gc: let feature.experimental imply gc.cruftPacks

This is a small reroll of an adopted version of Emily's series[1], which I saw while sifting through old mail in my inbox.

This is substantively unchanged from the previous round, save:

- renaming the helper functions which assert and refute the existence of cruft packs, and

- an additional test which ensures that we can opt out of cruft packs via config

A range-diff is included below for convenience.

Thanks in advance for your review.

[1]: https://lore.kernel.org/git/[email protected]/

Emily Shaffer (2):
gc: add tests for --cruft and friends
config: let feature.experimental imply gc.cruftPacks=true

 Documentation/config/feature.txt |  3 +
 builtin/gc.c                     |  7 ++-
 repo-settings.c                  |  1 +
 repository.h                     |  1 +
 t/t6500-gc.sh                    | 96 ++++++++++++++++++++++++++++++++
 5 files changed, 106 insertions(+), 2 deletions(-)

Range-diff against v2:
1: 35d2c97715 ! 1: e8726f3de7 gc: add tests for --cruft and friends

    @@ t/t6500-gc.sh: test_expect_success 'one of gc.reflogExpire{Unreachable,}=never d
     +	git reset HEAD^^
     +}
     +
    -+assert_cruft_pack_exists () {
    ++assert_cruft_packs () {
     +	find .git/objects/pack -name "*.mtimes" >mtimes &&
     +	sed -e 's/\.mtimes$/\.pack/g' mtimes >packs &&
     +
    @@ t/t6500-gc.sh: test_expect_success 'one of gc.reflogExpire{Unreachable,}=never d
     +
     +		prepare_cruft_history &&
     +		git gc --cruft &&
    -+		assert_cruft_pack_exists
    ++		assert_cruft_packs
     +	)
     +'
     +
    @@ t/t6500-gc.sh: test_expect_success 'one of gc.reflogExpire{Unreachable,}=never d
     +
     +		prepare_cruft_history &&
     +		git -c gc.cruftPacks=true gc &&
    -+		assert_cruft_pack_exists
    ++		assert_cruft_packs
     +	)
     +'
     +
2:  eb151752b8 ! 2:  13a25a425b config: let feature.experimental imply gc.cruftPacks=true
    @@ repository.h: struct repo_settings {
      	int sparse_index;
     
      ## t/t6500-gc.sh ##
    -@@ t/t6500-gc.sh: assert_cruft_pack_exists () {
    +@@ t/t6500-gc.sh: assert_cruft_packs () {
      	done <packs
      }
      
    -+refute_cruft_packs_exist () {
    ++assert_no_cruft_packs () {
     +	find .git/objects/pack -name "*.mtimes" >mtimes &&
     +	test_must_be_empty mtimes
     +}
    @@ t/t6500-gc.sh: test_expect_success 'gc.cruftPacks=true generates a cruft pack' '
     +
     +		prepare_cruft_history &&
     +		git -c feature.experimental=true gc &&
    -+		assert_cruft_pack_exists
    ++		assert_cruft_packs
     +	)
     +'
     +
    @@ t/t6500-gc.sh: test_expect_success 'gc.cruftPacks=true generates a cruft pack' '
     +
     +		prepare_cruft_history &&
     +		git -c gc.cruftPacks=true -c feature.experimental=false gc &&
    -+		assert_cruft_pack_exists
    ++		assert_cruft_packs
    ++	)
    ++'
    ++
    ++test_expect_success 'feature.experimental=true can be overridden' '
    ++	git init crufts &&
    ++	test_when_finished "rm -fr crufts" &&
    ++	(
    ++		cd crufts &&
    ++
    ++		prepare_cruft_history &&
    ++		git -c feature.expiremental=true -c gc.cruftPacks=false gc &&
    ++		assert_no_cruft_packs
     +	)
     +'
     +
    @@ t/t6500-gc.sh: test_expect_success 'gc.cruftPacks=true generates a cruft pack' '
     +
     +		prepare_cruft_history &&
     +		git -c feature.experimental=false gc &&
    -+		refute_cruft_packs_exist
    ++		assert_no_cruft_packs
     +	)
     +'
     +

2.38.0.16.g393fd4c6db