Single test file causing "heap out of memory"

🐛 Bug Report

Jest is crashing when running a single test file. Example failing CI log can be found here.

Issue seems to be related to the following function being called many times:

const waitForAsync = (delay = 20) => new Promise(resolve => setTimeout(resolve, delay));

To Reproduce

1. Checkout the branch

git clone https://github.com/andyrichardson/tipple.git
cd tipple
git checkout 03819cf06bd9a750d7958c5d0332607d6d3860ce

1. Run tests

npm run test -- --watch useFetch

Expected behavior

Tests run and at the very worst, fail.

Actual behaviour

Tests crash and don’t terminate until a heap error.

Link to repl or repo (highly encouraged)

See above

Additional info

• Commenting out the await waitForAsync(); calls on lines 234/237 causes the test to complete

• Running any tests in isolation causes tests to complete

• Calling global.gc() after each test does not resolve the issue.

Run npx envinfo --preset jest

Note: this is failing on macOS and Linux

Paste the results here:

  System:
    OS: macOS 10.14.5
    CPU: (12) x64 Intel(R) Core(TM) i7-8850H CPU @ 2.60GHz
  Binaries:
    Node: 8.12.0 - ~/.nvm/versions/node/v8.12.0/bin/node
    Yarn: 1.12.3 - ~/.nvm/versions/node/v8.12.0/bin/yarn
    npm: 6.9.0 - ~/.nvm/versions/node/v8.12.0/bin/npm
  npmPackages:
    jest: 24.8.0 => 24.8.0

[andyrichardson]

Wanted to follow up on this - I’ve seen problem on many different projects since reporting this (my own and other people’s).

Pretty sure it’s a memory leak - #7874

[github-actions[bot]]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs. Please note this issue tracker is not a help forum. We recommend using StackOverflow or our discord channel for questions.