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Naming the beforeEach function produces imprecise error: fn.call is not a function

See original GitHub issue

🐛 Bug Report

After migrating from mocha to jest. I got the following error for naming the beforeEach function:

TypeError: fn.call is not a function
at resolve (node_modules/jest-jasmine2/build/queue_runner.js:56:12)

To Reproduce

beforeEach('setup delegate.js', () => {
});

Expected behavior

A better error message, that points to the problem:

Link to repl

Link to reproduction.

Result:

Jest v22.1.2 node v7.4.0 linux/amd64
   
 FAIL  ./add-test.js
  add
    ✕ should add two numbers (7ms)

  ● add › should add two numbers

    TypeError: fn.call is not a function
      
      at resolve (../../usr/local/share/.config/yarn/global/node_modules/jest-jasmine2/build/queue_runner.js:52:12)

Test Suites: 1 failed, 1 total
Tests:       1 failed, 1 total
Snapshots:   0 total
Time:        0.981s
Ran all test suites.
exit status 1

Issue Analytics

State:
Created 5 years ago
Comments:5 (1 by maintainers)

Top GitHub Comments

2reactions

SimenBcommented, Aug 29, 2018

I’ll copy parts of my comment from #4613 for others to more easily contribute.

Wanna send a PR giving a better error?

For Jest Circus the code is here: https://github.com/facebook/jest/blob/c93e02718480b9f25b0d28f33456ed159bd11b69/packages/jest-circus/src/index.js#L42-L48 For Jest Jasmine it’s here: https://github.com/facebook/jest/blob/c93e02718480b9f25b0d28f33456ed159bd11b69/packages/jest-jasmine2/src/jasmine/Env.js#L505-L539

It’s a matter of type-checking that the first argument is indeed a function

1reaction

ranyitzcommented, Aug 29, 2018

Thanks @a1300 for reporting the issue and @SimenB for guidance.

I’ve created a PR with a fix - #6917

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