fix: add placeholder to fix Implicit Else

[adrian-burlacu-software]

@bcoe
While implicit else reporting was fixed in pull #663, it no longer aligns to the instrumented API. Where I previously updated that to provide a placeholder in pull #633, by now the placeholder is gone.

This became an issue #670

The simplest was to update the reporting to reflect this change in the instrumenter API. Namely, I added a placeholder into the metadata array when the single if branch with no else condition.

I'd fix the design but that's already taking hours to reason about the various fails I could cause.

[bcoe]

I left a couple questions, thanks for the patch.

[bcoe]

@adrian-burlacu-software what's the state of this PR? I'm hesitant to land if it requires that we modify an existing regression test. But, since you wrote the regression test, you'd know better than me whether we should land.

[adrian-burlacu-software]

@adrian-burlacu-software what's the state of this PR? I'm hesitant to land if it requires that we modify an existing regression test. But, since you wrote the regression test, you'd know better than me whether we should land.

@bcoe
I took another look at the files from pull #663 to resolve issue #649. It looks like I left out this placeholder in the test back then, meaning this should get landed.

The novelty for this level of integrity (with testing) to the project and the novelty of the project to me are the main problems here. Feels like some KISS design & testing would help, the Fast-Fuzz tool can now test entire projects, has been tested in practice, and I don't plan on making any more changes to it this year: https://www.npmjs.com/package/fast-fuzz