line_length=1 to reduce churn (#1092)

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index 24ab6607f7bf61b22b8e325ed6e94a2e71bcaf48..00de8d23245e92cc4ee42a9d83c3eda004f54e40 100644 (file)
--- a/black.py
+++ b/black.py
@@ -1717,19 +1717,6 @@ class LineGenerator(Visitor[Line]):
                 self.current_line.append(node)
         yield from super().visit_default(node)
 
-    def visit_factor(self, node: Node) -> Iterator[Line]:
-        """Force parentheses between a unary op and a binary power:
-
-        -2 ** 8 -> -(2 ** 8)
-        """
-        child = node.children[1]
-        if child.type == syms.power and len(child.children) == 3:
-            lpar = Leaf(token.LPAR, "(")
-            rpar = Leaf(token.RPAR, ")")
-            index = child.remove() or 0
-            node.insert_child(index, Node(syms.atom, [lpar, child, rpar]))
-        yield from self.visit_default(node)
-
     def visit_INDENT(self, node: Node) -> Iterator[Line]:
         """Increase indentation level, maybe yield a line."""
         # In blib2to3 INDENT never holds comments.
@@ -1829,6 +1816,23 @@ class LineGenerator(Visitor[Line]):
             yield from self.line()
         yield from self.visit_default(leaf)
 
+    def visit_factor(self, node: Node) -> Iterator[Line]:
+        """Force parentheses between a unary op and a binary power:
+
+        -2 ** 8 -> -(2 ** 8)
+        """
+        _operator, operand = node.children
+        if (
+            operand.type == syms.power
+            and len(operand.children) == 3
+            and operand.children[1].type == token.DOUBLESTAR
+        ):
+            lpar = Leaf(token.LPAR, "(")
+            rpar = Leaf(token.RPAR, ")")
+            index = operand.remove() or 0
+            node.insert_child(index, Node(syms.atom, [lpar, operand, rpar]))
+        yield from self.visit_default(node)
+
     def __attrs_post_init__(self) -> None:
         """You are in a twisty little maze of passages."""
         v = self.visit_stmt
@@ -2402,7 +2406,9 @@ def split_line(
             # All splits failed, best effort split with no omits.
             # This mostly happens to multiline strings that are by definition
             # reported as not fitting a single line.
-            yield from right_hand_split(line, line_length, features=features)
+            # line_length=1 is silly, but somehow produces better formatting
+            # than other things we've tried so far. See #762 and #781.
+            yield from right_hand_split(line, line_length=1, features=features)
 
         if line.inside_brackets:
             split_funcs = [delimiter_split, standalone_comment_split, rhs]
@@ -2601,9 +2607,11 @@ def bracket_split_build_line(
             # Since body is a new indent level, remove spurious leading whitespace.
             normalize_prefix(leaves[0], inside_brackets=True)
             # Ensure a trailing comma for imports and standalone function arguments, but
-            # be careful not to add one after any comments.
-            no_commas = original.is_def and not any(
-                l.type == token.COMMA for l in leaves
+            # be careful not to add one after any comments or within type annotations.
+            no_commas = (
+                original.is_def
+                and opening_bracket.value == "("
+                and not any(l.type == token.COMMA for l in leaves)
             )
 
             if original.is_import or no_commas:
@@ -3491,6 +3499,9 @@ def gen_python_files_in_dir(
         # Then ignore with `exclude` option.
         try:
             normalized_path = "/" + child.resolve().relative_to(root).as_posix()
+        except OSError as e:
+            report.path_ignored(child, f"cannot be read because {e}")
+            continue
         except ValueError:
             if child.is_symlink():
                 report.path_ignored(
@@ -3775,8 +3786,10 @@ def dump_to_file(*output: str) -> str:
 
 @contextmanager
 def nullcontext() -> Iterator[None]:
-    """Return context manager that does nothing.
-    Similar to `nullcontext` from python 3.7"""
+    """Return an empty context manager.
+
+    To be used like `nullcontext` in Python 3.7.
+    """
     yield