X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/a24e1f795975350f7b1d8898d831916a9f6dbc6a..ac7402cbf6a0deb5c74e9abcffc5bd7b1148fda5:/src/black/linegen.py

diff --git a/src/black/linegen.py b/src/black/linegen.py
index 4dc242a..8a28c39 100644
--- a/src/black/linegen.py
+++ b/src/black/linegen.py
@@ -8,7 +8,12 @@ from typing import Collection, Iterator, List, Optional, Set, Union
 from black.nodes import WHITESPACE, RARROW, STATEMENT, STANDALONE_COMMENT
 from black.nodes import ASSIGNMENTS, OPENING_BRACKETS, CLOSING_BRACKETS
 from black.nodes import Visitor, syms, is_arith_like, ensure_visible
-from black.nodes import is_docstring, is_empty_tuple, is_one_tuple, is_one_tuple_between
+from black.nodes import (
+    is_docstring,
+    is_empty_tuple,
+    is_one_tuple,
+    is_one_sequence_between,
+)
 from black.nodes import is_name_token, is_lpar_token, is_rpar_token
 from black.nodes import is_walrus_assignment, is_yield, is_vararg, is_multiline_string
 from black.nodes import is_stub_suite, is_stub_body, is_atom_with_invisible_parens
@@ -72,7 +77,7 @@ class LineGenerator(Visitor[Line]):
         """Default `visit_*()` implementation. Recurses to children of `node`."""
         if isinstance(node, Leaf):
             any_open_brackets = self.current_line.bracket_tracker.any_open_brackets()
-            for comment in generate_comments(node):
+            for comment in generate_comments(node, preview=self.mode.preview):
                 if any_open_brackets:
                     # any comment within brackets is subject to splitting
                     self.current_line.append(comment)
@@ -132,7 +137,7 @@ class LineGenerator(Visitor[Line]):
         `parens` holds a set of string leaf values immediately after which
         invisible parens should be put.
         """
-        normalize_invisible_parens(node, parens_after=parens)
+        normalize_invisible_parens(node, parens_after=parens, preview=self.mode.preview)
         for child in node.children:
             if is_name_token(child) and child.value in keywords:
                 yield from self.line()
@@ -141,7 +146,7 @@ class LineGenerator(Visitor[Line]):
 
     def visit_match_case(self, node: Node) -> Iterator[Line]:
         """Visit either a match or case statement."""
-        normalize_invisible_parens(node, parens_after=set())
+        normalize_invisible_parens(node, parens_after=set(), preview=self.mode.preview)
 
         yield from self.line()
         for child in node.children:
@@ -313,7 +318,12 @@ class LineGenerator(Visitor[Line]):
         self.visit_try_stmt = partial(
             v, keywords={"try", "except", "else", "finally"}, parens=Ø
         )
-        self.visit_except_clause = partial(v, keywords={"except"}, parens=Ø)
+        if self.mode.preview:
+            self.visit_except_clause = partial(
+                v, keywords={"except"}, parens={"except"}
+            )
+        else:
+            self.visit_except_clause = partial(v, keywords={"except"}, parens=Ø)
         self.visit_with_stmt = partial(v, keywords={"with"}, parens=Ø)
         self.visit_funcdef = partial(v, keywords={"def"}, parens=Ø)
         self.visit_classdef = partial(v, keywords={"class"}, parens=Ø)
@@ -665,9 +675,9 @@ def dont_increase_indentation(split_func: Transformer) -> Transformer:
 
     @wraps(split_func)
     def split_wrapper(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]:
-        for line in split_func(line, features):
-            normalize_prefix(line.leaves[0], inside_brackets=True)
-            yield line
+        for split_line in split_func(line, features):
+            normalize_prefix(split_line.leaves[0], inside_brackets=True)
+            yield split_line
 
     return split_wrapper
 
@@ -802,7 +812,9 @@ def normalize_prefix(leaf: Leaf, *, inside_brackets: bool) -> None:
     leaf.prefix = ""
 
 
-def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
+def normalize_invisible_parens(
+    node: Node, parens_after: Set[str], *, preview: bool
+) -> None:
     """Make existing optional parentheses invisible or create new ones.
 
     `parens_after` is a set of string leaf values immediately after which parens
@@ -811,7 +823,7 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
     Standardizes on visible parentheses for single-element tuples, and keeps
     existing visible parentheses for other tuples and generator expressions.
     """
-    for pc in list_comments(node.prefix, is_endmarker=False):
+    for pc in list_comments(node.prefix, is_endmarker=False, preview=preview):
         if pc.value in FMT_OFF:
             # This `node` has a prefix with `# fmt: off`, don't mess with parens.
             return
@@ -820,7 +832,9 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
         # Fixes a bug where invisible parens are not properly stripped from
         # assignment statements that contain type annotations.
         if isinstance(child, Node) and child.type == syms.annassign:
-            normalize_invisible_parens(child, parens_after=parens_after)
+            normalize_invisible_parens(
+                child, parens_after=parens_after, preview=preview
+            )
 
         # Add parentheses around long tuple unpacking in assignments.
         if (
@@ -832,7 +846,11 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
 
         if check_lpar:
             if child.type == syms.atom:
-                if maybe_make_parens_invisible_in_atom(child, parent=node):
+                if maybe_make_parens_invisible_in_atom(
+                    child,
+                    parent=node,
+                    preview=preview,
+                ):
                     wrap_in_parentheses(node, child, visible=False)
             elif is_one_tuple(child):
                 wrap_in_parentheses(node, child, visible=True)
@@ -856,7 +874,11 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
         check_lpar = isinstance(child, Leaf) and child.value in parens_after
 
 
-def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool:
+def maybe_make_parens_invisible_in_atom(
+    node: LN,
+    parent: LN,
+    preview: bool = False,
+) -> bool:
     """If it's safe, make the parens in the atom `node` invisible, recursively.
     Additionally, remove repeated, adjacent invisible parens from the atom `node`
     as they are redundant.
@@ -864,13 +886,23 @@ def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool:
     Returns whether the node should itself be wrapped in invisible parentheses.
 
     """
+    if (
+        preview
+        and parent.type == syms.for_stmt
+        and isinstance(node.prev_sibling, Leaf)
+        and node.prev_sibling.type == token.NAME
+        and node.prev_sibling.value == "for"
+    ):
+        for_stmt_check = False
+    else:
+        for_stmt_check = True
 
     if (
         node.type != syms.atom
         or is_empty_tuple(node)
         or is_one_tuple(node)
         or (is_yield(node) and parent.type != syms.expr_stmt)
-        or max_delimiter_priority_in_atom(node) >= COMMA_PRIORITY
+        or (max_delimiter_priority_in_atom(node) >= COMMA_PRIORITY and for_stmt_check)
     ):
         return False
 
@@ -893,7 +925,7 @@ def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool:
         # make parentheses invisible
         first.value = ""
         last.value = ""
-        maybe_make_parens_invisible_in_atom(middle, parent=parent)
+        maybe_make_parens_invisible_in_atom(middle, parent=parent, preview=preview)
 
         if is_atom_with_invisible_parens(middle):
             # Strip the invisible parens from `middle` by replacing
@@ -969,7 +1001,7 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[Set[Leaf
                     prev
                     and prev.type == token.COMMA
                     and leaf.opening_bracket is not None
-                    and not is_one_tuple_between(
+                    and not is_one_sequence_between(
                         leaf.opening_bracket, leaf, line.leaves
                     )
                 ):
@@ -997,7 +1029,7 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[Set[Leaf
                 prev
                 and prev.type == token.COMMA
                 and leaf.opening_bracket is not None
-                and not is_one_tuple_between(leaf.opening_bracket, leaf, line.leaves)
+                and not is_one_sequence_between(leaf.opening_bracket, leaf, line.leaves)
             ):
                 # Never omit bracket pairs with trailing commas.
                 # We need to explode on those.