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toBeInstanceOf( Function ) not working as expected.

See original GitHub issue

Jest 22.4.3

I’ve got this test, that works:

    expect( typeof bar.method ).toBe( 'function' ) // it works

but then this fails:

    expect( bar.method ).toBeInstanceOf( Function )

with output:

    expect(value).toBeInstanceOf(constructor)

    Expected value to be an instance of:
      "Function"
    Received:
      [Function method]
    Constructor:
      "Function"

      270 |     console.log('1')
      271 |     expect( typeof bar.method ).toBe( 'function' )
    > 272 |     expect( bar.method ).toBeInstanceOf( Function )
      273 |
      274 |     Bar = Class({
      275 |         method() {}

Seems like it should not fail.

Issue Analytics

State:
Created 5 years ago
Comments:9

Top GitHub Comments

1reaction

SimenBcommented, Apr 11, 2018

Closing as dupe, then. Follow that for updates (hope to have it solved for jest 23)

0reactions

github-actions[bot]commented, May 12, 2021

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.

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