Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> 于2021年3月16日周二 下午8:52写道：
> > + if (run_command(&run_trailer))
> > + strvec_clear(&run_trailer.args);
>
> This is git-commit, shouldn't we die() here instead of ignoring errors
> in sub-processes?
After thinking about it carefully, your opinion is more
reasonable, because if the user uses the wrong `--trailer`
and does not get the information he needs, I think he will
have to use `--amend` to modify, and `die()` can exit
this commit directly.
>
> > + strvec_clear(&trailer_args);
> > + }
> > +
> > /*
> > * Reject an attempt to record a non-merge empty commit without
> > * explicit --allow-empty. In the cherry-pick case, it may be
> > @@ -1507,6 +1529,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
> > OPT_STRING(0, "fixup", &fixup_message, N_("commit"), N_("use autosquash formatted message to fixup specified commit")),
> > OPT_STRING(0, "squash", &squash_message, N_("commit"), N_("use autosquash formatted message to squash specified commit")),
> > OPT_BOOL(0, "reset-author", &renew_authorship, N_("the commit is authored by me now (used with -C/-c/--amend)")),
> > + OPT_CALLBACK_F(0, "trailer", NULL, N_("trailer"), N_("trailer(s) to add"), PARSE_OPT_NONEG, opt_pass_trailer),
> > OPT_BOOL('s', "signoff", &signoff, N_("add a Signed-off-by trailer")),
>
> Not required for this change, but perhaps a change here to N_() (if we
> can get it to fit) + doc update saying that we prefer
> --trailer="Signed-Off-By: to --signoff"? More on that later.
>
> > OPT_FILENAME('t', "template", &template_file, N_("use specified template file")),
> > OPT_BOOL('e', "edit", &edit_flag, N_("force edit of commit")),
> > diff --git a/t/t7502-commit-porcelain.sh b/t/t7502-commit-porcelain.sh
> > index 6396897cc818..0acf23799931 100755
> > --- a/t/t7502-commit-porcelain.sh
> > +++ b/t/t7502-commit-porcelain.sh
> > @@ -154,6 +154,26 @@ test_expect_success 'sign off' '
> >
> > '
> >
> > +test_expect_success 'trailer' '
> > + >file1 &&
> > + git add file1 &&
> > + git commit -s --trailer "Signed-off-by:C O Mitter1 <committer1@xxxxxxxxxxx>" \
> > + --trailer "Helped-by:C O Mitter2 <committer2@xxxxxxxxxxx>" \
> > + --trailer "Reported-by:C O Mitter3 <committer3@xxxxxxxxxxx>" \
> > + --trailer "Mentored-by:C O Mitter4 <committer4@xxxxxxxxxxx>" \
> > + -m "hello" &&
> > + git cat-file commit HEAD >commit.msg &&
> > + sed -e "1,7d" commit.msg >actual &&
> > + cat >expected <<-\EOF &&
> > + Signed-off-by: C O Mitter <committer@xxxxxxxxxxx>
> > + Signed-off-by: C O Mitter1 <committer1@xxxxxxxxxxx>
> > + Helped-by: C O Mitter2 <committer2@xxxxxxxxxxx>
> > + Reported-by: C O Mitter3 <committer3@xxxxxxxxxxx>
> > + Mentored-by: C O Mitter4 <committer4@xxxxxxxxxxx>
> > + EOF
> > + test_cmp expected actual
> > +'
> > +
>
> How does this interact with cases where the user has configured
> "trailer.separators" to have a value that doesn't contain ":"? I
> haven't tested, but my reading of git-interpret-trailers(1) is that if
> you supplied "=" instead that case would just work:
>
> By default only : is recognized as a trailer separator, except that
> = is always accepted on the command line for compatibility with
> other git commands.
>
But interpret_trailers interface allow us use "=" instead of other separators.
I did a simple test and modified the configuration "trailer.separators"
and it still works. Now things are good here:
$ git -c trailer.separators="@" commit --trailer="Signed-off-by=C O <email>"
or
$ git -c trailer.separators="@" commit --trailer="Signed-off-by@C O <email>"
Both can work normally,
--trailer="Signed-off-by@ C O <email>"
will output in the commit message.
> I don't know if that does the right thing in the presence of
> --if-exists=add.
>
Yesterday, Christian Couder and I had already discussed this issue:
Your idea is correct, I should not add "--if-exists = add", this will destroy
the user's rights to configure by using `git -c trailer.if-exist`.
> So it would be good to update these tests so you test:
>
> * For the --if-exists=add case at all, there's no tests for it
> now. I.e. add some trailers manually to the commit (via -F or
> whatever) and then see if they get added to, replacet etc.
>
> * Ditto but for the user having configured trailer.separators (see the
> test_config helper for how to set config in a test). I.e. if it's "="
> does adding trailers work, how about if it's "=" on the CLI but the
> config/commit message has ";" instead of ":" or something?
>
As mentioned above, it works normally.
> * Hrm, actually I think tweaking "-c trailer.ifexists" won't work at
> all, since the CLI switch would override it. I honestly don't know,
> but why not not supply it and keep the addIfDifferentNeighbor
> default?
>
> If it's essential that seems like a good test / documentation
> addition...
>
> * For the above -c ... case I can't think of a good way to deal with it
> that doesn't involve pulling in git_trailer_config() into
> git_commit_config(), but perhaps the least nasty way is to just set a
> flag in git_commit_config() if we see a "trailer.ifexists" flag, and
> if so don't provide "--if-exists=add", if there's no config (this
> will include "git -c ... commit" we set provide "--if-exists=add" )
> or as noted above, maybe we can skip the whole thing and use the
> addIfDifferentNeighbor default.
>
Has been restored to the default settings.
> And, not needed for this patch but worth thinking about:
>
> * We pass through --trailer to git-interpret-trailers, what should we
> do about the other options? Should git-commit eventually support
> --trailer-where and pass it along as --where to
> git-interpret-trailers, or is "git -c trailer.where=... commit" good
> enough?
>
Logically speaking, `interpret_trailers` should be dedicated to `commit`
or other sub-commands that require trailers.
But I think that in the later stage, the parse_options of the `cmd_commit`
can keep the unrecognized options, and then these choices can be directly
passed to the `interpret_trailers` backend.
> * It would be good to test for and document if that "-c trailer.*"
> trick works (no reason it shouldn't). I.e. to add something like this
> after what you have (along with tests, and check if it's even true):
>
I haven't tested them for the time being, but I will do it.
> Only the `--trailer` argument to
> linkgit:git-interpret-trailers[1] is supported. Other
> pass-through switches may be added in the future, but currently
> you'll need to pass arguments to
> linkgit:git-interpret-trailers[1] along as config, e.g. `git -c
> trailer.where=start commit [...] --trailer=[...]`.
>
I think this is worth writing in the documentation.
> * We have a longer-term goal of having the .mailmap apply to trailers,
> it would be nice if git-interpret-trailers had some fuzzy-matching to
> check if the RHS of a trailer is a name/E-Mail pair, and if so did
> stricter validation on it with the ident functions we use for fsck
> etc. (that's copied & subtly different in several different places in
> the codebase, unfortunately[1]).
>
I may not know much about fuzzy-matching, which may be worth studying later.
> More thoughts:
>
> * Having written all the above I checked how --signoff is implemented.
>
> It seems to me to be a good idea to (at least for testing) convert
> the --signoff trailer to your implementation. We have plenty of tests
> for it, does migrating it over pass or fail those?
>
I don’t know how to migrating yet, it may take a long time.
Even I think I can leave it as #leftoverbit later.
> * I also agree with Junio that we shouldn't have a --fixed-by or
> whatever and wouldn't add --signoff today, but it seems very useful
> to me to have a shortcut like:
>
> --trailer "Signed-off-by"
>
> I.e. omitting the value, or:
>
> --trailer "Signed-off-by="
>
> Or some other thing we deem sufficiently useful/sane
> syntax/unambiguous.n
>
> Then the value would be provided by fmt_name(WANT_COMMITTER_IDENT)
> just as we do in append_signoff() now. I think a *very common* case
> for this would be something like:
>
> git commit --amend -v --trailer "Reviewed-by"
>
> And it would be useful to help that along and not have to do:
>
> git commit --amend -v --trailer "Reviewed-by=$(git config user.name) <$(git config user.email)>"
>
> Or worse yet, manually typo your name/e-mail address, as I'm sure I
> and many others will inevitably do when using this option...
>
I think this idea is very good and easy to implement.
We only need to do a simple string match when we get the "trailer" string,
If it can be completed, it can indeed bring great convenience to users.
> 1. https://lore.kernel.org/git/87bld8ov9q.fsf@xxxxxxxxxxxxxxxxxxx/
Thanks, Ævar Arnfjörð Bjarmason!
--
ZheNing Hu
