Postprocessing frame check bug fix

[gpucce]

PR Checklist

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• Did I update CHANGELOG.md with whatever changes/features I added with this PR?
• Did I make sure to only change the part of the file where I introduced a new change/feature?
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Link to relevant issue(s)
Closes #

How did you address these issues with this PR? What methods did you use?
The check for frames returned by postprocess_frames_flow was wrongly written, this should fix it.

[codecov]

Codecov Report

Merging #431 (2695819) into master (5781699) will not change coverage.
The diff coverage is 100.00%.

❗ Current head 2695819 differs from pull request most recent head e9bd758. Consider uploading reports for the commit e9bd758 to get more accurate results

@@           Coverage Diff           @@
##           master     #431   +/-   ##
=======================================
  Coverage   96.19%   96.19%           
=======================================
  Files          36       36           
  Lines        1604     1604           
=======================================
  Hits         1543     1543           
  Misses         61       61           

Impacted Files	Coverage Δ
src/Javis.jl	96.03% <100.00%> (ø)

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[Wikunia]

I don't know how the previous code could result in a failure. Probably missing something here. Aren't the frames always from 1-... ? Isn't gif rendering would fail otherwise? Maybe add a test which would fail in the current version and is fixed by this.

Btw make sure to update your personal fork before creating a PR. (For the next one don't worry about this one) as currently this PR has >30 commits but only the last is the one which isn't merged already

[gpucce]

Sorry for merging I though I did.

The error was this, I think for javis is not an issue having for example frame 0 defined but with the old solution this would throw this error instead of using frame 0 normally, now it shouldn't anymore.

I think it throws a warning but does not fail with frame 0 at least. Anyway even if it would fail anyway it is still better to have the regular error instead of this one that would be unexplicative.

I will check again and add the test later today!

[gpucce]

So I adapted a test in postprocessing to account for the negative frames and it does work with this PR while it does not without it.

[Wikunia]

Great thanks

[Wikunia]

Thanks LGTM. Please add a line to the changelog :)
Then I'll merge and tag a new release

[gpucce]

That should be it!