Removing empty parentheses after class name (#180)

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index f235afe60c7aa3545a16fd96c0e8d7a9459fa72b..cfb5028d68d85be324c450838f7797ecbe22e5fd 100644 (file)
--- a/black.py
+++ b/black.py
@@ -743,6 +743,9 @@ class Line:
         if not has_value:
             return
 
+        if token.COLON == leaf.type and self.is_class_parenth_empty:
+            del self.leaves[-2:]
+
         if self.leaves and not preformatted:
             # Note: at this point leaf.prefix should be empty except for
             # imports, for which we only preserve newlines.
@@ -840,6 +843,19 @@ class Line:
             and self.leaves[0].value == "yield"
         )
 
+    @property
+    def is_class_parenth_empty(self) -> bool:
+        """Is this class parentheses blank?"""
+        return (
+            bool(self)
+            and len(self.leaves) == 4
+            and self.is_class
+            and self.leaves[2].type == token.LPAR
+            and self.leaves[2].value == "("
+            and self.leaves[3].type == token.RPAR
+            and self.leaves[3].value == ")"
+        )
+
     def contains_standalone_comments(self, depth_limit: int = sys.maxsize) -> bool:
         """If so, needs to be split before emitting."""
         for leaf in self.leaves:
@@ -1125,6 +1141,7 @@ class LineGenerator(Visitor[Line]):
 
         If any lines were generated, set up a new current_line.
         """
+
         if not self.current_line:
             if self.current_line.__class__ == type:
                 self.current_line.depth += indent