,
             pass
         else:
             file_path = method()
-            if file_path is not None and file_path.endswith('.py'):
+            file_paths = []
+            if c.is_namespace():
+                file_paths = [os.path.join(p, '__init__.pyi') for p in c.py__path__()]
+            elif file_path is not None and file_path.endswith('.py'):
+                file_paths = [file_path + 'i']
+
+            for file_path in file_paths:
                 m = _try_to_load_stub_from_file(
                     evaluator,
                     actual_context_set,
                     # The file path should end with .pyi
-                    file_path + 'i',
+                    file_path,
                     import_names
                 )
                 if m is not None:
@@ -186,14 +192,13 @@ def _try_to_load_stub(evaluator, import_names, actual_context_set,
         else:
             check_path = sys_path
             names_for_path = import_names
-        names_for_path = names_for_path[:-1] + (names_for_path[-1] + '.pyi',)
 
         for p in check_path:
             m = _try_to_load_stub_from_file(
                 evaluator,
                 actual_context_set,
-                os.path.join(p, *names_for_path),
-                import_names
+                os.path.join(p, *names_for_path) + '.pyi',
+                import_names,
             )
             if m is not None:
                 return m

test/completion/stub_folder/stub_only_folder/__init__.pyi

@@ -0,0 +1 @@
+in_stub_only_folder: int

test/completion/stub_folder/with_stub_folder/__init__.py

@@ -0,0 +1,2 @@
+in_with_stub_both_folder = 5
+in_with_stub_python_folder = 8

test/completion/stub_folder/with_stub_folder/__init__.pyi

@@ -0,0 +1,2 @@
+in_with_stub_both_folder: str
+in_with_stub_stub_folder: float

test/completion/stubs.py

@@ -1,11 +1,24 @@
-from stub_folder import with_stub, stub_only
+from stub_folder import with_stub, stub_only, with_stub_folder, stub_only_folder
+
+# Just files
 
 #? int()
 stub_only.in_stub_only
-
 #? str()
 with_stub.in_with_stub_both
-#? int()
+#?
 with_stub.in_with_stub_python
 #? float()
 with_stub.in_with_stub_stub
+
+
+# Folders
+
+#? int()
+stub_only_folder.in_stub_only_folder
+#? str()
+with_stub_folder.in_with_stub_both_folder
+#?
+with_stub_folder.in_with_stub_python_folder
+#? float()
+with_stub_folder.in_with_stub_stub_folder