Before: Save g:ale_biome_options let g:ale_biome_options = '' call ale#assert#SetUpLinterTest('typescript', 'biome') call ale#test#SetFilename('test.ts') After: call ale#assert#TearDownLinterTest() Execute(The default biome command should be correct): AssertLinter 'biome', ale#Escape('biome') . ' lsp-proxy' Execute(The biome command should accept options): let g:ale_biome_options = '--foobar' AssertLinter 'biome', ale#Escape('biome') . ' lsp-proxy --foobar' Execute(Uses the filetype as the language): call ale#test#SetFilename('test.ts') set filetype=typescript AssertLSPLanguage 'typescript' call ale#test#SetFilename('test.tsx') set filetype=typescriptreact AssertLSPLanguage 'typescriptreact' call ale#test#SetFilename('test.js') set filetype=javascript AssertLSPLanguage 'javascript' call ale#test#SetFilename('test.jsx') set filetype=javascriptreact AssertLSPLanguage 'javascriptreact'