The `io_blendfile_versioning` test is currently one of the slowest
(excluding Cycles ones) in debug builds, it can easily take several
minutes to complete.
This commit split it into several instances, each processing a subset of
all the blendfiles.
This gives a strong speed-up when only running that specific test.
As expected, speedup is neglectable when running the whole test suite
though.
| instances | debug | release | debug all* | release all |
| --------- | ------ | ------- | ---------- | ----------- |
| 1 | 190.95 | 19.39 | 439.54 | 63.51 |
| 4 | 61.80 | 6.81 | N/A | N/A |
| 8 | 38.33 | 5.14 | 435.00 | 58.93 |
| 16 | 33.97 | 4.16 | N/A | N/A |
| 32 | 46.54 | 5.14 | N/A | N/A |
Times are in seconds.
`instances` are the number of tests generated (1 is same as before this
commit).
The first two columns are timings for running the versioning test only,
the last two are timings for the full test suite (excluding Cycles tests
in the debug build case).
3c14067ecd