SPLIT_ALL[_TOP_LEVEL]_COMMA_SEPARATED_VALUES breaks on tuple unpacking

[alexey-pelykh]

values = [
  ('a', '1'),
  ('b', '2'),
]
values = [
  really_quite_long_function(some_quite_long_arg, value)
  for some_quite_long_arg, value in values
]

with SPLIT_ALL_COMMA_SEPARATED_VALUES enabled being reformatted to

values = [
    ('a',
     '1'),
    ('b',
     '2'),
]
values = [
    really_quite_long_function(some_quite_long_arg,
                               value) for some_quite_long_arg,
    value in values
]

and with SPLIT_ALL_TOP_LEVEL_COMMA_SEPARATED_VALUES enabled being reformatted to

values = [
    ('a', '1'),
    ('b', '2'),
]
values = [
    really_quite_long_function(some_quite_long_arg, value)
    for some_quite_long_arg,
    value in values
]

while replacing

  for some_quite_long_arg, value in values

with

  for (some_quite_long_arg, value) in values

yields to a different result.

Is this an intended behavior?

[bwendling]

I don't think this is intended behavior. The for part shouldn't split like that, even with these flags.