Integrate feedback.

Author: davidfstr

mypy/messages.py

@@ -822,15 +822,15 @@ def typeddict_instantiated_with_unexpected_items(self,
     def typeddict_item_name_must_be_string_literal(self,
                                                    typ: TypedDictType,
                                                    context: Context):
-        self.fail('Cannot prove expression is a valid item name. Expected one of {}.'.format(
-            list(typ.items.keys())), context)
+        self.fail('Cannot prove expression is a valid item name; expected one of {}'.format(
+            format_item_name_list(typ.items.keys())), context)
 
     def typeddict_item_name_not_found(self,
                                       typ: TypedDictType,
                                       item_name: str,
                                       context: Context):
-        self.fail('\'{}\' is not a valid item name. Expected one of {}.'.format(
-            item_name, list(typ.items.keys())), context)
+        self.fail('\'{}\' is not a valid item name; expected one of {}'.format(
+            item_name, format_item_name_list(typ.items.keys())), context)
 
 
 def capitalize(s: str) -> str:
@@ -875,6 +875,14 @@ def format_string_list(s: Iterable[str]) -> str:
         return '%s, ... and %s (%i methods suppressed)' % (', '.join(l[:2]), l[-1], len(l) - 3)
 
 
+def format_item_name_list(s: Iterable[str]) -> str:
+    l = list(s)
+    if len(l) <= 5:
+        return '[' + ', '.join(["'%s'" % name for name in l]) + ']'
+    else:
+        return '[' + ', '.join(["'%s'" % name for name in l[:5]]) + ', ...]'
+
+
 def callable_name(type: CallableType) -> str:
     if type.name:
         return type.name

test-data/unit/check-typeddict.test

@@ -369,11 +369,20 @@ reveal_type(p['x'])     # E: Revealed type is 'builtins.int'
 reveal_type(p['y'])     # E: Revealed type is 'builtins.int'
 [builtins fixtures/dict.pyi]
 
+[case testCanGetItemOfTypedDictWithValidBytesOrUnicodeLiteralKey]
+# flags: --python-version 2.7
+from mypy_extensions import TypedDict
+Cell = TypedDict('Cell', {'value': int})
+c = Cell(value=42)
+reveal_type(c['value'])   # E: Revealed type is 'builtins.int'
+reveal_type(c[u'value'])  # E: Revealed type is 'builtins.int'
+[builtins_py2 fixtures/dict.pyi]
+
 [case testCannotGetItemOfTypedDictWithInvalidStringLiteralKey]
 from mypy_extensions import TypedDict
 TaggedPoint = TypedDict('TaggedPoint', {'type': str, 'x': int, 'y': int})
 p = TaggedPoint(type='2d', x=42, y=1337)
-p['z']  # E: 'z' is not a valid item name. Expected one of ['type', 'x', 'y'].
+p['z']  # E: 'z' is not a valid item name; expected one of ['type', 'x', 'y']
 [builtins fixtures/dict.pyi]
 
 [case testCannotGetItemOfTypedDictWithNonLiteralKey]
@@ -382,24 +391,32 @@ from typing import Union
 TaggedPoint = TypedDict('TaggedPoint', {'type': str, 'x': int, 'y': int})
 p = TaggedPoint(type='2d', x=42, y=1337)
 def get_coordinate(p: TaggedPoint, key: str) -> Union[str, int]:
-    return p[key]  # E: Cannot prove expression is a valid item name. Expected one of ['type', 'x', 'y'].
+    return p[key]  # E: Cannot prove expression is a valid item name; expected one of ['type', 'x', 'y']
 [builtins fixtures/dict.pyi]
 
 
 -- Special Method: __setitem__
 
-[case testCanSetItemOfTypedDictWithValidStringLiteralKey]
+[case testCanSetItemOfTypedDictWithValidStringLiteralKeyAndCompatibleValueType]
 from mypy_extensions import TypedDict
 TaggedPoint = TypedDict('TaggedPoint', {'type': str, 'x': int, 'y': int})
 p = TaggedPoint(type='2d', x=42, y=1337)
+p['type'] = 'two_d'
 p['x'] = 1
 [builtins fixtures/dict.pyi]
 
+[case testCannotSetItemOfTypedDictWithIncompatibleValueType]
+from mypy_extensions import TypedDict
+TaggedPoint = TypedDict('TaggedPoint', {'type': str, 'x': int, 'y': int})
+p = TaggedPoint(type='2d', x=42, y=1337)
+p['x'] = 'y'  # E: Argument 2 has incompatible type "str"; expected "int"
+[builtins fixtures/dict.pyi]
+
 [case testCannotSetItemOfTypedDictWithInvalidStringLiteralKey]
 from mypy_extensions import TypedDict
 TaggedPoint = TypedDict('TaggedPoint', {'type': str, 'x': int, 'y': int})
 p = TaggedPoint(type='2d', x=42, y=1337)
-p['z'] = 1  # E: 'z' is not a valid item name. Expected one of ['type', 'x', 'y'].
+p['z'] = 1  # E: 'z' is not a valid item name; expected one of ['type', 'x', 'y']
 [builtins fixtures/dict.pyi]
 
 [case testCannotSetItemOfTypedDictWithNonLiteralKey]
@@ -408,7 +425,7 @@ from typing import Union
 TaggedPoint = TypedDict('TaggedPoint', {'type': str, 'x': int, 'y': int})
 p = TaggedPoint(type='2d', x=42, y=1337)
 def set_coordinate(p: TaggedPoint, key: str, value: int) -> None:
-    p[key] = value  # E: Cannot prove expression is a valid item name. Expected one of ['type', 'x', 'y'].
+    p[key] = value  # E: Cannot prove expression is a valid item name; expected one of ['type', 'x', 'y']
 [builtins fixtures/dict.pyi]