jestjs/jest · error · Error

Package '${pkg.name}' declares '@jest/test-utils' as dev dep

Error message

Package '${pkg.name}' declares '@jest/test-utils' as dev dependency, but it is not referenced in:

${tsConfigPaths.join('\n')}

What it means

After confirming @jest/test-utils is correctly in devDependencies, buildTs.mjs:115-140 globs each package's __tests__/tsconfig.json files and checks whether any references a path ending in 'test-utils'. If the package declares the devDependency but NO test tsconfig references it, the declaration is dead weight and the script throws. It enforces that a declared test-utils devDep is actually wired into the TS project references.

Source

Thrown at scripts/buildTs.mjs:131

  );

  const tsConfigPaths = glob.sync('**/__tests__/tsconfig.json', {
    absolute: true,
    cwd: packageDir,
  });

  const testUtilsReferences = tsConfigPaths.filter(tsConfigPath => {
    const tsConfig = JSON.parse(
      stripJsonComments(fs.readFileSync(tsConfigPath, 'utf8')),
    );

    return tsConfig.references.some(
      ({path}) => path && path.endsWith('test-utils'),
    );
  });

  if (hasJestTestUtils && testUtilsReferences.length === 0) {
    throw new Error(
      chalk.red(
        `Package '${
          pkg.name
        }' declares '@jest/test-utils' as dev dependency, but it is not referenced in:\n\n${tsConfigPaths.join(
          '\n',
        )}`,
      ),
    );
  }

  if (!hasJestTestUtils && testUtilsReferences.length > 0) {
    throw new Error(
      chalk.red(
        `Package '${
          pkg.name
        }' does not declare '@jest/test-utils' as dev dependency, but it is referenced in:\n\n${testUtilsReferences.join(
          '\n',
        )}`,

View on GitHub (pinned to f49721c78e)

Solutions

1. Add a project reference to test-utils in the relevant __tests__/tsconfig.json, e.g. { "references": [{ "path": "../../test-utils" }] }.
2. If the package no longer uses @jest/test-utils, remove it from devDependencies instead (note error 246 enforces the inverse).
3. Ensure the reference path string ends with 'test-utils' so the matcher at buildTs.mjs:126 fires.

Example fix

// before (packages/foo/__tests__/tsconfig.json)
{ "references": [] }
// after
{ "references": [{ "path": "../../test-utils" }] }

function assertTestUtilsReferenceExists(pkg, packageDir, glob, fs, stripJsonComments) {
  const isDevDep = Object.keys(pkg.devDependencies || {}).includes('@jest/test-utils');
  const tsConfigs = glob.sync('**/__tests__/tsconfig.json', { absolute: true, cwd: packageDir });
  const refs = tsConfigs.filter(p => {
    const cfg = JSON.parse(stripJsonComments(fs.readFileSync(p, 'utf8')));
    return (cfg.references || []).some(r => r.path && r.path.endsWith('test-utils'));
  });
  if (isDevDep && refs.length === 0) {
    throw new Error(`${pkg.name}: @jest/test-utils declared but not referenced in any __tests__/tsconfig.json`);
  }
}

When it happens

Trigger: Running scripts/buildTs.mjs when a package lists @jest/test-utils in devDependencies but none of its __tests__/tsconfig.json files contain a `references` entry pointing to the test-utils path.

Common situations: Adding @jest/test-utils to devDependencies preemptively before writing tests that use it; renaming/moving the test-utils reference so the `endsWith('test-utils')` check no longer matches; removing the tests but leaving the devDep.

Related errors

• Package '${pkg.name}' does not declare '@jest/test-utils' as
• Package '${pkg.name}' declares '@jest/test-utils' as depende
• ${file} has the following non-node type references: ${refer
• API Extractor completed with ${extractorResult.errorCount} e
• No exports found in package ${pkg.name}

AI-assisted analysis of jestjs/jest@f49721c78e (2026-08-03). Data as JSON: /data/errors/c3c5d4c5f3682349.json. Report an issue: GitHub.