From: Phillip Wood Date: Tue, 08 Nov 2022 09:58:49 GMT Subject: Re: [PATCH v2] rebase --update-refs: avoid unintended ref deletion Message-ID: <934a0862-2713-7705-9155-6584449397c7@dunelm.org.uk> In-Reply-To: <20221107174752.91186-1-vdye@github.com> Hi Victoria On 07/11/2022 17:47, Victoria Dye wrote: > In b3b1a21d1a5 (sequencer: rewrite update-refs as user edits todo list, > 2022-07-19), the 'todo_list_filter_update_refs()' step was added to handle > the removal of 'update-ref' lines from a 'rebase-todo'. Specifically, it > removes potential ref updates from the "update refs state" if a ref does not > have a corresponding 'update-ref' line. > > However, because 'write_update_refs_state()' will not update the state if > the 'refs_to_oids' list was empty, removing *all* 'update-ref' lines will > result in the state remaining unchanged from how it was initialized (with > all refs' "after" OID being null). Then, when the ref update is applied, all > refs will be updated to null and consequently deleted. > > To fix this, delete the 'update-refs' state file when 'refs_to_oids' is > empty. Additionally, add a tests covering "all update-ref lines removed" > cases. Thanks for re-rolling, unsurprisingly I prefer the unlink() approach to the previous version. As Stolee said the test coverage looks good too. Best Wishes Phillip > Reported-by: herr.kaste > Helped-by: Phillip Wood > Helped-by: Derrick Stolee > Signed-off-by: Victoria Dye > --- > Changes since v1: > - Modified approach to handling empty 'refs_to_oids' from "optional force write > empty file" to "always unlink" > - Added/updated tests > > sequencer.c | 9 ++- > t/t3404-rebase-interactive.sh | 107 ++++++++++++++++++++++++++++++++++ > 2 files changed, 113 insertions(+), 3 deletions(-) > > diff --git a/sequencer.c b/sequencer.c > index e658df7e8ff..798a9702961 100644 > --- a/sequencer.c > +++ b/sequencer.c > @@ -4130,11 +4130,14 @@ static int write_update_refs_state(struct string_list *refs_to_oids) > struct string_list_item *item; > char *path; > > - if (!refs_to_oids->nr) > - return 0; > - > path = rebase_path_update_refs(the_repository->gitdir); > > + if (!refs_to_oids->nr) { > + if (unlink(path) && errno != ENOENT) > + result = error_errno(_("could not unlink: %s"), path); > + goto cleanup; > + } > + > if (safe_create_leading_directories(path)) { > result = error(_("unable to create leading directories of %s"), > path); > diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh > index 4f5abb5ad25..462cefd25df 100755 > --- a/t/t3404-rebase-interactive.sh > +++ b/t/t3404-rebase-interactive.sh > @@ -1964,6 +1964,113 @@ test_expect_success 'respect user edits to update-ref steps' ' > test_cmp_rev HEAD refs/heads/no-conflict-branch > ' > > +test_expect_success '--update-refs: all update-ref lines removed' ' > + git checkout -b test-refs-not-removed no-conflict-branch && > + git branch -f base HEAD~4 && > + git branch -f first HEAD~3 && > + git branch -f second HEAD~3 && > + git branch -f third HEAD~1 && > + git branch -f tip && > + > + test_commit test-refs-not-removed && > + git commit --amend --fixup first && > + > + git rev-parse first second third tip no-conflict-branch >expect-oids && > + > + ( > + set_cat_todo_editor && > + test_must_fail git rebase -i --update-refs base >todo.raw && > + sed -e "/^update-ref/d" todo > + ) && > + ( > + set_replace_editor todo && > + git rebase -i --update-refs base > + ) && > + > + # Ensure refs are not deleted and their OIDs have not changed > + git rev-parse first second third tip no-conflict-branch >actual-oids && > + test_cmp expect-oids actual-oids > +' > + > +test_expect_success '--update-refs: all update-ref lines removed, then some re-added' ' > + git checkout -b test-refs-not-removed2 no-conflict-branch && > + git branch -f base HEAD~4 && > + git branch -f first HEAD~3 && > + git branch -f second HEAD~3 && > + git branch -f third HEAD~1 && > + git branch -f tip && > + > + test_commit test-refs-not-removed2 && > + git commit --amend --fixup first && > + > + git rev-parse first second third >expect-oids && > + > + ( > + set_cat_todo_editor && > + test_must_fail git rebase -i \ > + --autosquash --update-refs \ > + base >todo.raw && > + sed -e "/^update-ref/d" todo > + ) && > + > + # Add a break to the end of the todo so we can edit later > + echo "break" >>todo && > + > + ( > + set_replace_editor todo && > + git rebase -i --autosquash --update-refs base && > + echo "update-ref refs/heads/tip" >todo && > + git rebase --edit-todo && > + git rebase --continue > + ) && > + > + # Ensure first/second/third are unchanged, but tip is updated > + git rev-parse first second third >actual-oids && > + test_cmp expect-oids actual-oids && > + test_cmp_rev HEAD tip > +' > + > +test_expect_success '--update-refs: --edit-todo with no update-ref lines' ' > + git checkout -b test-refs-not-removed3 no-conflict-branch && > + git branch -f base HEAD~4 && > + git branch -f first HEAD~3 && > + git branch -f second HEAD~3 && > + git branch -f third HEAD~1 && > + git branch -f tip && > + > + test_commit test-refs-not-removed3 && > + git commit --amend --fixup first && > + > + git rev-parse first second third tip no-conflict-branch >expect-oids && > + > + ( > + set_cat_todo_editor && > + test_must_fail git rebase -i \ > + --autosquash --update-refs \ > + base >todo.raw && > + sed -e "/^update-ref/d" todo > + ) && > + > + # Add a break to the beginning of the todo so we can resume with no > + # update-ref lines > + echo "break" >todo.new && > + cat todo >>todo.new && > + > + ( > + set_replace_editor todo.new && > + git rebase -i --autosquash --update-refs base && > + > + # Make no changes when editing so update-refs is still empty > + cat todo >todo.new && > + git rebase --edit-todo && > + git rebase --continue > + ) && > + > + # Ensure refs are not deleted and their OIDs have not changed > + git rev-parse first second third tip no-conflict-branch >actual-oids && > + test_cmp expect-oids actual-oids > +' > + > test_expect_success '--update-refs: check failed ref update' ' > git checkout -B update-refs-error no-conflict-branch && > git branch -f base HEAD~4 && > -- > 2.38.0 >