bottle: add tests for writing part

[iMichka]

In preparation for #9315

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew tests with your changes locally?
• Have you successfully run brew man locally and committed any changes?

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[BrewTestBot]

Review period will end on 2020-12-10 at 22:06:30 UTC.

[iMichka]

@SeekingMeaning this will conflict with your changes in #9095. I would like to get my changes in first, so I can proceed on working on the next steps for #9315. The pattern refactoring can then come as a second step.

[iMichka]

Just if someone wonders: I struggled with the flush/closes of the files. The current code was the only way I found to make it work.

[MikeMcQuaid]

This refactoring is now very hard to review.

I'm afraid I just don't have confidence that this isn't going to break code that's very important and widely used to "improve readability" in a way that I don't think actually does improve readability. I worry that it's only more readable to you @iMichka now because you're the one who has refactored it.

For changes like this what I'd propose is:

1. open a PR that adds tests to cover 100% of the existing code you wish to refactor and makes no modifications to the existing code. This will demonstrate the tests exercise (at least some) of the existing functionality.
2. open a PR that refactors the existing code and makes no modifications to the tests. This will demonstrate that the refactor does not change (at least some) of the existing functionality.
3. additional, small PRs can be made that add more tests and refactor without needing to alter existing tests.

Sorry to do this, I've just seen these refactorings usually break things (sometimes in ways that aren't apparent until months down the line).

[MikeMcQuaid]

@SeekingMeaning this will conflict with your changes in #9095. I would like to get my changes in first, so I can proceed on working on the next steps for #9315. The pattern refactoring can then come as a second step.

I would like #9095 to land before this as it's fixing a problem that keeps reoccurring whereas this PR does not in itself do anything beyond refactoring code.

[BrewTestBot]

Review period ended.

[iMichka]

@MikeMcQuaid I tried a different strategy. Can you have a quick look to validated the approach before I add more tests?

• I know that brew style is failing, but I do not know how to fix all of the errors. I might need help here.
• I have no clue what is going on with the indentation in the EOS blocks ... the output needs to look that weird to make the test pass ...

[MikeMcQuaid]

Looking great, thanks for the changes @iMichka! This will definitely provide more confidence while refactoring here 👏🏻

[iMichka]

The test is passing now, but I can't make brew style pass. Either brew style, either the test is fine. I can't make both work together ...

[iMichka]

This should work now. Thanks @SeekingMeaning for the test fix!

[iMichka]

Merged, CI is green. I have one or two more tests to test other branches of that part of the code, this should be straightforward now and I will open a new PR for that.

[MikeMcQuaid]

Thanks for persevering @iMichka!