From: Phillip Wood Date: Thu, 01 Oct 2026 15:48:35 GMT Subject: Re: [PATCH v3] t5520: don't expire reflogs where it matters Message-ID: <667a68a1-641f-46c4-a718-8dd81d5c219f@gmail.com> In-Reply-To: Hi Thomas This looks good. Thanks for the patch and also your help finding where the difference in reflog entry count was coming from - before your mail, I did not realize that "git merge" stashed changes without "--autostash". Phillip On 01/10/2026 09:24, Thomas Bachem via GitGitGadget wrote: > From: Thomas Bachem > > "git merge" saves any uncommitted changes with "git stash" before it > tries a merge strategy. When the strategy does not handle the merge, > it restores them with "git stash apply --index". If some of the > changes are staged, that runs "git reset", which writes an entry to > the reflog of HEAD. The tests that pull with autostash disabled run > eight such merges, each with a new file staged. > > An upcoming change makes "git stash apply --index" merge the index > in-core, so it no longer runs "git reset" and those entries go away. > Another makes the default "merge" backend of "git rebase" run auto > maintenance when it finishes. Together, they change when auto > maintenance expires the reflogs. > > This means that unfortunately the reflogs are expired at the end of > "git pull --rebase" in the "--rebase with rebased upstream" test. The > "git pull --rebase -f" in the next test looks for the fork point in > the reflog of refs/remotes/me/copy, but as the test suite dates every > reflog entry to 2005, the expiry has emptied that reflog. Pull then > finds no fork point, so the rebase also replays copy-orig, the commit > "copy" was rewound from, and it conflicts. > > Disable reflog expiration in this script, as ea7d894f44 (t34xx: don't > expire reflogs where it matters, 2026-02-24) did for the rebase tests, > so that the test no longer depends on where the expiry falls. > > Reported-by: Junio C Hamano > Helped-by: D. Ben Knoble > Helped-by: Phillip Wood > Assisted-by: Claude Fable 5.1 > Signed-off-by: Thomas Bachem > --- > t5520: don't expire reflogs where it matters > > The t5520 failure Junio saw in 'seen' with Ben Knoble's stash series, > bisected by Ben to tb/rerere-lock-grace and taken apart in the thread: > https://lore.kernel.org/git/a59c4225-f093-4001-b77a-2083dfecce6e@gmail.com/ > > Changes since v2: only the commit message. I had the eight merges in the > wrong tests: they come from the pulls with autostash disabled, where > "git merge" stashes and restores the staged file itself. I also dropped > the clause about the hundred entries and took Phillip's opening for the > third paragraph, all from his review: > https://lore.kernel.org/git/8b81c508-ac67-498d-b78f-a4b5dab8c198@gmail.com/ > > Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-2243%2Fthomasbachem%2Ft5520-reflog-expire-v3 > Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-2243/thomasbachem/t5520-reflog-expire-v3 > Pull-Request: https://github.com/gitgitgadget/git/pull/2243 > > Range-diff vs v2: > > 1: 6699f3782e ! 1: be6c3f21c5 t5520: don't expire reflogs where it matters > @@ Commit message > tries a merge strategy. When the strategy does not handle the merge, > it restores them with "git stash apply --index". If some of the > changes are staged, that runs "git reset", which writes an entry to > - the reflog of HEAD. The autostash tests in this script run eight such > - merges. > + the reflog of HEAD. The tests that pull with autostash disabled run > + eight such merges, each with a new file staged. > > An upcoming change makes "git stash apply --index" merge the index > in-core, so it no longer runs "git reset" and those entries go away. > Another makes the default "merge" backend of "git rebase" run auto > maintenance when it finishes. Together, they change when auto > - maintenance expires all reflogs, which it does once a hundred entries > - in the reflog of HEAD are due to expire. > + maintenance expires the reflogs. > > - With both, the expiry comes at the end of the "git pull --rebase" in > - the "--rebase with rebased upstream" test. The "git pull --rebase -f" > - in the next test looks for the fork point in the reflog of > - refs/remotes/me/copy, but as the test suite dates every reflog entry > - to 2005, the expiry has emptied that reflog. Pull then finds no fork > - point, so the rebase also replays copy-orig, the commit "copy" was > - rewound from, and it conflicts. > + This means that unfortunately the reflogs are expired at the end of > + "git pull --rebase" in the "--rebase with rebased upstream" test. The > + "git pull --rebase -f" in the next test looks for the fork point in > + the reflog of refs/remotes/me/copy, but as the test suite dates every > + reflog entry to 2005, the expiry has emptied that reflog. Pull then > + finds no fork point, so the rebase also replays copy-orig, the commit > + "copy" was rewound from, and it conflicts. > > Disable reflog expiration in this script, as ea7d894f44 (t34xx: don't > expire reflogs where it matters, 2026-02-24) did for the rebase tests, > > > t/t5520-pull.sh | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/t/t5520-pull.sh b/t/t5520-pull.sh > index 27f38ab3c8..bc818605a5 100755 > --- a/t/t5520-pull.sh > +++ b/t/t5520-pull.sh > @@ -35,6 +35,12 @@ test_pull_autostash_fail () { > } > > test_expect_success setup ' > + # Commit dates are hardcoded to 2005, and the reflog entries will have > + # a matching timestamp. Maintenance may thus immediately expire > + # reflogs if it was running. > + git config set gc.reflogExpire never && > + git config set gc.reflogExpireUnreachable never && > + > echo file >file && > git add file && > git commit -a -m original > > base-commit: 34f06850c16c7f7ac822b1adc71354f11b0f2ca3