Update FAQ: Mention formatting of custom jupyter cell magic (#2982)

[etc/vim.git] / src / black / linegen.py

diff --git a/src/black/linegen.py b/src/black/linegen.py
index 79475a83f0e363c5f9f223278c5a3ebdf5f7fad6..2cf9cf3130a998273c0de6055775a3f5e13dc627 100644 (file)
--- 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 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
 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


@@ -313,8 +318,14 @@ class LineGenerator(Visitor[Line]):
         self.visit_try_stmt = partial(
             v, keywords={"try", "except", "else", "finally"}, parens=Ø
         )
         self.visit_try_stmt = partial(
             v, keywords={"try", "except", "else", "finally"}, parens=Ø
         )

-        self.visit_except_clause = partial(v, keywords={"except"}, parens=Ø)
-        self.visit_with_stmt = partial(v, keywords={"with"}, parens=Ø)
+        if self.mode.preview:
+            self.visit_except_clause = partial(
+                v, keywords={"except"}, parens={"except"}
+            )
+            self.visit_with_stmt = partial(v, keywords={"with"}, parens={"with"})
+        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)
         self.visit_expr_stmt = partial(v, keywords=Ø, parens=ASSIGNMENTS)
         self.visit_funcdef = partial(v, keywords={"def"}, parens=Ø)
         self.visit_classdef = partial(v, keywords={"class"}, parens=Ø)
         self.visit_expr_stmt = partial(v, keywords=Ø, parens=ASSIGNMENTS)


@@ -665,9 +676,9 @@ def dont_increase_indentation(split_func: Transformer) -> Transformer:
 
     @wraps(split_func)
     def split_wrapper(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]:
 
     @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
 
 
     return split_wrapper
 


@@ -835,8 +846,27 @@ def normalize_invisible_parens(
             check_lpar = True
 
         if check_lpar:
             check_lpar = True
 
         if check_lpar:

-            if child.type == syms.atom:
-                if maybe_make_parens_invisible_in_atom(child, parent=node):
+            if (
+                preview
+                and child.type == syms.atom
+                and node.type == syms.for_stmt
+                and isinstance(child.prev_sibling, Leaf)
+                and child.prev_sibling.type == token.NAME
+                and child.prev_sibling.value == "for"
+            ):
+                if maybe_make_parens_invisible_in_atom(
+                    child,
+                    parent=node,
+                    remove_brackets_around_comma=True,
+                ):
+                    wrap_in_parentheses(node, child, visible=False)
+            elif preview and isinstance(child, Node) and node.type == syms.with_stmt:
+                remove_with_parens(child, node)
+            elif child.type == syms.atom:
+                if maybe_make_parens_invisible_in_atom(
+                    child,
+                    parent=node,
+                ):

                     wrap_in_parentheses(node, child, visible=False)
             elif is_one_tuple(child):
                 wrap_in_parentheses(node, child, visible=True)
                     wrap_in_parentheses(node, child, visible=False)
             elif is_one_tuple(child):
                 wrap_in_parentheses(node, child, visible=True)


@@ -857,24 +887,78 @@ def normalize_invisible_parens(
             elif not (isinstance(child, Leaf) and is_multiline_string(child)):
                 wrap_in_parentheses(node, child, visible=False)
 
             elif not (isinstance(child, Leaf) and is_multiline_string(child)):
                 wrap_in_parentheses(node, child, visible=False)
 

-        check_lpar = isinstance(child, Leaf) and child.value in parens_after
+        comma_check = child.type == token.COMMA if preview else False

 
 

+        check_lpar = isinstance(child, Leaf) and (
+            child.value in parens_after or comma_check
+        )

 
 

-def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool:
+
+def remove_with_parens(node: Node, parent: Node) -> None:
+    """Recursively hide optional parens in `with` statements."""
+    # Removing all unnecessary parentheses in with statements in one pass is a tad
+    # complex as different variations of bracketed statements result in pretty
+    # different parse trees:
+    #
+    # with (open("file")) as f:                       # this is an asexpr_test
+    #     ...
+    #
+    # with (open("file") as f):                       # this is an atom containing an
+    #     ...                                         # asexpr_test
+    #
+    # with (open("file")) as f, (open("file")) as f:  # this is asexpr_test, COMMA,
+    #     ...                                         # asexpr_test
+    #
+    # with (open("file") as f, open("file") as f):    # an atom containing a
+    #     ...                                         # testlist_gexp which then
+    #                                                 # contains multiple asexpr_test(s)
+    if node.type == syms.atom:
+        if maybe_make_parens_invisible_in_atom(
+            node,
+            parent=parent,
+            remove_brackets_around_comma=True,
+        ):
+            wrap_in_parentheses(parent, node, visible=False)
+        if isinstance(node.children[1], Node):
+            remove_with_parens(node.children[1], node)
+    elif node.type == syms.testlist_gexp:
+        for child in node.children:
+            if isinstance(child, Node):
+                remove_with_parens(child, node)
+    elif node.type == syms.asexpr_test and not any(
+        leaf.type == token.COLONEQUAL for leaf in node.leaves()
+    ):
+        if maybe_make_parens_invisible_in_atom(
+            node.children[0],
+            parent=node,
+            remove_brackets_around_comma=True,
+        ):
+            wrap_in_parentheses(node, node.children[0], visible=False)
+
+
+def maybe_make_parens_invisible_in_atom(
+    node: LN,
+    parent: LN,
+    remove_brackets_around_comma: 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.
 
     Returns whether the node should itself be wrapped in invisible parentheses.
     """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.
 
     Returns whether the node should itself be wrapped in invisible parentheses.

-

     """
     """

-

     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)
     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 (
+            # This condition tries to prevent removing non-optional brackets
+            # around a tuple, however, can be a bit overzealous so we provide
+            # and option to skip this check for `for` and `with` statements.
+            not remove_brackets_around_comma
+            and max_delimiter_priority_in_atom(node) >= COMMA_PRIORITY
+        )

     ):
         return False
 
     ):
         return False
 


@@ -897,7 +981,11 @@ def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool:
         # make parentheses invisible
         first.value = ""
         last.value = ""
         # 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,
+            remove_brackets_around_comma=remove_brackets_around_comma,
+        )

 
         if is_atom_with_invisible_parens(middle):
             # Strip the invisible parens from `middle` by replacing
 
         if is_atom_with_invisible_parens(middle):
             # Strip the invisible parens from `middle` by replacing


@@ -973,7 +1061,7 @@ 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
                     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
                     )
                 ):
                         leaf.opening_bracket, leaf, line.leaves
                     )
                 ):


@@ -1001,7 +1089,7 @@ 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
                 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.
             ):
                 # Never omit bracket pairs with trailing commas.
                 # We need to explode on those.