nixfmt incorrectly transforms strings to double single quote form

[florpe]

Description

Nixfmt (sometimes?) converts strings to double single quote form. For certain strings, the transformation is incorrect. No transformation at all would be preferrable.

Small example input

  someValue = ",\n    ";

Expected output

  someValue = ",\n    "; # Unchanged, no transformation necessary

Actual output

  someValue = ''
    ,
        ''; # Equivalent to "\n,"

[parenthetical]

The conversion to multiline strings is something that's been very ergonomic for my team, so we'd be sad to lose it. A length heuristic might help?

That said, here's another incorrect transformation.

Sample input

"\n'"

Expected output

''

''\'''

Actual output

''

  '''

The output doesn't parse anymore.

[parenthetical]

Edit: it seems like this one is fixed in 0.5.0!

Another case:

Sample input

"'\${x:y}'\n"

Expected output

''
  ''\'''${x:y}'
''

Actual output

''
  '''${x:y}'
''

[yorickvP]

Yep! Fixed in v0.5.0!