From 141947f071cf91b2bfa90a46da36174081ef1587 Mon Sep 17 00:00:00 2001
From: "Michael J. Sullivan" <sully@msully.net>
Date: Fri, 19 Jul 2019 13:42:04 -0700
Subject: [PATCH] In PEP 484 type comments, allow text after "# type: ignore"

This is to support allowing typecheckers to implement ignores for
specific errors, using syntax like `# type: ignore=E1000` or
`# type: ignore[type-mismatch` or some such.
mypy is about to add support for ignoring specific errors following
this design: https://github.com/python/mypy/issues/7239

Support for extra text in type comments was implemented
in CPython as https://bugs.python.org/issue36878
and in typed_ast as https://github.com/python/typed_ast/pull/116.
---
 pyflakes/checker.py                    |  9 +++++----
 pyflakes/test/test_type_annotations.py | 20 ++++++++++++++++++++
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/pyflakes/checker.py b/pyflakes/checker.py
index acc2ae74..7aa10747 100644
--- a/pyflakes/checker.py
+++ b/pyflakes/checker.py
@@ -73,11 +73,12 @@ def getAlternatives(n):
     FOR_TYPES = (ast.For,)
     LOOP_TYPES = (ast.While, ast.For)
 
-# https://github.com/python/typed_ast/blob/55420396/ast27/Parser/tokenizer.c#L102-L104
+# https://github.com/python/typed_ast/blob/1.4.0/ast27/Parser/tokenizer.c#L102-L104
 TYPE_COMMENT_RE = re.compile(r'^#\s*type:\s*')
-# https://github.com/python/typed_ast/blob/55420396/ast27/Parser/tokenizer.c#L1400
-TYPE_IGNORE_RE = re.compile(TYPE_COMMENT_RE.pattern + r'ignore\s*(#|$)')
-# https://github.com/python/typed_ast/blob/55420396/ast27/Grammar/Grammar#L147
+# https://github.com/python/typed_ast/blob/1.4.0/ast27/Parser/tokenizer.c#L1408-L1413
+ASCII_NON_ALNUM = ''.join([chr(i) for i in range(128) if not chr(i).isalnum()])
+TYPE_IGNORE_RE = re.compile(TYPE_COMMENT_RE.pattern + r'ignore([{}]|$)'.format(ASCII_NON_ALNUM))
+# https://github.com/python/typed_ast/blob/1.4.0/ast27/Grammar/Grammar#L147
 TYPE_FUNC_RE = re.compile(r'^(\(.*?\))\s*->\s*(.*)$')
 
 
diff --git a/pyflakes/test/test_type_annotations.py b/pyflakes/test/test_type_annotations.py
index 9c34dcfd..3d5a4581 100644
--- a/pyflakes/test/test_type_annotations.py
+++ b/pyflakes/test/test_type_annotations.py
@@ -343,6 +343,26 @@ def test_typeCommentsAssignedToPreviousNode(self):
         # type: F
         """)
 
+    def test_typeIgnore(self):
+        self.flakes("""
+        a = 0  # type: ignore
+        b = 0  # type: ignore[excuse]
+        c = 0  # type: ignore=excuse
+        d = 0  # type: ignore [excuse]
+        e = 0  # type: ignore whatever
+        """)
+
+    def test_typeIgnoreBogus(self):
+        self.flakes("""
+        x = 1  # type: ignored
+        """, m.UndefinedName)
+
+    def test_typeIgnoreBogusUnicode(self):
+        error = m.CommentAnnotationSyntaxError if version_info < (3,) else m.UndefinedName
+        self.flakes("""
+        x = 2  # type: ignore\xc3
+        """, error)
+
     @skipIf(version_info < (3,), 'new in Python 3')
     def test_return_annotation_is_class_scope_variable(self):
         self.flakes("""