Re: [PATCH] t1092: use GIT_PROGRESS_DELAY for consistent results

Derrick Stolee [off-list ref] writes:

The test is comparing the same exact Git command just with
different configurations. Any change to what Git writes to
stderr should be consistent across these, unless there is
an explicit reason why it would behave differently across
these options (for example, saying "You are in a sparse
checkout" in 'git status').

There are no expectations that stderr is stable across
versions of Git. These tests don't add friction to developers
making new features or changing the error messages that appear
over stderr. It's just that these tests should catch any
unintended inconsistency across these modes.

If it just happens that an auto-gc gets triggered, and millions of
other similar reasons in the future, will break that expectation,
without running two different vintages of Git.

I agree with Jonathan that it fundamentally is flakey to expect two
invocations of Git will behave exactly the same.  Even repacking a
repository starting from exactly the same state into a single pack
may not produce byte-for-byte identical result due to thread
scheduling.