feat: collect coverage of end-to-end tests

[mxschmitt]

TODOs:

• add comment for documentation in global d.ts what saveCoverage does
• add documentation in README: required following babel plugin: https://www.npmjs.com/package/babel-plugin-istanbul
• clarify with @mmarkelov if loading the config like I did in PlaywrightRunner.runTests is okay

Example usage here: playwright-community/playwright-jest-examples#8

Will look like that if you are using the example:

[github-actions]

Pull Request Test Coverage Report for Build 141857263

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 95.238%

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Totals
Change from base Build 141220261:	0.0%
Covered Lines:	71
Relevant Lines:	72

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💛 - Coveralls

[mmarkelov]

@mxschmitt that's a really nice new feature. But maybe we should put it in separate package and make it optional?

[mxschmitt]

@mxschmitt that's a really nice new feature. But maybe we should put it in separate package and make it optional?

Unfortunately it needs a tight integrations in before all tests and after all tests hooks. That's why I think it does not make so much sense and would decrease the user experience for that significantly. As a pitfall it adds a few more dependencies, but shouldn't be a big deal in my mind.

[mxschmitt]

Let me know if they are any other issues before we can merge it. Thanks! 👍

[mmarkelov]

Let me know if they are any other issues before we can merge it. Thanks! 👍

I think we are ready to merge it