Re: [PATCH 1/1] Let rebase.reschedulefailedexec only affect interactive rebases

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Junio,

On Thu, 27 Jun 2019, Junio C Hamano wrote:

> "Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com>
> writes:
>
> > From: Johannes Schindelin <johannes.schindelin@gmx.de>
> >
> > It does not make sense to stop non-interactive rebases when that config
> > setting is set to `true`.
>
> The reader is assumed to know that that config setting is only about
> interactive rebases, including "rebase -x", which probably is an OK
> explanation.

You're right, it is okay, but could be better.

> The subject needs a bit more work, though.
>
> "rebase: ignore rebase.reschedulefailedexec unless interative"
>
> or something like that, perhaps.

Right.

> > @@ -929,7 +930,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
> >  		OPT_BOOL(0, "root", &options.root,
> >  			 N_("rebase all reachable commits up to the root(s)")),
> >  		OPT_BOOL(0, "reschedule-failed-exec",
> > -			 &options.reschedule_failed_exec,
> > +			 &reschedule_failed_exec,
> >  			 N_("automatically re-schedule any `exec` that fails")),
> >  		OPT_END(),
> >  	};
> > @@ -1227,8 +1228,10 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
> >  		break;
> >  	}
> >
> > -	if (options.reschedule_failed_exec && !is_interactive(&options))
> > +	if (reschedule_failed_exec > 0 && !is_interactive(&options))
>
> OK, it used to be that we got affected by what came from "options",
> which was read from the configuration.  Now we only pay attention to
> the command line, which makes sense.
>
> At this point, we have already examined '-x' and called
> imply_interative(), so this should trigger for '-x' (without '-i'),
> right?

Yes, at this point we have done all the parsing and automatic implying,
and check for incompatible options.

> >  		die(_("--reschedule-failed-exec requires an interactive rebase"));
>
> I wonder if users understand that '-x' is "an interctive rebase".
> The documentation can read both ways, and one of these may want to
> be clarified.
>
> 	-x <cmd>, --exec <cmd>
> 	...
> 	This uses the --interactive machinery internally, but it can
> 	be run without an explicit --interactive.
>
> Is it saying that use of interactive machinery is an impelementation
> detail the users should not concern themselves (in which case, the
> message given to "die()" above is misleading---not a new problem
> with this patch, though)?  Is it saying "-x" makes it plenty clear
> that the user wants interactive behaviour, so the users do not need
> to spell out --interactive in order to ask for it (in which case,
> "die()" message is fine, but "... internally, but ..." is
> misleading)?

Hmm. What would you think about:

  		die(_("--reschedule-failed-exec requires --exec or --interactive"));

?

It is still not _complete_, but at least it should be a ton less
confusing.

> > +	if (reschedule_failed_exec >= 0)
> > +		options.reschedule_failed_exec = reschedule_failed_exec;
>
> OK, here we recover the bit that is only stored in a local variable
> and pass it into cmd_rebase__interactive() machinery via the options
> structure, which lets the codepath after this point oblivious to
> this change, which is good ;-).
>
> >  	if (options.git_am_opts.argc) {
> >  		/* all am options except -q are compatible only with --am */
> > diff --git a/t/t3418-rebase-continue.sh b/t/t3418-rebase-continue.sh
> > index bdaa511bb0..4eff14dae5 100755
> > --- a/t/t3418-rebase-continue.sh
> > +++ b/t/t3418-rebase-continue.sh
> > @@ -265,4 +265,12 @@ test_expect_success '--reschedule-failed-exec' '
> >  	test_i18ngrep "has been rescheduled" err
> >  '
> >
> > +test_expect_success 'rebase.reschedulefailedexec only affects `rebase -i`' '
> > +	test_config rebase.reschedulefailedexec true &&
> > +	test_must_fail git rebase -x false HEAD^ &&
>
> These three lines gives us a concise summary of this patch ;-)
>
>  - The test title can serve as a starting point for a much better
>    patch title.
>
>  - We trigger for '-x' without requiring '-i'.

I changed the oneline to

	rebase --am: ignore rebase.reschedulefailedexec

This gives credit to the implementation details, as appropriate for commit
messages, and the error message still tries to be as helpful as possible
for users (who do not necessarily need to know that there are two
backends).

At this point, I am _really_ glad that we only have two backends left (for
all practical purposes, I don't count --preserve-merges).

Ciao,
Dscho

> > +	grep "^exec false" .git/rebase-merge/git-rebase-todo &&
> > +	git rebase --abort &&
> > +	git rebase HEAD^
> > +'
> > +
> >  test_done
>