jestjs/jest · error · NotFoundPackageJsonError

Could not find a "package.json" file in ${rootDir}

Error message

Could not find a "package.json" file in ${rootDir}

What it means

create-jest (the engine behind `jest --init`) calls runCreate(rootDir), resolves projectPackageJsonPath, and checks fs.existsSync. If package.json is missing it throws NotFoundPackageJsonError. Jest's initializer assumes a Node project already exists because it wants to add a `test` script and optionally a `jest` property to package.json, so a missing manifest is a hard stop rather than a prompt.

Source

Thrown at packages/create-jest/src/runCreate.ts:56

    clearLine(process.stdout);
    if (error instanceof Error && Boolean(error?.stack)) {
      console.error(chalk.red(error.stack));
    } else {
      console.error(chalk.red(error));
    }

    exit(1);
    throw error;
  }
}

export async function runCreate(rootDir = process.cwd()): Promise<void> {
  rootDir = tryRealpath(rootDir);
  // prerequisite checks
  const projectPackageJsonPath = path.join(rootDir, PACKAGE_JSON);

  if (!fs.existsSync(projectPackageJsonPath)) {
    throw new NotFoundPackageJsonError(rootDir);
  }

  const questions = [...defaultQuestions];
  let hasJestProperty = false;
  let projectPackageJson: ProjectPackageJson;

  try {
    projectPackageJson = JSON.parse(
      fs.readFileSync(projectPackageJsonPath, 'utf8'),
    ) as ProjectPackageJson;
  } catch {
    throw new MalformedPackageJsonError(projectPackageJsonPath);
  }

  if (projectPackageJson.jest) {
    hasJestProperty = true;
  }

View on GitHub (pinned to f49721c78e)

Solutions

1. Run `npm init -y` (or `yarn init -y`) in the target directory first, then re-run create-jest.
2. Run create-jest from the directory that already contains package.json, or pass that directory as the rootDir argument.
3. If you intentionally have no package.json, create a minimal one with `{ "name": "..." }` before initializing.

Example fix

# before
mkdir myapp && cd myapp && npx create-jest   # fails: no package.json

# after
cd myapp && npm init -y && npx create-jest

const fs = require('node:fs');
const path = require('node:path');
const rootDir = process.argv[2] ?? process.cwd();
if (!fs.existsSync(path.join(rootDir, 'package.json'))) {
  console.error('No package.json in', rootDir, '- run `npm init -y` first.');
  process.exit(1);
}
// safe to call runCreate now

function hasPackageJson(rootDir: string): boolean {
  return fs.existsSync(path.join(rootDir, 'package.json'));
}

try {
  await runCreate(rootDir);
} catch (e) {
  if (e instanceof NotFoundPackageJsonError) {
    // create package.json then retry, or prompt the user
  }
  throw e;
}

When it happens

Trigger: Running `npx create-jest` or `jest --init` inside an empty/scratch directory, a directory above any package, or passing a rootDir argument that points somewhere without package.json (e.g. a subdir like ./src).

Common situations: Trying to bootstrap Jest in a fresh sandbox before `npm init`; running the initializer from the wrong cwd in a monorepo (root vs. package); CI containers that clone only a subfolder.

Related errors

• There is malformed json in ${packageJsonPath}
• babel-jest: Babel ignores ${slash(path.relative(cwd, filenam
• received value must be a mock or spy function
• received value must be a mock function
• Configuration in ${packageJson} is not valid. Jest expects t

AI-assisted analysis of jestjs/jest@f49721c78e (2026-08-03). Data as JSON: /data/errors/0a17f29a723b20f6.json. Report an issue: GitHub.