Formatting nits

black.py

@@ -743,9 +743,8 @@ def append(self, leaf: Leaf, preformatted: bool = False) -> None:
         if not has_value:
             return
 
-        if token.COLON == leaf.type and self.is_class_parenth_empty:
+        if token.COLON == leaf.type and self.is_class_paren_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.
@@ -755,7 +754,6 @@ def append(self, leaf: Leaf, preformatted: bool = False) -> None:
         if self.inside_brackets or not preformatted:
             self.bracket_tracker.mark(leaf)
             self.maybe_remove_trailing_comma(leaf)
-
         if not self.append_comment(leaf):
             self.leaves.append(leaf)
 
@@ -844,8 +842,11 @@ def is_yield(self) -> bool:
         )
 
     @property
-    def is_class_parenth_empty(self) -> bool:
-        """Is this class parentheses blank?"""
+    def is_class_paren_empty(self) -> bool:
+        """Is this a class with no base classes but using parentheses?
+
+        Those are unnecessary and should be removed.
+        """
         return (
             bool(self)
             and len(self.leaves) == 4
@@ -1141,7 +1142,6 @@ def line(self, indent: int = 0, type: Type[Line] = Line) -> Iterator[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

tests/class_blank_parentheses.py

@@ -1,15 +1,10 @@
 class SimpleClassWithBlankParentheses():
     pass
-
-
-class ClassWithSpaceParentheses():
+class ClassWithSpaceParentheses ( ):
     first_test_data = 90
     second_test_data = 100
-
     def test_func(self):
         return None
-
-
 class ClassWithEmptyFunc(object):
 
     def func_with_blank_parentheses():
@@ -18,16 +13,11 @@ def func_with_blank_parentheses():
 
 def public_func_with_blank_parentheses():
     return None
-
-
 def class_under_the_func_with_blank_parentheses():
-
     class InsideFunc():
         pass
-
-
-class NormalClass():
-
+class NormalClass (
+):
     def func_for_testing(self, first, second):
         sum = first + second
         return sum