Various unit tests: Increase coverage

[ferdnyc]

Update: I'm an idiot. The failure was due to the short duration, and the fact that there were only 120 frames available in the reader at the specified frame rate. (Though, interestingly, that doesn't throw an OutOfBoundsFrame it seems.)

As it says, this PR is a work-in-progress. Not because it's unfinished, but because a test is failing.

I decided to replace the first test (which had a catch in it that was screwing up the test coverage) with a simple no-op test: Create a mapping from 24fps to 24fps with no pulldown. Then read its Name() (adds an extra line of coverage), and finally read one frame from it. So, it just gets the same frame back. (When you use the right duration.)

Unfortunately, the test fails, and gets back frame 120 for original frame 125.
That seems bad.

Edit: Added a JSON test that just reads the Json() string from the mapper, then SetJson()s it back again (and spot-checks that things haven't changed.) That really raised the test coverage; I may do that for the other classes as well.

[codecov]

Codecov Report

Merging #586 into develop will increase coverage by 2.37%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop     #586      +/-   ##
===========================================
+ Coverage    49.90%   52.28%   +2.37%     
===========================================
  Files          132      131       -1     
  Lines        10686    10761      +75     
===========================================
+ Hits          5333     5626     +293     
+ Misses        5353     5135     -218     

Impacted Files	Coverage Δ
tests/Color_Tests.cpp	100.00% <100.00%> (ø)
tests/FrameMapper_Tests.cpp	100.00% <100.00%> (+0.92%)	⬆️
tests/Point_Tests.cpp	100.00% <100.00%> (ø)
examples/qt-demo/main.cpp
src/FrameMapper.cpp	91.41% <0.00%> (+4.04%)	⬆️
src/Exceptions.h	29.85% <0.00%> (+4.47%)	⬆️
src/KeyFrame.cpp	85.94% <0.00%> (+5.22%)	⬆️
src/Json.cpp	100.00% <0.00%> (+9.09%)	⬆️
src/Coordinate.cpp	66.66% <0.00%> (+47.61%)	⬆️
... and 3 more

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[jonoomph]

LGTM!

[jonoomph]

Merge when ready!

[ferdnyc]

I think I've run out of steam on this one for now. Just made a change to codecov.yml to hopefully get /examples out of the coverage report, and assuming that passes I'll merge. Coverage up from 49.90% (possibly higher, albeit artificially, if that config change takes), and newly 100% in three different files. I'd say that's a reasonable bump for one sortie.

[ferdnyc]

(My attempt to exclude examples/ was... well, honestly, I'm not sure if it was successful.)

The two files that get built into targets by CMake still show up in the list, but Codecov doesn't seem to be counting any of their source lines for coverage purposes, which I guess is what really matters. Was hoping to get them off the list entirely, but meh...