Fix the weird py__path__ behavior

jedi/inference/compiled/access.py

@@ -273,7 +273,13 @@ class DirectObjectAccess(object):
         return [self._create_access_path(base) for base in self._obj.__bases__]
 
     def py__path__(self):
-        return self._obj.__path__
+        paths = getattr(self._obj, '__path__', None)
+        # Avoid some weird hacks that would just fail, because they cannot be
+        # used by pickle.
+        if not isinstance(paths, list) \
+                or not all(isinstance(p, (bytes, unicode)) for p in paths):
+            return None
+        return paths
 
     @_force_unicode_decorator
     def get_repr(self):

jedi/inference/compiled/mixed.py

@@ -277,7 +277,7 @@ def _create(inference_state, access_handle, parent_context, *args):
                 file_io=file_io,
                 string_names=string_names,
                 code_lines=code_lines,
-                is_package=hasattr(compiled_object, 'py__path__'),
+                is_package=compiled_object.is_package,
             ).as_context()
             if name is not None:
                 inference_state.module_cache.add(string_names, ValueSet([module_context]))

jedi/inference/compiled/value.py

@@ -83,9 +83,14 @@ class CompiledObject(Value):
             for access in self.access_handle.py__bases__()
         )
 
-    @CheckAttribute()
     def py__path__(self):
-        return map(cast_path, self.access_handle.py__path__())
+        paths = self.access_handle.py__path__()
+        if paths is None:
+            return None
+        return map(cast_path, paths)
+
+    def is_package(self):
+        return self.py__path__() is not None
 
     @property
     def string_names(self):

jedi/inference/gradual/typeshed.py

@@ -206,12 +206,7 @@ def _try_to_load_stub(inference_state, import_names, python_value_set,
     # 4. Try to load pyi file somewhere if python_value_set was not defined.
     if not python_value_set:
         if parent_module_value is not None:
-            try:
-                method = parent_module_value.py__path__
-            except AttributeError:
-                check_path = []
-            else:
-                check_path = method()
+            check_path = parent_module_value.py__path__() or []
             # In case import_names
             names_for_path = (import_names[-1],)
         else:

jedi/inference/imports.py

@@ -400,28 +400,26 @@ def import_module(inference_state, import_names, parent_module_value, sys_path):
         if is_pkg is None:
             return NO_VALUES
     else:
-        try:
-            method = parent_module_value.py__path__
-        except AttributeError:
-            # The module is not a package.
+        paths = parent_module_value.py__path__()
+        if paths is None:
+            # The module might not be a package.
             return NO_VALUES
+
+        for path in paths:
+            # At the moment we are only using one path. So this is
+            # not important to be correct.
+            if not isinstance(path, list):
+                path = [path]
+            file_io_or_ns, is_pkg = inference_state.compiled_subprocess.get_module_info(
+                string=import_names[-1],
+                path=path,
+                full_name=module_name,
+                is_global_search=False,
+            )
+            if is_pkg is not None:
+                break
         else:
-            paths = method()
-            for path in paths:
-                # At the moment we are only using one path. So this is
-                # not important to be correct.
-                if not isinstance(path, list):
-                    path = [path]
-                file_io_or_ns, is_pkg = inference_state.compiled_subprocess.get_module_info(
-                    string=import_names[-1],
-                    path=path,
-                    full_name=module_name,
-                    is_global_search=False,
-                )
-                if is_pkg is not None:
-                    break
-            else:
-                return NO_VALUES
+            return NO_VALUES
 
     if isinstance(file_io_or_ns, ImplicitNSInfo):
         from jedi.inference.value.namespace import ImplicitNamespaceValue

jedi/inference/value/module.py

@@ -83,12 +83,8 @@ class SubModuleDictMixin(object):
         package).
         """
         names = {}
-        try:
-            method = self.py__path__
-        except AttributeError:
-            pass
-        else:
-            mods = iter_module_names(self.inference_state, method())
+        if self.is_package:
+            mods = iter_module_names(self.inference_state, self.py__path__())
             for name in mods:
                 # It's obviously a relative import to the current module.
                 names[name] = SubModuleName(self, name)
@@ -233,7 +229,15 @@ class ModuleValue(ModuleMixin, TreeValue):
             return self.string_names
         return self.string_names[:-1]
 
-    def _py__path__(self):
+    def py__path__(self):
+        """
+        In case of a package, this returns Python's __path__ attribute, which
+        is a list of paths (strings).
+        Returns None if the module is not a package.
+        """
+        if not self.is_package:
+            return None
+
         # A namespace package is typically auto generated and ~10 lines long.
         first_few_lines = ''.join(self.code_lines[:50])
         # these are strings that need to be used for namespace packages,
@@ -258,23 +262,6 @@ class ModuleValue(ModuleMixin, TreeValue):
         assert file is not None  # Shouldn't be a package in the first place.
         return [os.path.dirname(file)]
 
-    @property
-    def py__path__(self):
-        """
-        Not seen here, since it's a property. The callback actually uses a
-        variable, so use it like::
-
-            foo.py__path__(sys_path)
-
-        In case of a package, this returns Python's __path__ attribute, which
-        is a list of paths (strings).
-        Raises an AttributeError if the module is not a package.
-        """
-        if self.is_package:
-            return self._py__path__
-        else:
-            raise AttributeError('Only packages have __path__ attributes.')
-
     def _as_context(self):
         return ModuleContext(self)
 

jedi/inference/value/namespace.py

@@ -61,6 +61,10 @@ class ImplicitNamespaceValue(Value, SubModuleDictMixin):
     def is_stub(self):
         return False
 
+    @property
+    def is_package(self):
+        return True
+
     def as_context(self):
         return NamespaceContext(self)