Keep distinct bracket types together when sole inner expression exceeds one line

[twosigmajab]

Current format:

frozenset(                                                                              
    {                                                                                                                                                                    
        0,                                                                              
        1,                                                                              
        2,                                                                              
        3,                                                                              
        ...,   # (continues in sequence, omitted for brevity)
        23,                                                                             
    }                                                                                   
)                                                                                       

Proposed format:

frozenset({                                                                              
    0,                                                                                   
    1,                                                                                   
    2,                                                                                   
    3,                                                                                   
    ...,                                                                                 
    23,                                                                                                                                                                  
})

This is a very common construct. The distinct bracket types provide enough differentiation between the inner and the outer expression; the extra level of indentation is just noise.

Looks tangentially-related: #177

[jab]

Also seems worth noting that in practice the expressions on each line are often longer than in this example (numbers from 0 to 23), so saving the extra level of indentation here can end up eliminating the need for the inner expressions to overflow into multiple lines, and other cascading effects that ultimately make it harder to read code that black is currently producing.

Is this an issue that a new contributor might be able to fix (potentially with some pointers on how to get started)? Thanks:)

[ichard26]

While this is older than #2071, I feel like it has more context so I'll be closing this in favour of that. I'll copy over the context provided here though.

Oh and thank you for the suggestion!