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Gathering detailed insights and metrics for esmock

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Gathering detailed insights and metrics for esmock

esmock - 2.7.1 | npmpackage.info

esmock

ESM import and globals mocking for unit tests

2.7.1

206

ISC

JavaScript

25.62 kB

3.9

Installations

npm install esmock

Developer Guide

BETA

Typescript

Yes

Module System

ESM

Min. Node Version

>=14.16.0

Node Version

22.16.0

NPM Version

11.3.0 Pull Requests

Open

1

Total

232

Closed

8

Merged

223

Issues

Open

5

Total

92

Closed

87

Releases

add node v24 to test matrix

v2.7.1

Updated on Jul 01, 2025

resolve openai mocking

v2.7.0

Updated on Jan 24, 2025

support node v23

v2.6.9

Updated on Oct 18, 2024

add pnpm test

v2.6.8

Updated on Oct 18, 2024

add swc tests

v2.6.7

Updated on Jul 16, 2024

migrate eslint 9 add tsx tests

v2.6.6

Updated on Jun 15, 2024

View All 97 releases

Languages

JavaScript

TypeScript

JavaScript (92.6%)

TypeScript (7.4%)

Developer

iambumblehead

Download Statistics

Total Downloads

Last Day

Last Week

Last Month

Last Year

GitHub Statistics

ISC License

206 Stars

1,124 Commits

20 Forks

4 Watchers

2 Branches

14 Contributors

Updated on Jul 01, 2025

Maintainers

View All 14 Contributors

Package Meta Information

Latest Version

2.7.1

Package Id

esmock@2.7.1

Unpacked Size

25.62 kB

Size

9.85 kB

File Count

NPM Version

11.3.0

Node Version

22.16.0

Published on

Jul 01, 2025

Total Downloads

Cumulative downloads

Total Downloads

NaN

Last Day

NaN

Compared to previous day

Last Week

NaN

Compared to previous week

Last Month

NaN

Compared to previous month

Last Year

NaN

Compared to previous year

Weekly Downloads

Monthly Downloads

Yearly Downloads

No dependencies detected.

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esmock provides native ESM import and globals mocking for unit tests. Use examples below as a quick-start guide, see the descriptive and friendly esmock guide here, or browse esmock's test runner examples.

Note: For versions of node prior to v20.6.0, "--loader" command line arguments must be used with esmock as demonstrated in the wiki. Current versions of node do not require "--loader".

Note: due to --loader issues, support for ava and jest are dropped.

esmock has the below signature

1await esmock(
2  './to/module.js', // path to target module being tested
3  { ...childmocks }, // mock definitions imported by target module
4  { ...globalmocks }) // mock definitions imported everywhere

esmock examples

1import test from 'node:test'
2import assert from 'node:assert'
3import esmock from 'esmock'
4
5test('package, alias and local file mocks', async () => {
6  const cookup = await esmock('../src/cookup.js', {
7    addpkg: (a, b) => a + b,
8    '#icon': { coffee: '☕', bacon: '🥓' },
9    '../src/breakfast.js': {
10      default: () => ['coffee', 'bacon'],
11      addSalt: meal => meal + '🧂'
12    }
13  })
14
15  assert.equal(cookup('breakfast'), '☕🥓🧂')
16})
17
18test('full import tree mocks —third param', async () => {
19  const { getFile } = await esmock('../src/main.js', {}, {
20    // mocks *every* fs.readFileSync inside the import tree
21    fs: { readFileSync: () => 'returned to 🌲 every caller in the tree' }
22  })
23
24  assert.equal(getFile(), 'returned to 🌲 every caller in the tree')
25})
26
27test('mock fetch, Date, setTimeout and any globals', async () => {
28  // https://github.com/iambumblehead/esmock/wiki#call-esmock-globals
29  const { userCount } = await esmock('../Users.js', {
30    '../req.js': await esmock('../req.js', {
31      import: { // define globals like 'fetch' on the import namespace
32        fetch: async () => ({
33          status: 200,
34          json: async () => [['jim','😄'],['jen','😊']]
35        })
36      }
37    })
38  })
39
40  assert.equal(await userCount(), 2)
41})
42
43test('mocks "await import()" using esmock.p', async () => {
44  // using esmock.p, mock definitions are kept in cache
45  const doAwaitImport = await esmock.p('../awaitImportLint.js', {
46    eslint: { ESLint: cfg => cfg }
47  })
48
49  // mock definition is returned from cache, when import is called
50  assert.equal(await doAwaitImport('cfg🛠️'), 'cfg🛠️')
51  // a bit more info are found in the wiki guide
52})
53
54test('esmock.strict mocks', async () => {
55  // replace original module definitions and do not merge them
56  const pathWrapper = await esmock.strict('../src/pathWrapper.js', {
57    path: { dirname: () => '/path/to/file' }
58  })
59
60  // error, because "path" mock above does not define path.basename
61  assert.rejects(() => pathWrapper.basename('/dog.🐶.png'), {
62    name: 'TypeError',
63    message: 'path.basename is not a function'
64  })
65})

No vulnerabilities found.

10

Dangerous-Workflow

Determines if the project's GitHub Action workflows avoid dangerous patterns.

10

Binary-Artifacts

Determines if the project has generated executable (binary) artifacts in the source repository.

10

License

Determines if the project has defined a license.

10

Vulnerabilities

Determines if the project has open, known unfixed vulnerabilities.

1

Maintained

Determines if the project is "actively maintained".

0

Code-Review

Determines if the project requires human code review before pull requests (aka merge requests) are merged.

0

CII-Best-Practices

Determines if the project has an OpenSSF (formerly CII) Best Practices Badge.

0

Pinned-Dependencies

Determines if the project has declared and pinned the dependencies of its build process.

Reason

dependency not pinned by hash detected -- score normalized to 0

Details

Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/coverage.yml:14: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/coverage.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/coverage.yml:15: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/coverage.yml/main?enable=pin
Warn: third-party GitHubAction not pinned by hash: .github/workflows/coverage.yml:37: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/coverage.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/lint.yml:13: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/lint.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/publish.yml:11: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/publish.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/publish.yml:20: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/publish.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/publish.yml:21: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/publish.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/test-pnpm.yml:19: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/test-pnpm.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/test-pnpm.yml:20: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/test-pnpm.yml/main?enable=pin
Warn: third-party GitHubAction not pinned by hash: .github/workflows/test-pnpm.yml:23: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/test-pnpm.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/test.yml:19: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/test.yml/main?enable=pin
Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/test.yml:20: update your workflow using https://app.stepsecurity.io/secureworkflow/iambumblehead/esmock/test.yml/main?enable=pin
Warn: npmCommand not pinned by hash: .github/workflows/coverage.yml:19
Warn: npmCommand not pinned by hash: .github/workflows/lint.yml:17
Warn: npmCommand not pinned by hash: .github/workflows/publish.yml:13
Warn: npmCommand not pinned by hash: .github/workflows/publish.yml:39
Warn: npmCommand not pinned by hash: .github/workflows/test-pnpm.yml:27
Warn: npmCommand not pinned by hash: .github/workflows/test.yml:24
Info: 0 out of 10 GitHub-owned GitHubAction dependencies pinned
Info: 0 out of 2 third-party GitHubAction dependencies pinned
Info: 0 out of 6 npmCommand dependencies pinned

0

Token-Permissions

Determines if the project's workflows follow the principle of least privilege.

0

Security-Policy

Determines if the project has published a security policy.

0

Fuzzing

Determines if the project uses fuzzing.

0

SAST

Determines if the project uses static code analysis.

Score

3.9

/10

Last Scanned on 2025-07-07

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