Acknowledge that ellipses are allowed in typing annotations (#2236)

Prevents false-positive bad-whitespace message

ChangeLog

@@ -352,6 +352,11 @@ Release date: |TBA|
       Close #2022
 
 
+    * Fix false-positive ``bad-whitespace`` message for typing annoatations
+    with ellipses in them
+
+      Close 1992
+
 What's New in Pylint 1.9?
 =========================
 

doc/whatsnew/2.0.rst

@@ -330,5 +330,8 @@ Other Changes
   this might actually cause bugs, so if you want to check for ``None`` values
   as well, pass ``--ignore-none=n`` to pylint.
 
+* Fix false-positive ``bad-whitespace`` message for typing annoatations
+  with ellipses in them
+
 
 .. _PEP 563: https://www.python.org/dev/peps/pep-0563/

pylint/checkers/format.py

@@ -682,7 +682,7 @@ def _has_valid_type_annotation(self, tokens, i):
             elif token[1] == ',':
                 if not bracket_level:
                     return False
-            elif token[1] == '.':
+            elif token[1] in ('.', '...'):
                 continue
             elif token[0] not in (tokenize.NAME, tokenize.STRING, tokenize.NL):
                 return False

pylint/test/unittest_checker_format.py

@@ -331,6 +331,13 @@ def testOperatorSpacingBad(self):
                     args=('Exactly one', 'required', 'around', 'comparison', 'a<  b\n ^'))):
             self.checker.process_tokens(_tokenize_str('a<  b\n'))
 
+    def testValidTypingAnnotationEllipses(self):
+        """Make sure ellipses in function typing annotation
+        doesn't cause a false positive bad-whitespace message"""
+        with self.assertNoMessages():
+            self.checker.process_tokens(
+                _tokenize_str('def foo(t: Tuple[str, ...] = None):\n'))
+
     def testEmptyLines(self):
         self.checker.config.no_space_check = []
         with self.assertAddsMessages(