Re: [PATCH 4/5] rebase -i: don't fork git checkout
- From
- Phillip Wood <phillip.wood123@gmail.com>
- Date
- Sep 9, 2021, 13:57 UTC
- Message-ID
- <408dc1d3-44b8-a955-4d7b-94f23fa8a6bc@gmail.com>
- In-Reply-To
- <e7224105-83c6-7f12-f63a-474bd477583a@gmail.com>
Hi Philippe
On 09/09/2021 13:40, Philippe Blain wrote:
Show 17 quoted lines
>>> While in general I think it's a good thing to avoid forking, this >>> change might result in behavioral differences. Any config that >>> affects 'git checkout' but not the internal 'reset.c::reset_head' >>> function might play a role in the rebase UX. >>> >>> One that immediately came to mind is 'submodule.recurse'. This >>> initial 'onto' checkout was pretty much the only part of 'git >>> rebase' that did something useful for submodules, so it's kind of >>> sad to see it regress. >> >> Thanks for pointing that out. As a non-submodule user my question >> would be is it actually useful for the initial checkout to work that >> way if the rest of rebase (and the checkout for the am backend) >> ignores submodules? reset.c::reset_head() just uses unpack trees like >> checkout so if rebase read 'submodule.recurse' then reset_head() >> would work like 'git checkout' and also 'git rebase --abort' and the >> "reset" command in the todo list would start checking out submodules.
it would also affect fast-forwards
Show 38 quoted lines
>> I'm reluctant to do that until the merge backend also handles >> submodules unless there is a good reason that such partial submodule >> support would help submodule users. > > Yeah, it's not that useful, I have to admit; it can also be very confusing > since some parts of rebase are affected, and some not. For example, any > time > the rebase stops, like for 'edit', 'break', and when there are > conflicts, the > submodules are not updated. So I think a full solution is better than a > partial > solution; in the meantime I'm thinking the change you are proposing > would actually > be less confusing, even if it slightly changes behaviour... > > As an aside, I *think* reading submodule.recurse in rebase like it's > done in checkout > et al., i.e. something like this: > > diff --git a/builtin/rebase.c b/builtin/rebase.c > index 33e0961900..125ec907e4 100644 > --- a/builtin/rebase.c > +++ b/builtin/rebase.c > @@ -26,6 +26,7 @@ > #include "rerere.h" > #include "branch.h" > #include "sequencer.h" > +#include "submodule.h" > #include "rebase-interactive.h" > #include "reset.h" > > @@ -1106,6 +1107,9 @@ static int rebase_config(const char *var, const > char *value, void *data) > return git_config_string(&opts->default_backend, var, value); > } > > + if (!strcmp(var, "submodule.recurse")) > + return git_default_submodule_config(var, value, data);
That looks about right to me though I think it would be safer to call git_default_submodule_config() for submodule.* rather than just submodule.recurse
Show 8 quoted lines
> return git_default_config(var, value, data); > } > > > would actually also affect the merges > performed during the rebase, since that would affect the "global" state > in submodule.c. > I hacked exactly that the other day but did not test extensively...
merge-ort.c:checkout() which is used by merge_switch_to_result() uses unpack_trees() so it will pick up the global state and hopefully should just work (cc'ing Elijah to check as I didn't look what happens when there are conflicts). merge-recursive.c:update_file_flags() does this when updating the work tree
if (S_ISGITLINK(contents->mode)) { /*
* We may later decide to recursively descend into
* the submodule directory and update its index
* and/or work tree, but we do not do that now.
*/
update_wd = 0;
goto update_index;
}
so it looks like it does not update the submodule directory. Given merge-ort is now the default perhaps it's time for rebase (and cherry-pick/revert) to start reading the submodule config settings (we parse the config before we know if we'll be using merge-ort so I don't know how easy it would be to only parse the submodule settings if we are using merge-ort).
Best Wishes
Phillip