def visit_simple_stmt(self, node: Node) -> Iterator[Line]:
"""Visit a statement without nested statements."""
prev_type: Optional[int] = None
for child in node.children:
if (prev_type is None or prev_type == token.SEMI) and is_arith_like(child):
wrap_in_parentheses(node, child, visible=False)
prev_type = child.type
is_suite_like = node.parent and node.parent.type in STATEMENT
if is_suite_like:
if self.mode.is_pyi and is_stub_body(node):
yield from self.visit_default(node)
else:
yield from self.line(+1)
yield from self.visit_default(node)
yield from self.line(-1)
else:
if (
not self.mode.is_pyi
or not node.parent
or not is_stub_suite(node.parent)
):
yield from self.line()
yield from self.visit_default(node)
def remove_await_parens(node: Node) -> None:
if node.children[0].type == token.AWAIT and len(node.children) > 1:
if (
node.children[1].type == syms.atom
and node.children[1].children[0].type == token.LPAR
):
if maybe_make_parens_invisible_in_atom(
node.children[1],
parent=node,
remove_brackets_around_comma=True,
):
wrap_in_parentheses(node, node.children[1], visible=False)
# Since await is an expression we shouldn't remove
# brackets in cases where this would change
# the AST due to operator precedence.
# Therefore we only aim to remove brackets around
# power nodes that aren't also await expressions themselves.
# https://peps.python.org/pep-0492/#updated-operator-precedence-table
# N.B. We've still removed any redundant nested brackets though :)
opening_bracket = cast(Leaf, node.children[1].children[0])
closing_bracket = cast(Leaf, node.children[1].children[-1])
bracket_contents = cast(Node, node.children[1].children[1])
if bracket_contents.type != syms.power:
ensure_visible(opening_bracket)
ensure_visible(closing_bracket)
elif (
bracket_contents.type == syms.power
and bracket_contents.children[0].type == token.AWAIT
):
ensure_visible(opening_bracket)
ensure_visible(closing_bracket)
# If we are in a nested await then recurse down.
remove_await_parens(bracket_contents)
def visit_funcdef(self, node: Node) -> Iterator[Line]:
"""Visit function definition."""
if Preview.annotation_parens not in self.mode:
yield from self.visit_stmt(node, keywords={"def"}, parens=set())
else:
yield from self.line()
# Remove redundant brackets around return type annotation.
is_return_annotation = False
for child in node.children:
if child.type == token.RARROW:
is_return_annotation = True
elif is_return_annotation:
if child.type == syms.atom and child.children[0].type == token.LPAR:
if maybe_make_parens_invisible_in_atom(
child,
parent=node,
remove_brackets_around_comma=False,
):
wrap_in_parentheses(node, child, visible=False)
else:
wrap_in_parentheses(node, child, visible=False)
is_return_annotation = False
for child in node.children:
yield from self.visit(child)
def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
"""Make existing optional parentheses invisible or create new ones.
`parens_after` is a set of string leaf values immediately after which parens
should be put.
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):
if pc.value in FMT_OFF:
# This `node` has a prefix with `# fmt: off`, don't mess with parens.
return
check_lpar = False
for index, child in enumerate(list(node.children)):
# 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)
# Add parentheses around long tuple unpacking in assignments.
if (index == 0 and isinstance(child, Node)
and child.type == syms.testlist_star_expr):
check_lpar = True
if check_lpar:
if 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)
pass
elif node.type == syms.import_from:
# "import from" nodes store parentheses directly as part of
# the statement
if child.type == token.LPAR:
# make parentheses invisible
child.value = "" # type: ignore
node.children[-1].value = "" # type: ignore
elif child.type != token.STAR:
# insert invisible parentheses
node.insert_child(index, Leaf(token.LPAR, ""))
node.append_child(Leaf(token.RPAR, ""))
break
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
def visit_simple_stmt(self, node: Node) -> Iterator[Line]:
"""Visit a statement without nested statements."""
if first_child_is_arith(node):
wrap_in_parentheses(node, node.children[0], visible=False)
is_suite_like = node.parent and node.parent.type in STATEMENT
if is_suite_like:
if self.mode.is_pyi and is_stub_body(node):
yield from self.visit_default(node)
else:
yield from self.line(+1)
yield from self.visit_default(node)
yield from self.line(-1)
else:
if (not self.mode.is_pyi or not node.parent
or not is_stub_suite(node.parent)):
yield from self.line()
yield from self.visit_default(node)
def visit_power(self, node: Node) -> Iterator[Line]:
for idx, leaf in enumerate(node.children[:-1]):
next_leaf = node.children[idx + 1]
if not isinstance(leaf, Leaf):
continue
value = leaf.value.lower()
if (leaf.type == token.NUMBER and next_leaf.type == syms.trailer
# Ensure that we are in an attribute trailer
and next_leaf.children[0].type == token.DOT
# It shouldn't wrap hexadecimal, binary and octal literals
and not value.startswith(("0x", "0b", "0o"))
# It shouldn't wrap complex literals
and "j" not in value):
wrap_in_parentheses(node, leaf)
yield from self.visit_default(node)
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 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
should be put.
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, preview=preview):
if pc.value in FMT_OFF:
# This `node` has a prefix with `# fmt: off`, don't mess with parens.
return
check_lpar = False
for index, child in enumerate(list(node.children)):
# 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, preview=preview
)
# Add parentheses around long tuple unpacking in assignments.
if (
index == 0
and isinstance(child, Node)
and child.type == syms.testlist_star_expr
):
check_lpar = True
if check_lpar:
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)
elif node.type == syms.import_from:
# "import from" nodes store parentheses directly as part of
# the statement
if is_lpar_token(child):
assert is_rpar_token(node.children[-1])
# make parentheses invisible
child.value = ""
node.children[-1].value = ""
elif child.type != token.STAR:
# insert invisible parentheses
node.insert_child(index, Leaf(token.LPAR, ""))
node.append_child(Leaf(token.RPAR, ""))
break
elif (
index == 1
and child.type == token.STAR
and node.type == syms.except_clause
):
# In except* (PEP 654), the star is actually part of
# of the keyword. So we need to skip the insertion of
# invisible parentheses to work more precisely.
continue
elif not (isinstance(child, Leaf) and is_multiline_string(child)):
wrap_in_parentheses(node, child, visible=False)
comma_check = child.type == token.COMMA if preview else False
check_lpar = isinstance(child, Leaf) and (
child.value in parens_after or comma_check
)
