Don't enforce a split before a comment after a container opening.

CHANGELOG

@@ -13,6 +13,8 @@
 - When calculating the split penalty for a "trailer", process the child nodes
   afterwards because their penalties may change. For example if a list
   comprehension is an argument.
+- Don't enforce a split before a comment after the opening of a container if it
+  doesn't it on the current line. We try hard not to move such comments around.
 
 ## [0.19.0] 2017-10-14
 ### Added

yapf/yapflib/format_decision_state.py

@@ -408,16 +408,15 @@ def SurroundedByParens(token):
         return True
 
     if (previous.OpensScope() and not current.OpensScope() and
+        not current.is_comment and
         format_token.Subtype.SUBSCRIPT_BRACKET not in previous.subtypes):
-      if not current.is_comment:
-        if pprevious and not pprevious.is_keyword and not pprevious.is_name:
-          # We want to split if there's a comment in the container.
-          token = current
-          while token != previous.matching_bracket:
-            if token.is_comment:
-              return True
-            token = token.next_token
-
+      if pprevious and not pprevious.is_keyword and not pprevious.is_name:
+        # We want to split if there's a comment in the container.
+        token = current
+        while token != previous.matching_bracket:
+          if token.is_comment:
+            return True
+          token = token.next_token
       if previous.value == '(':
         pptoken = previous.previous_token
         if not pptoken or not pptoken.is_name:
@@ -431,7 +430,7 @@ def SurroundedByParens(token):
             return current.next_token != previous.matching_bracket
       else:
         # Split after the opening of a container if it doesn't fit on the
-        # current line or if it has a comment.
+        # current line.
         if not self._FitsOnLine(previous, previous.matching_bracket):
           return True
 
@@ -756,6 +755,7 @@ def ImplicitStringConcatenation(tok):
     return length + self.stack[-2].indent <= self.column_limit
 
   def _ArgumentListHasDictionaryEntry(self, token):
+    """Check if the function argument list has a dictionary as an arg."""
     if _IsArgumentToFunction(token):
       while token:
         if token.value == '{':

yapftests/reformatter_buganizer_test.py

@@ -28,6 +28,38 @@ class BuganizerFixes(yapf_test_helper.YAPFTest):
   def setUpClass(cls):
     style.SetGlobalStyle(style.CreateChromiumStyle())
 
+  def testB66011084(self):
+    unformatted_code = """\
+X = {
+"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa":  # Comment 1.
+([] if True else [ # Comment 2.
+    "bbbbbbbbbbbbbbbbbbb",  # Comment 3.
+    "cccccccccccccccccccccccc", # Comment 4.
+    "ddddddddddddddddddddddddd", # Comment 5.
+    "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeee", # Comment 6.
+    "fffffffffffffffffffffffffffffff", # Comment 7.
+    "ggggggggggggggggggggggggggg", # Comment 8.
+    "hhhhhhhhhhhhhhhhhh",  # Comment 9.
+]),
+}
+"""
+    expected_formatted_code = """\
+X = {
+    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa":  # Comment 1.
+        ([] if True else [  # Comment 2.
+            "bbbbbbbbbbbbbbbbbbb",  # Comment 3.
+            "cccccccccccccccccccccccc",  # Comment 4.
+            "ddddddddddddddddddddddddd",  # Comment 5.
+            "eeeeeeeeeeeeeeeeeeeeeeeeeeeeeee",  # Comment 6.
+            "fffffffffffffffffffffffffffffff",  # Comment 7.
+            "ggggggggggggggggggggggggggg",  # Comment 8.
+            "hhhhhhhhhhhhhhhhhh",  # Comment 9.
+        ]),
+}
+"""
+    uwlines = yapf_test_helper.ParseAndUnwrap(unformatted_code)
+    self.assertCodeEqual(expected_formatted_code, reformatter.Reformat(uwlines))
+
   def testB67455376(self):
     unformatted_code = """\
 sponge_ids.extend(invocation.id() for invocation in self._client.GetInvocationsByLabels(labels))
@@ -1292,15 +1324,14 @@ def testB19194420(self):
     self.assertCodeEqual(code, reformatter.Reformat(uwlines))
 
   def testB19073499(self):
-    code = textwrap.dedent("""\
-        instance = (
-            aaaaaaa.bbbbbbb().ccccccccccccccccc().ddddddddddd({
-                'aa': 'context!'
-            }).eeeeeeeeeeeeeeeeeee(
-                {  # Inline comment about why fnord has the value 6.
-                    'fnord': 6
-                }))
-        """)
+    code = """\
+instance = (
+    aaaaaaa.bbbbbbb().ccccccccccccccccc().ddddddddddd({
+        'aa': 'context!'
+    }).eeeeeeeeeeeeeeeeeee({  # Inline comment about why fnord has the value 6.
+        'fnord': 6
+    }))
+"""
     uwlines = yapf_test_helper.ParseAndUnwrap(code)
     self.assertCodeEqual(code, reformatter.Reformat(uwlines))