Implement all remaining Path issues and use it instead of strings

test/test_inference/test_gradual/test_stubs.py

@@ -87,4 +87,4 @@ def test_infer_and_goto(Script, code, full_name, has_stub, has_python, way,
             assert has_python == (not d.is_stub())
         assert d.full_name == full_name
 
-        assert d.is_stub() == d.module_path.endswith('.pyi')
+        assert d.is_stub() == (d.module_path.suffix == '.pyi')

test/test_inference/test_gradual/test_typeshed.py

@@ -14,7 +14,7 @@ TYPESHED_PYTHON3 = os.path.join(typeshed.TYPESHED_PATH, 'stdlib', '3')
 def test_get_typeshed_directories():
     def get_dirs(version_info):
         return {
-            p.path.replace(typeshed.TYPESHED_PATH, '').lstrip(os.path.sep)
+            p.path.replace(str(typeshed.TYPESHED_PATH), '').lstrip(os.path.sep)
             for p in typeshed._get_typeshed_directories(version_info)
         }
 
@@ -52,7 +52,7 @@ def test_keywords_variable(Script):
         assert seq.name == 'Sequence'
         # This points towards the typeshed implementation
         stub_seq, = seq.goto(only_stubs=True)
-        assert typeshed.TYPESHED_PATH in stub_seq.module_path
+        assert str(stub_seq.module_path).startswith(str(typeshed.TYPESHED_PATH))
 
 
 def test_class(Script):
@@ -91,8 +91,12 @@ def test_sys_exc_info(Script):
     none, def_ = Script(code + '[1]').infer()
     # It's an optional.
     assert def_.name == 'BaseException'
+    assert def_.module_path == typeshed.TYPESHED_PATH.joinpath(
+        'stdlib', '2and3', 'builtins.pyi'
+    )
     assert def_.type == 'instance'
     assert none.name == 'NoneType'
+    assert none.module_path is None
 
     none, def_ = Script(code + '[0]').infer()
     assert def_.name == 'BaseException'
@@ -111,7 +115,7 @@ def test_sys_hexversion(Script):
     script = Script('import sys; sys.hexversion')
     def_, = script.complete()
     assert isinstance(def_._name, StubName), def_._name
-    assert typeshed.TYPESHED_PATH in def_.module_path
+    assert str(def_.module_path).startswith(str(typeshed.TYPESHED_PATH))
     def_, = script.infer()
     assert def_.name == 'int'
 
@@ -138,14 +142,14 @@ def test_type_var(Script):
 def test_math_is_stub(Script, code, full_name):
     s = Script(code)
     cos, = s.infer()
-    wanted = os.path.join('typeshed', 'stdlib', '2and3', 'math.pyi')
-    assert cos.module_path.endswith(wanted)
+    wanted = ('typeshed', 'stdlib', '2and3', 'math.pyi')
+    assert cos.module_path.parts[-4:] == wanted
     assert cos.is_stub() is True
     assert cos.goto(only_stubs=True) == [cos]
     assert cos.full_name == full_name
 
     cos, = s.goto()
-    assert cos.module_path.endswith(wanted)
+    assert cos.module_path.parts[-4:] == wanted
     assert cos.goto(only_stubs=True) == [cos]
     assert cos.is_stub() is True
     assert cos.full_name == full_name