Property 'expand' does not exist on type 'MatcherUtils'.

[haldunanil]

🐛 Bug Report

When using TypeScript 3.1.1 with Jest 23.6.0, I get an error when trying to expand Jest's expect with a custom method.

To Reproduce

    if (pass) {
      ...
    } else {
      const diffString = diff(expected, received, {
        expand: this.expand
      });

      ...
    }

this.expand throws the TS2339 error mentioned in the title.

Expected behavior

this.expand should work as intended.

Link to repl or repo (highly encouraged)

N/A

Run npx envinfo --preset jest

Paste the results here:

  System:
    OS: macOS High Sierra 10.13.6
    CPU: x64 Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz
  Binaries:
    Node: 8.9.0 - ~/.nvm/versions/node/v8.9.0/bin/node
    Yarn: 1.9.4 - /usr/local/bin/yarn
    npm: 5.5.1 - ~/.nvm/versions/node/v8.9.0/bin/npm

[rickhanlonii]

Hey @haldunanil, thanks for using Jest!

If you're able to complete the issue template, I'm happy to re-open and take a look 👍

[haldunanil]

@rickhanlonii yeah my bad, trigger fingers, submitted too soon. Please have a look now :)

[rickhanlonii]

Thanks for the deets @haldunanil

Where did you see the usage of this.expand you expect? Is it possible to create a repro to repro?

[haldunanil]

this.expand is used here, the full code of the expansion that's throwing the error: https://github.com/haldunanil/jest-contain-object/blob/master/index.js

The this.expand part was inspired by the example in the Jest documentation here: https://jestjs.io/docs/en/expect#custom-matchers-api, the code block that begins with:

const diff = require('jest-diff');
expect.extend({
  toBe(received, expected) {
    const pass = Object.is(received, expected);
...

[SimenB]

Seems like an error in whatever TS typings you use - Jest doesn't ship with typings and this.expand is available (added here: https://github.com/facebook/jest/blob/ec382f527e75e0d6932e3e3954187d8a4d6c6240/packages/jest-jasmine2/src/jest_expect.js#L30). Happy to reopen if I'm mistaken!

[haldunanil]

@SimenB can you clarify how to use this?

[SimenB]

Clarify what? Your typing is wrong, it works. this.expand is a boolean inside of a matcher

[haldunanil]

I'm not clear on how what the correct typing should look like.

[SimenB]

It's a Boolean. Please open up an issue with whatever project you got typings from. Jest does not ship any typings at all, so this is not the correct place to raise an issue for it

[github-actions]

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