Adapt code into the latest changes

python · gvanrossum · Oct 6, 2020 · May 27, 2020 · May 27, 2020 · May 27, 2020
commit 1e2c3f826e9196ddc2fc457017cbaa8b1a42552d
diff --git a/Doc/reference/compound_stmts.rst b/Doc/reference/compound_stmts.rst
@@ -613,8 +613,7 @@ any valid Python expression.  The presence of annotations does not change the
 semantics of a function.  The annotation values are available as values of
 a dictionary keyed by the parameters' names in the :attr:`__annotations__`
 attribute of the function object. Used annnotations are preserved as strings at
-runtime which enables postponed evaluation (annotations may be evaluated in a
-different order than they appear in the source code).
+runtime which enables postponed evaluation.
 
 .. index:: pair: lambda; expression
 

diff --git a/Lib/test/test_annotations.py b/Lib/test/test_annotations.py
@@ -198,6 +198,7 @@ def test_annotations(self):
         eq('(((a, b)))', '(a, b)')
         eq("(x := 10)")
         eq("f'{(x := 10):=10}'")
+        eq("1 + 2")
         eq("1 + 2 + 3")
 
     def test_fstring_debug_annotations(self):

diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py
@@ -618,7 +618,7 @@ def check_wrapper(self, wrapper, wrapped,
 
 
     def _default_update(self):
-        def f(a:'This is a new annotation'):
+        def f(a: int):
             """This is a test"""
             pass
         f.attr = 'This is also a test'
@@ -635,7 +635,7 @@ def test_default_update(self):
         self.assertEqual(wrapper.__name__, 'f')
         self.assertEqual(wrapper.__qualname__, f.__qualname__)
         self.assertEqual(wrapper.attr, 'This is also a test')
-        self.assertEqual(wrapper.__annotations__['a'], repr('This is a new annotation'))
+        self.assertEqual(wrapper.__annotations__['a'], 'int')
         self.assertNotIn('b', wrapper.__annotations__)
 
     @unittest.skipIf(sys.flags.optimize >= 2,

diff --git a/Lib/test/test_grammar.py b/Lib/test/test_grammar.py
@@ -636,10 +636,6 @@ def f(*x: str): pass
         self.assertEqual(f.__annotations__, {'x': 'str'})
         def f(**x: float): pass
         self.assertEqual(f.__annotations__, {'x': 'float'})
-        def f(x, y: 1+2): pass
-        self.assertEqual(f.__annotations__, {'y': '1 + 2'})
-        def f(x, y: 1+2, /): pass
-        self.assertEqual(f.__annotations__, {'y': '1 + 2'})
         def f(a, b: 1, c: 2, d): pass
         self.assertEqual(f.__annotations__, {'b': '1', 'c': '2'})
         def f(a, b: 1, /, c: 2, d): pass

diff --git a/Lib/test/test_types.py b/Lib/test/test_types.py
@@ -671,8 +671,8 @@ def test_or_type_operator_with_forward(self):
         ForwardBefore = 'Forward' | T
         def forward_after(x: ForwardAfter[int]) -> None: ...
         def forward_before(x: ForwardBefore[int]) -> None: ...
-        assert typing.get_args(typing.get_type_hints(forward_after)['x']) == (int, Forward)
-        assert typing.get_args(typing.get_type_hints(forward_before)['x']) == (int, Forward)
+        assert typing.get_args(typing.get_type_hints(forward_after, localns=locals())['x']) == (int, Forward)
+        assert typing.get_args(typing.get_type_hints(forward_before, localns=locals())['x']) == (int, Forward)
 
     def test_or_type_operator_with_Protocol(self):
         class Proto(typing.Protocol):

diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
@@ -2849,7 +2849,7 @@ def test_get_type_hints_classes(self):
         self.assertEqual(gth(HasForeignBaseClass),
                          {'some_xrepr': XRepr, 'other_a': mod_generics_cache.A,
                           'some_b': mod_generics_cache.B})
-        self.assertEqual(gth(XRepr.__new__),
+        self.assertEqual(gth(XRepr),
                          {'x': int, 'y': int})
         self.assertEqual(gth(mod_generics_cache.B),
                          {'my_inner_a1': mod_generics_cache.B.A,

diff --git a/Lib/typing.py b/Lib/typing.py
@@ -18,6 +18,7 @@
 """
 
 from abc import abstractmethod, ABCMeta
+import ast
 import collections
 import collections.abc
 import contextlib
@@ -469,11 +470,13 @@ class ForwardRef(_Final, _root=True):
     def __init__(self, arg, is_argument=True):
         if not isinstance(arg, str):
             raise TypeError(f"Forward reference must be a string -- got {arg!r}")
-        # since annotations feature is now default, stringified annotations
-        # should be escaped from quotes, or this will result with double
-        # forward refs.
-        if arg[0] in "'\"" and arg[-1] in "'\"":
+
+        # Double-stringified forward references is a result of activating
+        # 'annotations' future by default. This way, we eliminate them on
+        # the runtime.
+        if arg.startswith(("'", '\"')) and arg.endswith(("'", '"')):
             arg = arg[1:-1]
+
         try:
             code = compile(arg, '<string>', 'eval')
         except SyntaxError:
@@ -1366,11 +1369,6 @@ def get_type_hints(obj, globalns=None, localns=None, include_extras=False):
       locals, respectively.
     """
 
-    def resolve(value, globalns, localns=localns):
-        # double resolve forward refs
-        value = _eval_type(value, globalns, localns)
-        return _eval_type(value, globalns, localns)
-
     if getattr(obj, '__no_type_check__', None):
         return {}
     # Classes require a special treatment.
@@ -1387,7 +1385,7 @@ def resolve(value, globalns, localns=localns):
                     value = type(None)
                 if isinstance(value, str):
                     value = ForwardRef(value, is_argument=False)
-                value = resolve(value, base_globals)
+                value = _eval_type(value, base_globals, localns)
                 hints[name] = value
         return hints if include_extras else {k: _strip_annotations(t) for k, t in hints.items()}
 
@@ -1419,7 +1417,7 @@ def resolve(value, globalns, localns=localns):
             value = type(None)
         if isinstance(value, str):
             value = ForwardRef(value)
-        value = resolve(value, globalns)
+        value = _eval_type(value, globalns, localns)
         if name in defaults and defaults[name] is None:
             value = Optional[value]
         hints[name] = value