def _fix_extraneous_parens(tokens: List[Token], i: int) -> None:
# search forward for another non-coding token
i += 1
while tokens[i].name in NON_CODING_TOKENS:
i += 1
# if we did not find another brace, return immediately
if tokens[i].src != '(':
return
start = i
depth = 1
while depth:
i += 1
# found comma or yield at depth 1: this is a tuple / coroutine
if depth == 1 and tokens[i].src in {',', 'yield'}:
return
elif tokens[i].src in OPENING:
depth += 1
elif tokens[i].src in CLOSING:
depth -= 1
end = i
# empty tuple
if all(t.name in NON_CODING_TOKENS for t in tokens[start + 1:i]):
return
# search forward for the next non-coding token
i += 1
while tokens[i].name in NON_CODING_TOKENS:
i += 1
if tokens[i].src == ')':
remove_brace(tokens, end)
remove_brace(tokens, start)
def _fix_set_literal(i: int, tokens: List[Token], *, arg: ast.expr) -> None:
# TODO: this could be implemented with a little extra logic
if not immediately_paren('set', tokens, i):
return
gen = isinstance(arg, ast.GeneratorExp)
set_victims = victims(tokens, i + 1, arg, gen=gen)
del set_victims.starts[0]
end_index = set_victims.ends.pop()
tokens[end_index] = Token('OP', '}')
for index in reversed(set_victims.starts + set_victims.ends):
remove_brace(tokens, index)
tokens[i:i + 2] = [Token('OP', '{')]
def _fix_dict_comp(
i: int,
tokens: List[Token],
arg: Union[ast.ListComp, ast.GeneratorExp],
) -> None:
if not immediately_paren('dict', tokens, i):
return
dict_victims = victims(tokens, i + 1, arg, gen=True)
elt_victims = victims(tokens, dict_victims.arg_index, arg.elt, gen=True)
del dict_victims.starts[0]
end_index = dict_victims.ends.pop()
tokens[end_index] = Token('OP', '}')
for index in reversed(dict_victims.ends):
remove_brace(tokens, index)
# See #6, Fix SyntaxError from rewriting dict((a, b)for a, b in y)
if tokens[elt_victims.ends[-1] + 1].src == 'for':
tokens.insert(elt_victims.ends[-1] + 1, Token(UNIMPORTANT_WS, ' '))
for index in reversed(elt_victims.ends):
remove_brace(tokens, index)
assert elt_victims.first_comma_index is not None
tokens[elt_victims.first_comma_index] = Token('OP', ':')
for index in reversed(dict_victims.starts + elt_victims.starts):
remove_brace(tokens, index)
tokens[i:i + 2] = [Token('OP', '{')]
def _fix_percent_format_tuple(
i: int,
tokens: List[Token],
*,
node_right: ast.Tuple,
) -> None:
# TODO: handle \N escape sequences
if r'\N' in tokens[i].src:
return
# TODO: this is overly timid
paren = i + 4
if tokens_to_src(tokens[i + 1:paren + 1]) != ' % (':
return
fmt_victims = victims(tokens, paren, node_right, gen=False)
fmt_victims.ends.pop()
for index in reversed(fmt_victims.starts + fmt_victims.ends):
remove_brace(tokens, index)
newsrc = _percent_to_format(tokens[i].src)
tokens[i] = tokens[i]._replace(src=newsrc)
tokens[i + 1:paren] = [Token('Format', '.format'), Token('OP', '(')]