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⏯ Playground Link

not applicable

💻 Code

I am on Windows trying to register the custom dart language from https://www.npmjs.com/package/@ast-grep/lang-dart and use it with the cli tool.

> md D:\ast-grep
> cd D:\ast-grep
> npm install --silent @ast-grep/lang-dart
> dir "node_modules\@ast-grep\lang-dart\prebuilds\prebuild-Windows-X64\
 Volume in drive D is Windows
 Volume Serial Number is 0DC3-13DD

 Directory of D:\ast-grep\node_modules\@ast-grep\lang-dart\prebuilds\prebuild-Windows-X64\parser.so

07.08.2025  16:17           766.976 parser.so
               1 File(s)        766.976 bytes
               0 Dir(s)  183.259.955.200 bytes free

D:\ast-grep\sgconfig.yaml:

ruleDirs: []
customLanguages:
  dart:
    libraryPath: "D:\\ast-grep\\node_modules\\@ast-grep\\lang-dart\\prebuilds\\prebuild-Windows-X64\\parser.so"
    extensions: [dart]

> set AST_GREP_CONFIG=D:\ast-grep-dart\sgconfig.yml
> echo class Foo { } | sg.exe run -l dart -p "class $NAME { }" -
error: invalid value 'dart' for '--lang <LANG>': dart is not supported!

For more information, try '--help'.

🙁 Actual behavior

sg.exe ignores the registered custom dart language and fails with error: invalid value 'dart' for '--lang <LANG>': dart is not supported!

🙂 Expected behavior

sg.exe picks up the config from sgconfig.yml and registers the configured dart customLanguage and allows me to use it.

Additional information about the issue

It would be extremely helpful if sg had a command display it's effective config or a verbose mode where one can see if any config files are loaded and applied.