Add NewType support to typing.stringify() and restify()

sphinx/util/typing.py

@@ -88,10 +88,14 @@ def is_system_TypeVar(typ: Any) -> bool:
 
 def restify(cls: Optional["Type"]) -> str:
     """Convert python class to a reST reference."""
+    from sphinx.util import inspect  # lazy loading
+
     if cls is None or cls is NoneType:
         return ':obj:`None`'
     elif cls is Ellipsis:
         return '...'
+    elif inspect.isNewType(cls):
+        return ':class:`%s`' % cls.__name__
     elif cls.__module__ in ('__builtin__', 'builtins'):
         return ':class:`%s`' % cls.__name__
     else:
@@ -277,6 +281,8 @@ def _restify_py36(cls: Optional["Type"]) -> str:
 
 def stringify(annotation: Any) -> str:
     """Stringify type annotation object."""
+    from sphinx.util import inspect  # lazy loading
+
     if isinstance(annotation, str):
         if annotation.startswith("'") and annotation.endswith("'"):
             # might be a double Forward-ref'ed type.  Go unquoting.
@@ -285,6 +291,9 @@ def stringify(annotation: Any) -> str:
             return annotation
     elif isinstance(annotation, TypeVar):
         return annotation.__name__
+    elif inspect.isNewType(annotation):
+        # Could not get the module where it defiend
+        return annotation.__name__
     elif not annotation:
         return repr(annotation)
     elif annotation is NoneType:

tests/test_util_typing.py

@@ -10,7 +10,8 @@
 
 import sys
 from numbers import Integral
-from typing import Any, Callable, Dict, Generator, List, Optional, Tuple, TypeVar, Union
+from typing import (Any, Callable, Dict, Generator, List, NewType, Optional, Tuple, TypeVar,
+                    Union)
 
 import pytest
 
@@ -26,6 +27,7 @@ class MyClass2(MyClass1):
 
 
 T = TypeVar('T')
+MyInt = NewType('MyInt', int)
 
 
 class MyList(List[T]):
@@ -92,6 +94,7 @@ def test_restify_type_hints_typevars():
     assert restify(T_co) == ":obj:`tests.test_util_typing.T_co`"
     assert restify(T_contra) == ":obj:`tests.test_util_typing.T_contra`"
     assert restify(List[T]) == ":class:`List`\\ [:obj:`tests.test_util_typing.T`]"
+    assert restify(MyInt) == ":class:`MyInt`"
 
 
 def test_restify_type_hints_custom_class():
@@ -179,6 +182,7 @@ def test_stringify_type_hints_typevars():
     assert stringify(T_co) == "T_co"
     assert stringify(T_contra) == "T_contra"
     assert stringify(List[T]) == "List[T]"
+    assert stringify(MyInt) == "MyInt"
 
 
 def test_stringify_type_hints_custom_class():