[SvelteKit + TS] SyntaxError: Unexpected identifier 'Promise'

[vojtechsimetka]

Knip@3 does not work with SvelteKit@2 with Typescript enabled. It works just with with JS only or in SvelteKit@1 and svelte@3.

Error output

Analyzing workspace ....
The CJS build of Vite's Node API is deprecated. See https://vitejs.dev/guide/troubleshooting.html#vite-cjs-node-api-deprecated for more details.
Error loading /Users/vojtechsimetka/Repos/testdemo/test/vite.config.ts
Reason: Unexpected identifier 'Promise'

How to reproduce

1. Create new SvelteKit project and enable Typescript. You also need to build the project because .svelte-kit/tsconfig.json does not exist at this point.

pnpm create svelte@latest test && \
cd test && \
pnpm i && \
pnpm build

2. Run knip

pnpx knip

Debug output

Click to expand

[*] Unresolved configuration (from CLI arguments)
{
  cwd: '/Users/testuser/test',
  tsConfigFile: undefined,
  gitignore: true,
  isProduction: false,
  isStrict: false,
  isShowProgress: false,
  isIncludeEntryExports: false,
  isIsolateWorkspaces: false,
  isFix: false,
  fixTypes: []
}
[*] Included workspaces
[ 'test' ]
[*] Included workspace configs
[
  {
    pkgName: 'test',
    name: '.',
    config: {
      entry: [
        '{index,cli,main}.{js,mjs,cjs,jsx,ts,tsx,mts,cts}!',
        'src/{index,cli,main}.{js,mjs,cjs,jsx,ts,tsx,mts,cts}!'
      ],
      project: [ '**/*.{js,mjs,cjs,jsx,ts,tsx,mts,cts}!' ],
      paths: {},
      ignore: [],
      ignoreBinaries: [],
      ignoreDependencies: [],
      isIncludeEntryExports: false
    },
    ancestors: []
  }
]
[.] Enabled plugins (.)
[ 'Svelte', 'TypeScript', 'Vite' ]
[.] Definition paths (7)
[
  '/Users/testuser/test/.svelte-kit/ambient.d.ts',
  '/Users/testuser/test/.svelte-kit/non-ambient.d.ts',
  '/Users/testuser/test/.svelte-kit/types/src/routes/$types.d.ts',
  '/Users/testuser/test/.svelte-kit/types/src/routes/about/$types.d.ts',
  '/Users/testuser/test/.svelte-kit/types/src/routes/sverdle/$types.d.ts',
  '/Users/testuser/test/.svelte-kit/types/src/routes/sverdle/how-to-play/$types.d.ts',
  '/Users/testuser/test/src/app.d.ts'
]
[.] Entry paths in package.json (0)
[]
[.] Svelte config file paths (0)
[]
[.] Svelte dependencies (5)
[
  'entry:svelte.config.js',
  'entry:vite*.config.{js,mjs,ts,cjs,mts,cts}',
  'production:src/hooks.{server,client}.{js,ts}',
  'production:src/params/*{js,ts}',
  'production:src/routes/**/+{page,server,page.server,error,layout,layout.server}{,@*}.{js,ts,svelte}'
]
[.] TypeScript config file paths (1)
[ '/Users/testuser/test/tsconfig.json' ]
[.] TypeScript dependencies (0)
[]
[.] Vite config file paths (1)
[ '/Users/testuser/test/vite.config.ts' ]
The CJS build of Vite's Node API is deprecated. See https://vitejs.dev/guide/troubleshooting.html#vite-cjs-node-api-deprecated for more details.
file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/util/loader.js:37
        throw new LoaderError(`Error loading ${filePath}`, { cause: error });
              ^

LoaderError: Error loading /Users/testuser/test/vite.config.ts
    at load (file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/util/loader.js:37:15)
    at Module.findViteDependencies (file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/plugins/vite/index.js:9:31)
    at WorkspaceWorker.findDependenciesByPlugins (file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/WorkspaceWorker.js:193:59)
    at async WorkspaceWorker.findAllDependencies (file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/WorkspaceWorker.js:219:9)
    at async main (file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/index.js:120:30)
    at async run (file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/cli.js:23:73)
    at async file:///Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/knip@3.9.0_@types+node@20.10.5_typescript@5.3.3/node_modules/knip/dist/cli.js:77:1 {
  [cause]: /Users/testuser/test/node_modules/.pnpm/@sveltejs+kit@2.0.6_@sveltejs+vite-plugin-svelte@3.0.1_svelte@4.2.8_vite@5.0.10/node_modules/@sveltejs/kit/src/core/sync/ts.js:5
    exports.ts = ts = (await Promise.resolve().then(() => require('typescript'))).default;
                             ^^^^^^^
  
  SyntaxError: Unexpected identifier 'Promise'
      at new Script (node:vm:99:7)
      at createScript (node:vm:247:10)
      at Object.runInThisContext (node:vm:295:10)
      at evalModule (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:256254)
      at jiti (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:254371)
      at /Users/testuser/test/node_modules/.pnpm/@sveltejs+kit@2.0.6_@sveltejs+vite-plugin-svelte@3.0.1_svelte@4.2.8_vite@5.0.10/node_modules/@sveltejs/kit/src/core/sync/write_types/index.js:6:11
      at evalModule (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:256443)
      at jiti (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:254371)
      at /Users/testuser/test/node_modules/.pnpm/@sveltejs+kit@2.0.6_@sveltejs+vite-plugin-svelte@3.0.1_svelte@4.2.8_vite@5.0.10/node_modules/@sveltejs/kit/src/core/sync/sync.js:6:15
      at evalModule (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:256443)
      at jiti (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:254371)
      at /Users/testuser/test/node_modules/.pnpm/@sveltejs+kit@2.0.6_@sveltejs+vite-plugin-svelte@3.0.1_svelte@4.2.8_vite@5.0.10/node_modules/@sveltejs/kit/src/exports/vite/index.js:10:36
      at evalModule (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:256443)
      at jiti (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:254371)
      at /Users/testuser/test/vite.config.ts:1:175
      at evalModule (/Users/testuser/Library/pnpm/store/v3/tmp/dlx-69205/node_modules/.pnpm/jiti@1.21.0/node_modules/jiti/dist/jiti.js:1:256443)
}

Node.js v20.10.0

[vojtechsimetka]

Closing as a duplicate of #346

[webpro]

Fwiw, I've added the error message to https://knip.dev/reference/known-issues

[webpro]

Knip v5.1 introduce a new workaround: bunx --bun knip