Jest: Running with coverage option throws "Cannot find module 'lcov'"

Created on 25 Mar 2020  ·  5Comments  ·  Source: facebook/jest

🐛 Bug Report

Running with jest --coverage throws the following error:

yarn run v1.19.1
$ jest --coverage
 PASS  src/index.test.js
  add
    ✓ should work (3ms)

----------|---------|----------|---------|---------|-------------------
File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
----------|---------|----------|---------|---------|-------------------
All files |     100 |      100 |     100 |     100 |
 index.js |     100 |      100 |     100 |     100 |
----------|---------|----------|---------|---------|-------------------

        Failed to write coverage reports:
        ERROR: Error: Cannot find module 'lcov'
Require stack:
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/istanbul-reports/index.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/reporters/build/coverage_reporter.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/reporters/build/index.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/core/build/TestScheduler.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/core/build/jest.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/jest-cli/build/cli/index.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/jest-cli/bin/jest.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/jest/bin/jest.js
        STACK: Error: Cannot find module 'lcov'
Require stack:
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/istanbul-reports/index.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/reporters/build/coverage_reporter.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/reporters/build/index.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/core/build/TestScheduler.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/core/build/jest.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/jest-cli/build/cli/index.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/jest-cli/bin/jest.js
- /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/jest/bin/jest.js
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:892:15)
    at Function.Module._load (internal/modules/cjs/loader.js:785:27)
    at Module.require (internal/modules/cjs/loader.js:956:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Object.create (/Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/istanbul-reports/index.js:19:20)
    at /Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/reporters/build/coverage_reporter.js:300:20
    at Array.forEach (<anonymous>)
    at CoverageReporter.onRunComplete (/Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/reporters/build/coverage_reporter.js:298:25)
    at ReporterDispatcher.onRunComplete (/Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/core/build/ReporterDispatcher.js:71:10)
    at TestScheduler.scheduleTests (/Users/shihsyuanyan/Desktop/test/jest-coverage-issue/node_modules/@jest/core/build/TestScheduler.js:280:5)

Test Suites: 1 passed, 1 total
Tests:       1 passed, 1 total
Snapshots:   0 total
Time:        0.48s, estimated 1s
Ran all test suites.

To Reproduce

  1. Create a new folder and initialize with yarn init
  2. yarn add --dev jest
  3. yarn run jest --init
  4. write some tests
  5. yarn run jest --coverage
  6. It throws errors

Expected behavior

I checked the coverageReports option in the documentation. It should generate lcov related reports without any error, I guess?

Link to repl or repo (highly encouraged)

jest-coverage-issue. Simply run yarn run test:cov to reproduce the error.

envinfo

  System:
    OS: macOS Mojave 10.14.1
    CPU: (8) x64 Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz
  Binaries:
    Node: 13.1.0 - ~/.nvm/versions/node/v13.1.0/bin/node
    Yarn: 1.19.1 - /usr/local/bin/yarn
    npm: 6.12.1 - ~/.nvm/versions/node/v13.1.0/bin/npm
  npmPackages:
    jest: ^25.1.0 => 25.1.0
Bug Report Needs Repro Needs Triage
Source
picture zushenyan
👍2

Most helpful comment

That's weird, some bug in node then? Closing, but can reopen if it's reproducible in current versions of node

picture SimenB on 25 Mar 2020
👍4

All 5 comments

I cannot reproduce this from your reproduction

image

SimenB picture SimenB on 25 Mar 2020

I'm able to reproduce.

System:
  Model Name:   MacBook Pro
  Model Identifier: MacBookPro12,1
  Processor Name:   Intel Core i5
  Processor Speed:  2.7 GHz
  OS: macOS Movaje 10.14.6
Binaries:
  Yarn: 1.3.2
  Node: 13.0.0
  npm: 6.14.3
Packages:
  Jest v25.1 .0

Stack trace:

Failed to write coverage reports:
        ERROR: Error: Cannot find module 'lcov'
Require stack:
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/istanbul-reports/index.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/reporters/build/coverage_reporter.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/reporters/build/index.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/core/build/TestScheduler.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/core/build/jest.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/jest-cli/build/cli/index.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/jest-cli/bin/jest.js
        STACK: Error: Cannot find module 'lcov'
Require stack:
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/istanbul-reports/index.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/reporters/build/coverage_reporter.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/reporters/build/index.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/core/build/TestScheduler.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/core/build/jest.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/jest-cli/build/cli/index.js
- /Users/famoraes/Documents/Projects/React/telescopio/node_modules/jest-cli/bin/jest.js
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:795:15)
    at Function.Module._load (internal/modules/cjs/loader.js:688:27)
    at Module.require (internal/modules/cjs/loader.js:850:19)
    at require (internal/modules/cjs/helpers.js:74:18)
    at Object.create (/Users/famoraes/Documents/Projects/React/telescopio/node_modules/istanbul-reports/index.js:19:20)
    at /Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/reporters/build/coverage_reporter.js:300:20
    at Array.forEach (<anonymous>)
    at CoverageReporter.onRunComplete (/Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/reporters/build/coverage_reporter.js:298:25)
    at processTicksAndRejections (internal/process/task_queues.js:93:5)
    at ReporterDispatcher.onRunComplete (/Users/famoraes/Documents/Projects/React/telescopio/node_modules/@jest/core/build/ReporterDispatcher.js:71:10)
famoraes picture famoraes on 25 Mar 2020

Solved upgrade node version to v13.11.0.

famoraes picture famoraes on 25 Mar 2020

That's weird, some bug in node then? Closing, but can reopen if it's reproducible in current versions of node

SimenB picture SimenB on 25 Mar 2020
👍4

I have the same problem. I tried to clone my project to another folder and it worked for the first time and never succeeded again.

dshung1997 picture dshung1997 on 11 Aug 2020
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