Complete coverage for branching.py

[edoyango]

This covers the last handful of statements that were not or partially covered.

• I marked a partially covered if statement as no cover since the false case is never reached.
• I pulled out the check_if_index tmp function to make it easier to test.

[coveralls]

Pull Request Test Coverage Report for Build 19347476561

Details

• 28 of 28 (100.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 62.314%

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Totals
Change from base Build 19330227731:	0.1%
Covered Lines:	9811
Relevant Lines:	15342

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💛 - Coveralls

[edoyango]

ok these tests were pretty tricky for me so i'm just a bit demoralized that total coverage has only gone up 0.1% 🥲

[tennlee]

Yeah it's hard! I have the same feeling - I enjoy the big wins a lot more than the little gains (in terms of % covered) but often it's the niggly specific things which are actually more essential. Branching is a really core part of how the pipelines work, and is tricky, so I super-appreciate it. Also, PET has a lot of lines of code, so even a big change is still going to be like 0.3% or something.

[tennlee]

Thanks! Looks great! Much appreciated, great to get the test coverage.