Re: [PATCH 3/3] Inform about fast-forwarding of submodules during merge

Stefan Beller [off-list ref] writes:

From: Leif Middelschulte <redacted>

Subject: merge-recursive: give notice when submodule commit gets fast-forwarded

perhaps?

 	/* Case #1: a is contained in b or vice versa */
 	if (in_merge_bases(commit_a, commit_b)) {
 		oidcpy(result, b);
+		if (show(o, 3)) {
+			output(o, 1, _("Fast-forwarding submodule %s to the following commit:"), path);
+			output_commit_title(o, commit_b);
+		} else if (show(o, 2))
+			output(o, 2, _("Fast-forwarding submodule %s to %s"), path, oid_to_hex(b));
+		else
+			; /* no output */
+

merge.verbosity::
	Controls the amount of output shown by the recursive merge
	strategy.  Level 0 outputs nothing except a final error
	message if conflicts were detected. Level 1 outputs only
	conflicts, 2 outputs conflicts and file changes.  Level 5 and
	above outputs debugging information.  The default is level 2.
	Can be overridden by the `GIT_MERGE_VERBOSITY` environment variable.

So, by default, we report the fact that we update submodule to a
particular commit, which is quite similar to how we report auto
merged paths using the content level 3-way merge; when you squint
your eyes, the "fast-forward" of submodules look somewhat like a
content-level 3-way merge anyway ;-)

And at level 3, which currently is used to report a non-event that
does not change the result of the merge from what was naturally
expected, we give a bit more detail by citing the commit the
submodule gets fast-forwarded to [*1*].

Sort of makes sense.


[Footnote]

*1* I wonder if that is really necessary, though---we do not give
"here is a diff" or "this is the new contents" after a path gets
merged for normal files.  And if it is needed perhaps because
submodules are so special, I wonder if we also need to give the
commit the submodule gets fast-forwarded from, i.e. the original
one, the same way.