in windows, xargs.py too large command line

[ufwtlsb]

I use pre-commit to check java in windows
pre-commit run -a

get
The command line is too long.

I find xargs.py _get_platform_max_length too large size

I change it ,then can run

def _get_platform_max_length() -> int:  # pragma: no cover (platform specific)
    if os.name == 'posix':
        maximum = os.sysconf('SC_ARG_MAX') - 2048 - _environ_size()
        maximum = max(min(maximum, 2 ** 17), 2 ** 12)
        return maximum
    elif os.name == 'nt':
        return 2 ** 13 - 2048  # UNICODE_STRING max - headroom
    else:
        # posix minimum
        return 2 ** 12

[asottile]

can you share your config and output and log? that value has been pretty thoroughly tested -- my guess is some underlying tool is expanding furthur in an incorrect way but I can't tell without you showing me anything

[ufwtlsb]

i use https://github.com/macisamuele/language-formatters-pre-commit-hooks and report error

[asottile]

no no, show me your configuration, the command you ran, the output you get from that command, and the error log pre-commit generates

[ufwtlsb]

myconfig：

  - repo: https://github.com/macisamuele/language-formatters-pre-commit-hooks.git
    rev: master
    hooks:
      - id: pretty-format-java

run：
pre-commit run -a

have many java， so error message

命令行太长
mean: too command line long

[asottile]

can you show the full outout please. show the whole thing I don't particularly care if it is not english

[apietrzak]

Hello @asottile, I have pretty the same issue:

Check for merge conflicts................................................Passed
prettier.................................................................Failed
- hook id: prettier                                                            
- duration: 7.17s                                                              
- exit code: 2                                                                 
- files were modified by this hook                                             
                                                                               
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                                  
The command line is too long.                                  

It was executed on Windows 10, python 3.9 and pre-commit 2.8.2

[asottile]

do you have a repository to link to?

that's prettier giving that result and not python, python's error looks like: [WinError 206] The filename or extension is too long (so it's probably prettier's fault)

[apietrzak]

@asottile I can send only a config of pre-commit:

repos:
-   repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v2.5.0
    hooks:
    -   id: check-merge-conflict
- repo: https://github.com/prettier/pre-commit
  rev: v2.1.2
  hooks:
    - id: prettier
      files: ^src_frontend/

Based on my invastigation there is an issue with executing a command to run the prettier hook.
He's trying to execute: .cache\pre-commit\repodion64\node_env-default\Scripts\prettier.cmd I'm not sure but there is some kind of a .CMD file command length limit.

It's easy to reproduce:

• Make simple file a.CMD with content: ECHO "WORKS"
• run python
• subprocess.Popen([a_file_abs_path] + ['x'] * 4000) It works (in single line it's ~8k chars)
• subprocess.Popen([a_file_abs_path] + ['x'] * 5000) It wasn't

pre-commit command executes a .CMD file with command which contains ~30k chars (of course it is greater than the limit).

[asottile]

hmmm so you're saying any .cmd script has an even shorter limit than the actual limit?

[apietrzak]

@asottile Yeah, from my tests it looks like that. I've tested it on two different machines with Win10, and i've got the same error when the command is larger than ~8k chars

[asottile]

hmmm ok, I've made #1686 to fix this, I've also figured out exactly the limit for cmd, it has to do with the full path to cmd.exe + /c

[apietrzak]

@asottile Thanks a lot, i'm waiting for a new version.

[asottile]

if you don't want to wait, you can pip install git+https://github.com/pre-commit/pre-commit