Black: # fmt: pass - ignore formatting for single statements

[mrgnw]

Feature request:
# fmt: pass would skip formatting for the single statement that immediately follows.

Is your feature request related to a problem? Please describe.

Not a response to a problem but it might be helpful for the following reasons:

• Easier to use / less typing
• Can't forget to turn it back on
  
  
  
  • Or accidentally insert code you do want formatted into an unformatted block
  
  
• Encourages ignoring less code
  
  
  
  • One-offs are always isolated to one statement instead of potentially large chunks of code.
  
  

Describe the solution you'd like

z = "hello " + "world"

# fmt: pass
custom_formatting = [
    0,  1,  2,
    3,  4,  5,
    6,  7,  8,
]

regular_formatting = [
   0,  1,  2,  'this will be formatted'
]

The custom_formatting list would be ignored, everything else would be formatted.

Describe alternatives you've considered

1. Current solution

# fmt: off
ugly_code=('but I want it this way')
even_more=('dont\'t judge me')
# fmt: on

1. #fmt: off at end of line (#790)
   I believe # fmt: pass addresses the same concern while also being a bit more flexible.
   
   
   
   • a single statement could be multi-line
   
   
   • a long line would bury an inline comment
   
   
   • # fmt: pass is more readable & predictable as a separate line
   
   
2. Disable formatting for certain expressions only. #798
3. Deal with it

Additional context

Naming:

• # fmt: pass reflects Python's existing pass statement. Hopefully this hints that you can use it to temporarily appease the formatter for one quick thing, but it's not something you want everywhere.

• Naming could be anything, e.g. "pass", "skip", "ignore"

[vitalik]

I like this one..

but would like to extend it a bit more

foo = bar.<100 characters +> # fmt: pass

if i place at the end of the statement - it should work as well (not only before the statement)

[saroad2]

I would love to see this feature merged!

[rbarrette]

I like this one..

but would like to extend it a bit more

foo = bar.<100 characters +> # fmt: pass

if i place at the end of the statement - it should work as well (not only before the statement)

Expanding on @vitalik's ask. It would be great if this feature would be compatible with other inline comment options.

def example(self): #noqa - squelch some lint check # fmt: pass

[prashanth-sams]

The reason why I uninstalled black :(

[clragon]

We definitly need something like this.

I have ansible vars in my python script
which require me to write something like
{{ variable_name }} which black will turn into {{variable_name}}
which afaik isnt valid anymore.

turning the line into

# fmt: off
my_var = {{ variable_name }}
# fmt: on

looks very ugly in my opinion.
this however:
my_var = {{ variable_name }} # fmt: skip
would look quite okay.