From be19c5ca3e28cb16d55623de2e5aa1d45bd5b5ba Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Wed, 21 Jul 2021 01:42:17 +0000 Subject: [PATCH] t7601: test interaction of merge/rebase/fast-forward flags and options The interaction of rebase and merge flags and options was not well tested. Add several tests to check for correct behavior from the following rules: * --ff-only vs. --[no-]rebase (and the related pull.ff=only vs. pull.rebase) * --rebase[=!false] vs. --no-ff and --ff (and the related pull.rebase=!false overrides pull.ff=!only) * command line flags take precedence over config, except: * --no-rebase heeds pull.ff=!only * pull.rebase=!false vs --no-ff and --ff For more details behind these rules and a larger table of individual cases, refer to https://lore.kernel.org/git/xmqqwnpqot4m.fsf@gitster.g/ and the links found therein. Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- t/t7601-merge-pull-config.sh | 182 +++++++++++++++++++++++++++++++++++ 1 file changed, 182 insertions(+) diff --git a/t/t7601-merge-pull-config.sh b/t/t7601-merge-pull-config.sh index 52e8ccc933..a44e6e69f2 100755 --- a/t/t7601-merge-pull-config.sh +++ b/t/t7601-merge-pull-config.sh @@ -143,6 +143,188 @@ test_expect_success 'pull.rebase not set and --ff-only given (not-fast-forward)' test_i18ngrep ! "Pulling without specifying how to reconcile" err ' +test_does_rebase () { + git reset --hard c2 && + git "$@" . c1 && + # Check that we actually did a rebase + git rev-list --count HEAD >actual && + git rev-list --merges --count HEAD >>actual && + test_write_lines 3 0 >expect && + test_cmp expect actual && + rm actual expect +} + +# Prefers merge over fast-forward +test_does_merge_when_ff_possible () { + git reset --hard c0 && + git "$@" . c1 && + # Check that we actually did a merge + git rev-list --count HEAD >actual && + git rev-list --merges --count HEAD >>actual && + test_write_lines 3 1 >expect && + test_cmp expect actual && + rm actual expect +} + +# Prefers fast-forward over merge or rebase +test_does_fast_forward () { + git reset --hard c0 && + git "$@" . c1 && + + # Check that we did not get any merges + git rev-list --count HEAD >actual && + git rev-list --merges --count HEAD >>actual && + test_write_lines 2 0 >expect && + test_cmp expect actual && + + # Check that we ended up at c1 + git rev-parse HEAD >actual && + git rev-parse c1^{commit} >expect && + test_cmp actual expect && + + # Remove temporary files + rm actual expect +} + +# Doesn't fail when fast-forward not possible; does a merge +test_falls_back_to_full_merge () { + git reset --hard c2 && + git "$@" . c1 && + # Check that we actually did a merge + git rev-list --count HEAD >actual && + git rev-list --merges --count HEAD >>actual && + test_write_lines 4 1 >expect && + test_cmp expect actual && + rm actual expect +} + +# Attempts fast forward, which is impossible, and bails +test_attempts_fast_forward () { + git reset --hard c2 && + test_must_fail git "$@" . c1 2>err && + test_i18ngrep "Not possible to fast-forward, aborting" err +} + +# +# Group 1: Interaction of --ff-only with --[no-]rebase +# (And related interaction of pull.ff=only with pull.rebase) +# +test_expect_failure '--ff-only overrides --rebase' ' + test_attempts_fast_forward pull --rebase --ff-only +' + +test_expect_failure '--ff-only overrides --rebase even if first' ' + test_attempts_fast_forward pull --ff-only --rebase +' + +test_expect_success '--ff-only overrides --no-rebase' ' + test_attempts_fast_forward pull --ff-only --no-rebase +' + +test_expect_failure 'pull.ff=only overrides pull.rebase=true' ' + test_attempts_fast_forward -c pull.ff=only -c pull.rebase=true pull +' + +test_expect_success 'pull.ff=only overrides pull.rebase=false' ' + test_attempts_fast_forward -c pull.ff=only -c pull.rebase=false pull +' + +# Group 2: --rebase=[!false] overrides --no-ff and --ff +# (And related interaction of pull.rebase=!false and pull.ff=!only) +test_expect_success '--rebase overrides --no-ff' ' + test_does_rebase pull --rebase --no-ff +' + +test_expect_success '--rebase overrides --ff' ' + test_does_rebase pull --rebase --ff +' + +test_expect_success '--rebase fast-forwards when possible' ' + test_does_fast_forward pull --rebase --ff +' + +test_expect_success 'pull.rebase=true overrides pull.ff=false' ' + test_does_rebase -c pull.rebase=true -c pull.ff=false pull +' + +test_expect_success 'pull.rebase=true overrides pull.ff=true' ' + test_does_rebase -c pull.rebase=true -c pull.ff=true pull +' + +# Group 3: command line flags take precedence over config +test_expect_failure '--ff-only takes precedence over pull.rebase=true' ' + test_attempts_fast_forward -c pull.rebase=true pull --ff-only +' + +test_expect_success '--ff-only takes precedence over pull.rebase=false' ' + test_attempts_fast_forward -c pull.rebase=false pull --ff-only +' + +test_expect_failure '--no-rebase takes precedence over pull.ff=only' ' + test_falls_back_to_full_merge -c pull.ff=only pull --no-rebase +' + +test_expect_success '--rebase takes precedence over pull.ff=only' ' + test_does_rebase -c pull.ff=only pull --rebase +' + +test_expect_success '--rebase overrides pull.ff=true' ' + test_does_rebase -c pull.ff=true pull --rebase +' + +test_expect_success '--rebase overrides pull.ff=false' ' + test_does_rebase -c pull.ff=false pull --rebase +' + +test_expect_success '--rebase overrides pull.ff unset' ' + test_does_rebase pull --rebase +' + +# Group 4: --no-rebase heeds pull.ff=!only or explict --ff or --no-ff + +test_expect_success '--no-rebase works with --no-ff' ' + test_does_merge_when_ff_possible pull --no-rebase --no-ff +' + +test_expect_success '--no-rebase works with --ff' ' + test_does_fast_forward pull --no-rebase --ff +' + +test_expect_success '--no-rebase does ff if pull.ff unset' ' + test_does_fast_forward pull --no-rebase +' + +test_expect_success '--no-rebase heeds pull.ff=true' ' + test_does_fast_forward -c pull.ff=true pull --no-rebase +' + +test_expect_success '--no-rebase heeds pull.ff=false' ' + test_does_merge_when_ff_possible -c pull.ff=false pull --no-rebase +' + +# Group 5: pull.rebase=!false in combination with --no-ff or --ff +test_expect_success 'pull.rebase=true and --no-ff' ' + test_does_rebase -c pull.rebase=true pull --no-ff +' + +test_expect_success 'pull.rebase=true and --ff' ' + test_does_rebase -c pull.rebase=true pull --ff +' + +test_expect_success 'pull.rebase=false and --no-ff' ' + test_does_merge_when_ff_possible -c pull.rebase=false pull --no-ff +' + +test_expect_success 'pull.rebase=false and --ff, ff possible' ' + test_does_fast_forward -c pull.rebase=false pull --ff +' + +test_expect_success 'pull.rebase=false and --ff, ff not possible' ' + test_falls_back_to_full_merge -c pull.rebase=false pull --ff +' + +# End of groupings for conflicting merge vs. rebase flags/options + test_expect_success 'merge c1 with c2' ' git reset --hard c1 && test -f c0.c &&