remove obviously unnecessary parentheses (#850)

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index 17aea7af264adafc4f5ee18cb9389cdfcdce8e17..694c1e961aa41bef489ea08145f1ee9faed7c69b 100644 (file)
--- a/black.py
+++ b/black.py
@@ -1602,6 +1602,26 @@ class LineGenerator(Visitor[Line]):
                 self.current_line.append(node)
         yield from super().visit_default(node)
 
+    def visit_atom(self, node: Node) -> Iterator[Line]:
+        # Always make parentheses invisible around a single node, because it should
+        # not be needed (except in the case of yield, where removing the parentheses
+        # produces a SyntaxError).
+        if (
+            len(node.children) == 3
+            and isinstance(node.children[0], Leaf)
+            and node.children[0].type == token.LPAR
+            and isinstance(node.children[2], Leaf)
+            and node.children[2].type == token.RPAR
+            and isinstance(node.children[1], Leaf)
+            and not (
+                node.children[1].type == token.NAME
+                and node.children[1].value == "yield"
+            )
+        ):
+            node.children[0].value = ""
+            node.children[2].value = ""
+        yield from super().visit_default(node)
+
     def visit_INDENT(self, node: Node) -> Iterator[Line]:
         """Increase indentation level, maybe yield a line."""
         # In blib2to3 INDENT never holds comments.