Before: Save g:ale_biome_options Save g:ale_biome_lsp_project_root let g:ale_biome_options = '' let g:ale_biome_lsp_project_root = '' 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(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' Execute(Should find project root containing biome.json): call ale#test#SetFilename('../test-files/biome/json/src/test.ts') AssertLSPProject ale#path#Simplify(g:dir . '/../test-files/biome/json') Execute(Should find project root containing biome.jsonc): call ale#test#SetFilename('../test-files/biome/jsonc/src/test.ts') AssertLSPProject ale#path#Simplify(g:dir . '/../test-files/biome/jsonc') Execute(Should use user-specified project root): let g:ale_biome_lsp_project_root = '/' call ale#test#SetFilename('../test-files/biome/jsonc/src/test.ts') AssertLSPProject '/'