Add fakeTimersLolex to implement JestEnvironment interface

[douglascayers]

Opening pull request per this conversation.

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• Use a meaningful title for the pull request. Include the name of the package modified.
• Test the change in your own code. (Compile and run.)
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• Provide a URL to documentation or source code which provides context for the suggested changes:
  • https://github.com/facebook/jest/releases/tag/v25.1.0
  • feat: add fakeTimersLolex to the test environments jestjs/jest#8925
  • jestjs/jest@0935f7c#diff-e8e69a5b9fa4b43b2e24abe1933d2855R44
• If this PR brings the type definitions up to date with a new version of the JS library, update the version number in the header.
• Include tests for your changes

[douglascayers]

@typescript-bot I've reviewed the build errors, but I don't know how to resolve them.

Azure Pipelines build result:

types/jest/index.d.ts(486,51): error TS2307: Cannot find module 'jest-diff'.
types/jest/index.d.ts(540,44): error TS2307: Cannot find module 'pretty-format'.

Error: Compilation had errors
    at process.<anonymous> (/home/vsts/work/1/s/node_modules/@definitelytyped/perf/dist/measure/measureBatchCompilationWorker.js:24:19)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
Error: Parsing failed.
    at fail (/home/vsts/work/1/s/node_modules/@definitelytyped/utils/dist/process.js:76:20)
    at ChildProcess.<anonymous> (/home/vsts/work/1/s/node_modules/@definitelytyped/utils/dist/process.js:63:21)
    at ChildProcess.emit (events.js:311:20)
    at finish (internal/child_process.js:861:14)
    at processTicksAndRejections (internal/process/task_queues.js:79:11)

Travis CI build result:

Error: Errors in typescript@3.9 for external dependencies:
../jest/index.d.ts(486,51): error TS2307: Cannot find module 'jest-diff' or its corresponding type declarations.
../jest/index.d.ts(540,44): error TS2307: Cannot find module 'pretty-format' or its corresponding type declarations.
    at /home/travis/build/DefinitelyTyped/DefinitelyTyped/node_modules/dtslint/bin/index.js:195:19
    at Generator.next (<anonymous>)
    at fulfilled (/home/travis/build/DefinitelyTyped/DefinitelyTyped/node_modules/dtslint/bin/index.js:6:58)
Error: The following packages had errors: jest-environment-puppeteer
    at doRunTests (/home/travis/build/DefinitelyTyped/DefinitelyTyped/node_modules/types-publisher/bin/tester/test-runner.js:220:11)
    at process._tickCallback (internal/process/next_tick.js:68:7)

[typescript-bot]

@douglascayers Thank you for submitting this PR!

🔔 @JoshuaKGoldberg @ifiokjr @favna - please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

If no reviewer appears after a week, a DefinitelyTyped maintainer will review the PR instead.

[typescript-bot]

@douglascayers The Travis CI build failed! Please review the logs for more information.

Once you've pushed the fixes, the build will automatically re-run. Thanks!

[douglascayers]

The compile errors are in a separate package, jest, and not related to my changes (as far as I can tell).

If you open https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/jest/index.d.ts locally, you should see two compile errors:

1. line 486 at import("jest-diff").DiffOptions

2. line 540 at import('pretty-format').Plugin

I've come across this stackoverflow question but no answers.

What is the recommended next action considering the issue is due to a package I'm not trying to update??

[typescript-bot]

@douglascayers The Travis CI build failed! Please review the logs for more information.

Once you've pushed the fixes, the build will automatically re-run. Thanks!

[typescript-bot]

@douglascayers The Travis CI build failed! Please review the logs for more information.

Once you've pushed the fixes, the build will automatically re-run. Thanks!

[favna]

LGTM. As for the failing CI, I think that including the dependencies in the package.json list of dependencies will resolve the issue but I'm not 100% sure on that. You can definitely try and run tests locally (npm run test)

[douglascayers]

LGTM. As for the failing CI, I think that including the dependencies in the package.json list of dependencies will resolve the issue but I'm not 100% sure on that. You can definitely try and run tests locally (npm run test)

Unfortunately, updating the package.json file didn't resolve the build issues.

[douglascayers]

LGTM. As for the failing CI, I think that including the dependencies in the package.json list of dependencies will resolve the issue but I'm not 100% sure on that. You can definitely try and run tests locally (npm run test)

After my first attempt didn't work, I recalled that jest-diff and pretty-format are sub-packages of the jest monorepo.

So I then tried again by adding the @jest prefix to the package names:

This led to an interesting different error after running npm run test:

Error: In package.json: Dependency @jest/jest-diff not in whitelist.
If you are depending on another `@types` package, do *not* add it to a `package.json`. Path mapping should make the import work.
For namespaced dependencies you then have to add a `paths` mapping from `@namespace/library` to `namespace__library` in `tsconfig.json`.
If this is an external library that provides typings,  please make a pull request to types-publisher adding it to `dependenciesWhitelist.txt`.
    at checkPackageJsonDependencies (/Users/doug.ayers/Documents/workspace/DefinitelyTyped/node_modules/types-publisher/bin/lib/definition-parser.js:187:19)

Thinking that jest-diff and pretty-format were part of DefinitelyTyped, I started down the route of adding a paths mapping to tsconfig.json according to the first part of the error message:

If you are depending on another @types package, do not add it to a package.json. Path mapping should make the import work.
For namespaced dependencies you then have to add a paths mapping from @namespace/library to namespace__library in tsconfig.json.

Realizing that those packages are in fact not part of DefinitelyTyped, then they must be external. And the next part of the error message had guidance on external dependencies:

If this is an external library that provides typings, please make a pull request to types-publisher adding it to dependenciesWhitelist.txt.

Taking a peek at dependenciesWhitelist.txt, I saw that some other @jest packages were already listed.

I then verified that jest-diff and pretty-format are indeed written in typescript and provide their own typings -- meaning they're not candidates to bring in to DefinitelyTyped.

In conclusion, I've submitted microsoft/types-publisher#769 to add @jest/jest-diff and @jest/pretty-format to the dependencies whitelist. Once that pull request is merged then I'll retest and push up a new commit to update package.json.

[jablko]

Is this a bug in @jest/environment?

$ npm install @jest/environment
$ > index.ts
$ tsc --types @jest/environment index.ts
node_modules/@jest/environment/build/index.d.ts:8:23 - error TS2688: Cannot find type definition file for 'jest'.

8 /// <reference types="jest" />
                        ~~~~

@jest/environment references types="jest" without a dependency on @types/jest.

I don't know why @jest/environment/build/index.d.ts contains /// <reference types="jest" />: I suspect it's unintended. I haven't found an existing issue for this yet.

[jablko]

(You get the jest-diff and pretty-format errors in the automated tests because in that case all @types packages exist but @types/jest's dependencies aren't installed because @jest/environment references types="jest" without a dependency on @types/jest?)

[jablko]

I opened jestjs/jest#9875 to remove the /// <reference types="jest" /> from @jest/environment. If it's accepted then this PR should start passing the automated tests, because @types/jest-environment-puppeteer won't depend on jest-diff/pretty-format (via @jest/environment and @types/jest).

[douglascayers]

Thanks @jablko for the help!

[douglascayers]

🙌 Good news! @jablko's pull request jestjs/jest#9875 got merged into master branch of facebook/jest.

I imagine once they cut a new release (25.4.1+) then we can retry testing this pull request (I think..)

[favna]

@DouglasAntunes Tip: once that's released, other than waiting for staff to retrigger the CI processes, since PRs on this repo are squash and merged anyway you can just trigger it yourself at that time with an empty commit, in CLI: git commit --allow-empty -m "trigger ci" && git push

[typescript-bot]

@douglascayers I haven't seen anything from you in a while and this PR currently has problems that prevent it from being merged. The PR will be closed tomorrow if there aren't new commits to fix the issues.

[favna]

@sandersn this PR is still pending work elsewhere (please read comments above) and should not be closed yet. Can you prevent @typescript-bot from doing so?

[typescript-bot]

@douglascayers To keep things tidy, we have to close PRs that aren't mergeable but don't have activity from their author. No worries, though - please open a new PR if you'd like to continue with this change. Thank you!

[douglascayers]

That's unfortunate that @typescript-bot closed this in-progress pull request

[favna]

@DouglasAntunes I guess just rebase your branch when Jest is updated and recreate the PR sigh

[orta]

oops, sorry about the bot - we added support today to make sure it won't close if maintainers are still chatting DefinitelyTyped/dt-mergebot#33