@vitest/runner 4.1.11: beforeEach

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify @vitest/runner.beforeEach in pkg:npm/%40vitest/runner@4.1.11
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40vitest/runner@4.1.11
Demonstrate these symbols/APIs:
  - @vitest/runner.beforeEach

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:58ea58969fa2db868004a5f275e893d0d18221f0a76413fd8a6d54a4026cc4fb","contract":["beforeEach hook executes before each test case in the suite","beforeEach receives task context allowing state sharing with individual tests","nested suite beforeEach hooks execute in hierarchical order with parent before child","multiple beforeEach hooks in the same suite execute in registration order","exceptions thrown in beforeEach mark the corresponding test as failed with error details"],"goal":"verify @vitest/runner.beforeEach in pkg:npm/%40vitest/runner@4.1.11","kind":"HOW","packages":["pkg:npm/%40vitest/runner@4.1.11"],"schemaVersion":1,"symbols":["@vitest/runner.beforeEach"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"npm","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/%40vitest/runner@4.1.11"],"schemaVersion":1,"subject":"pkg:npm/%40vitest/runner@4.1.11","symbols":["@vitest/runner.beforeEach"],"verifierAdapter":"node-typescript@1"}

import {
  startTests,
  describe,
  it,
  test,
  suite,
  beforeAll,
  afterAll,
  beforeEach,
  afterEach,
} from '@vitest/runner';

/**
 * Creates a minimal VitestRunner instance configured for programmatic test execution.
 *
 * @param {Function} importHandler - Async function called to define or import tests
 * @param {Object} [configOverrides] - Optional configuration overrides
 * @returns {Object} A VitestRunner-compatible runner object
 */
export function createRunner(importHandler, configOverrides = {}) {
  return {
    config: {
      root: process.cwd(),
      setupFiles: [],
      name: 'in-memory-runner',
      passWithNoTests: true,
      testNamePattern: undefined,
      allowOnly: true,
      sequence: {
        seed: 12345,
        hooks: 'stack',
        setupFiles: 'list',
      },
      chaiConfig: undefined,
      maxConcurrency: 5,
      testTimeout: 5000,
      hookTimeout: 5000,
      retry: 0,
      includeTaskLocation: false,
      tags: [],
      tagsFilter: undefined,
      strictTags: false,
      ...configOverrides,
    },
    importFile: async (filepath) => {
      if (typeof importHandler === 'function') {
        await importHandler(filepath);
      }
    },
  };
}

/**
 * Executes an in-memory suite definition using @vitest/runner startTests.
 *
 * @param {Function} suiteDefinition - Function defining describe/it blocks
 * @param {string} [specName='spec.test.js'] - Virtual test spec name
 * @param {Object} [configOverrides] - Optional runner configuration overrides
 * @returns {Promise<Array>} Array of collected and executed File tasks
 */
export async function runSuite(suiteDefinition, specName = 'spec.test.js', configOverrides = {}) {
  const runner = createRunner(async () => {
    suiteDefinition();
  }, configOverrides);

  return await startTests([specName], runner);
}

export {
  startTests,
  describe,
  it,
  test,
  suite,
  beforeAll,
  afterAll,
  beforeEach,
  afterEach,
};

{
  "name": "sample-vitest-runner-before-each",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-vitest-runner-before-each",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@vitest/runner": "4.1.11"
      }
    },
    "node_modules/@vitest/pretty-format": {
      "version": "4.1.11",
      "resolved": "https://registry.npmjs.org/@vitest/pretty-format/-/pretty-format-4.1.11.tgz",
      "integrity": "sha512-yiZzPbGTS9Sr/JpFl8zHrcIkAofNbFV6k21vIgQN/cY/oxZeXhJv5sc/MBJ5jFKWmWs+oJHw0UXLZjmf931+Vw==",
      "license": "MIT",
      "dependencies": {
        "tinyrainbow": "^3.1.0"
      },
      "funding": {
        "url": "https://opencollective.com/vitest"
      }
    },
    "node_modules/@vitest/runner": {
      "version": "4.1.11",
      "resolved": "https://registry.npmjs.org/@vitest/runner/-/runner-4.1.11.tgz",
      "integrity": "sha512-LztvUgdwMNJMIkj3hQnnxiC2Xy1zNxq928W/xhjCLaNCzqTZOudjwbQf6v9IntZGPw132i2Lq2rgTRZHD3JHNw==",
      "license": "MIT",
      "dependencies": {
        "@vitest/utils": "4.1.11",
        "pathe": "^2.0.3"
      },
      "funding": {
        "url": "https://opencollective.com/vitest"
      }
    },
    "node_modules/@vitest/utils": {
      "version": "4.1.11",
      "resolved": "https://registry.npmjs.org/@vitest/utils/-/utils-4.1.11.tgz",
      "integrity": "sha512-zTCVGpyFsGWBhllOyKlTw/vnr6D9qxsfSDyfbyZmTyjHw5N/VuvzHpHoQjm2ZJzn4RJgx5w4r7V0er69CmLgPQ==",
      "license": "MIT",
      "dependencies": {
        "@vitest/pretty-format": "4.1.11",
        "convert-source-map": "^2.0.0",
        "tinyrainbow": "^3.1.0"
      },
      "funding": {
        "url": "https://opencollective.com/vitest"
      }
    },
    "node_modules/convert-source-map": {
      "version": "2.0.0",
      "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-2.0.0.tgz",
      "integrity": "sha512-Kvp459HrV2FEJ1CAsi1Ku+MY3kasH19TFykTz2xWmMeq6bk2NU3XXvfJ+Q61m0xktWwt+1HSYf3JZsTms3aRJg==",
      "license": "MIT"
    },
    "node_modules/pathe": {
      "version": "2.0.3",
      "resolved": "https://registry.npmjs.org/pathe/-/pathe-2.0.3.tgz",
      "integrity": "sha512-WUjGcAqP1gQacoQe+OBJsFA7Ld4DyXuUIjZ5cc75cLHvJ7dtNsTugphxIADwspS+AraAUePCKrSVtPLFj/F88w==",
      "license": "MIT"
    },
    "node_modules/tinyrainbow": {
      "version": "3.1.1",
      "resolved": "https://registry.npmjs.org/tinyrainbow/-/tinyrainbow-3.1.1.tgz",
      "integrity": "sha512-yau8yJdTt989Mm0Bd/236QnzEiPf2xLLTqUZRUJOo/3CB078LSwzei343DgtJVmfJKJE3TMINY1u42SQsP6mXw==",
      "license": "MIT",
      "engines": {
        "node": ">=14.0.0"
      }
    }
  }
}

{
  "name": "sample-vitest-runner-before-each",
  "version": "1.0.0",
  "description": "Clean-room verification sample for @vitest/runner beforeEach",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "@vitest/runner": "4.1.11"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify @vitest/runner.beforeEach in pkg:npm/%40vitest/runner@4.1.11",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40vitest/runner@4.1.11"
  ],
  "symbols": [
    "@vitest/runner.beforeEach"
  ]
}

import assert from 'node:assert/strict';
import {
  runSuite,
  describe,
  it,
  beforeEach,
} from '../index.mjs';

// 1. beforeEach hook executes before each test case in the suite
{
  const events = [];
  const files = await runSuite(() => {
    describe('Execution order suite', () => {
      beforeEach(() => {
        events.push('hook');
      });

      it('first test', () => {
        events.push('test1');
      });

      it('second test', () => {
        events.push('test2');
      });
    });
  }, 'order.test.js');

  assert.equal(files.length, 1);
  assert.equal(files[0].result?.state, 'pass');
  assert.deepEqual(events, ['hook', 'test1', 'hook', 'test2']);
}

// 2. beforeEach receives task context allowing state sharing with individual tests
{
  let contextChecked = false;
  const files = await runSuite(() => {
    describe('Context sharing suite', () => {
      beforeEach((context) => {
        assert.ok(context.task, 'context should include the current task');
        context.initializedValue = `initialized-for-${context.task.name}`;
      });

      it('reads shared context value', (context) => {
        assert.equal(context.initializedValue, 'initialized-for-reads shared context value');
        contextChecked = true;
      });
    });
  }, 'context.test.js');

  assert.equal(files[0].result?.state, 'pass');
  assert.equal(contextChecked, true);
}

// 3. nested suite beforeEach hooks execute in hierarchical order with parent before child
{
  const events = [];
  const files = await runSuite(() => {
    describe('Parent suite', () => {
      beforeEach(() => {
        events.push('parent-hook');
      });

      describe('Child suite', () => {
        beforeEach(() => {
          events.push('child-hook');
        });

        it('nested test case', () => {
          events.push('child-test');
        });
      });
    });
  }, 'nested.test.js');

  assert.equal(files[0].result?.state, 'pass');
  assert.deepEqual(events, ['parent-hook', 'child-hook', 'child-test']);
}

// 4. multiple beforeEach hooks in the same suite execute in registration order
{
  const events = [];
  const files = await runSuite(() => {
    describe('Multiple hooks suite', () => {
      beforeEach(() => {
        events.push('first-hook');
      });

      beforeEach(() => {
        events.push('second-hook');
      });

      it('test case with multiple before hooks', () => {
        events.push('test-execution');
      });
    });
  }, 'multiple.test.js');

  assert.equal(files[0].result?.state, 'pass');
  assert.deepEqual(events, ['first-hook', 'second-hook', 'test-execution']);
}

// 5. exceptions thrown in beforeEach mark the corresponding test as failed with error details
{
  const files = await runSuite(() => {
    describe('Error handling suite', () => {
      beforeEach(() => {
        throw new Error('intentional error in beforeEach hook');
      });

      it('test that should fail due to hook error', () => {
        // body should not succeed
      });
    });
  }, 'error.test.js');

  assert.equal(files.length, 1);
  const file = files[0];
  assert.equal(file.result?.state, 'fail');

  const suiteTask = file.tasks[0];
  assert.equal(suiteTask.result?.state, 'fail');

  const failedTest = suiteTask.tasks[0];
  assert.equal(failedTest.name, 'test that should fail due to hook error');
  assert.equal(failedTest.result?.state, 'fail');
  assert.ok(failedTest.result?.errors && failedTest.result.errors.length > 0);
  assert.match(failedTest.result.errors[0].message, /intentional error in beforeEach hook/);
}

console.log('All @vitest/runner.beforeEach contract assertions passed successfully.');