fix: do not overwrite coverage after each test suite

[joe223]

Ref #20
Example https://github.com/joe223/tiny-swiper/blob/f0acd38d76a9a23a3ddcf5cabca8d5f4d37c633c/package.json#L28

[coveralls]

Pull Request Test Coverage Report for Build 133

• 34 of 34 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-5.7%) to 94.286%

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Totals
Change from base Build 131:	-5.7%
Covered Lines:	107
Relevant Lines:	115

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💛 - Coveralls

[Perronef5]

Can we get this merged? These changes would really help me with my coverage.

[rafael-leal-mccormack]

I would also appreciate it if this got merged, it could possibly solve our problem

[bcoe]

@joe223 @Perronef5 @rafael-leal-mccormack, if I'm understanding the problem, each test suite overwrites the coverage information, so it's difficult to collect coverage for a full run?

sorry that this library has seen so little love, as it turns out I just don't do a ton of front end coding 😄 I will do my best to land some of the fixes that are submitted, and would be very happy to accept more help on this library.

[joe223]

@joe223 @Perronef5 @rafael-leal-mccormack, if I'm understanding the problem, each test suite overwrites the coverage information, so it's difficult to collect coverage for a full run?

@bcoe Yep, Each test suit will overwrites the coverage information, we only can get the last test suit data, I merged all test suit information in this PR to avoid data-overwriting.

[bcoe]

@joe223 @Perronef5 @SanterreJo this is now staged on the next tag on npm, you can try things out by running:

npm i puppeteer-to-istanbul@next.

Let me know if you bump into any issues. Note, I've also set up an automated release pipeline, so that we can hopefully have a faster turnaround in the future.