Re: [PATCH] rebase: apply and cleanup autostash when rebase fails to start
- From
- Phillip Wood <phillip.wood123@gmail.com>
- Date
- Aug 14, 2024, 15:59 UTC
- Message-ID
- <b676bd17-1cc8-4639-acb7-675dde32a1ae@gmail.com>
- In-Reply-To
- <ZrzA0yp45w9NuTp2@tanuki>
Hi Patrick
On 14/08/2024 15:36, Patrick Steinhardt wrote:
Show 15 quoted lines
> On Wed, Aug 14, 2024 at 01:22:27PM +0000, Phillip Wood via GitGitGadget wrote: >> From: Phillip Wood <phillip.wood@dunelm.org.uk> >> >> If "git rebase" fails to start after stashing the user's uncommitted >> changes then it forgets to restore the stashed changes and remove state > > s/remove/& the/ > >> directory. To make matters worse running "git rebase --abort" to apply > > s/worse/&,/ > >> the stashed changes and cleanup the state directory fails because the > > s/cleanup/& of/
Thanks for catching those typos
Show 23 quoted lines
>> diff --git a/builtin/rebase.c b/builtin/rebase.c
>> index e3a8e74cfc2..ac23c4ddbb0 100644
>> --- a/builtin/rebase.c
>> +++ b/builtin/rebase.c
>> @@ -526,6 +526,23 @@ static int rebase_write_basic_state(struct rebase_options *opts)
>> return 0;
>> }
>>
>> +static int cleanup_autostash(struct rebase_options *opts)
>> +{
>> + int ret;
>> + struct strbuf dir = STRBUF_INIT;
>> + const char *path = state_dir_path("autostash", opts);
>> +
>> + if (!file_exists(path))
>> + return 0;
>> + ret = apply_autostash(path);
>> + strbuf_addstr(&dir, opts->state_dir);
>> + if (remove_dir_recursively(&dir, 0))
>> + ret = error_errno(_("could not remove '%s'"), opts->state_dir);
>
> This seems somewhat dangerous to me though. Should we really delete the
> autostash directory in case applying the autostash has failed?Applying the stash should not fail because the rebase has not started and so HEAD, the index and the worktree are unchanged since the stash was created. If it does fail for some reason then apply_autostash() creates a new entry under refs/stash. We definitely do want to remove the directory otherwise we're left with the inconsistent state we're tying to fix.
Show 20 quoted lines
>> @@ -1851,9 +1871,14 @@ run_rebase: >> >> cleanup: >> strbuf_release(&buf); >> + strbuf_release(&msg); >> strbuf_release(&revisions); >> rebase_options_release(&options); >> free(squash_onto_name); >> free(keep_base_onto_name); >> return !!ret; >> + >> +cleanup_autostash: >> + ret |= !!cleanup_autostash(&options); >> + goto cleanup; >> } > > It's somewhat curious of a code flow to jump backwards. It might be > easier to reason about the flow if we kept track of a variable > `autostash_needs_cleanup` that we set such that all jumps can go to the > `cleanup` label instead.
It is slightly odd, but in the end I decided it was simpler to say "goto cleanup_autostash" than try and keep track of what needs cleaning up when saying "goto cleanup". There are a couple of similar examples in builtin/stash.c:show_stash() and config.c:git_config_set_multivar_in_file_gently()
Thanks for the review
Phillip
> Patrick >