Re: Problems with ra/rebase-i-more-options - should we revert it?

Hi Phillip,

On Sun, 12 Jan 2020, Phillip Wood wrote:

On 12/01/2020 16:12, Phillip Wood wrote:

quoted

I'm concerned that there are some bugs in this series and think
it may be best to revert it before releasing 2.25.0. Jonathan
Nieder posted a bug report on Friday [1] which I think is caused
by this series. While trying to reproduce Jonathan's bug I came
up with the test below which fails, but not in the same way.

Thank you so much for your thoughts and your work on this. For what it's
worth, I totally agree with your assessment and your suggestion to revert
those patches _before_ releasing v2.25.0. (I seem to remember vaguely that
there were repeated requests for better test coverage and that those
requests went unaddressed, so I would not be surprised if there were more
unfortunate surprises waiting for us.)

Doh I forgot to add --committer-date-is-author-date to the rebase
command line in that test. It passes with that added - how
embarrassing. However it does appear that it prefixes the date in
GIT_COMMITTER_DATE with @@ rather than @. I think (though am not
completely certain yet) the reason the test still passes is that
the date has more than 8 digits so although
match_object_header_date() fails because of the '@@'
match_digit() succeeds once the loop in parse_date_basic() strips
that prefix. Jonathan's test date only has 7 digits so
match_digit() does not treat it as a number of seconds since the
start of the epoch and fails to parse it. The fix for the @@ is
quite simple, the date we read from the author script already has
an @ so we don't need to add another. The diff below shows a
basic fix but we should get rid of datebuf altogether as we don't
need it. I need a break now I'll try and put a patch together
later in the week if no one else has by then.

Thank you so much!

I have to admit that I have not analyzed the code before this hunk (it
would be much easier to increase the context in a non-static reviewing
environment, e.g. on GitHub, but the mailing list does not allow for
that), so I do not know just _how_ likely our `date` here is going to
change or remain prefixed by a `@`. Therefore, this suggestion might be
totally stupid: `"@%s", date + (*date == '@')`

Thanks again,
Dscho

                res = setenv("GIT_COMMITTER_DATE",
                             opts->ignore_date ? "" : datebuf.buf, 1);

quoted

The
test coverage of this series has always been pretty poor and I
think it needs improving for us to have confidence in it. I'm
also concerned that at least one of the
tests ('--committer-date-is-author-date works with rebase -r')
does not detect failures properly in the code below

	while read HASH
	do
		git show $HASH --pretty="format:%ai" >authortime
		git show $HASH --pretty="format:%ci" >committertime
		test_cmp authortime committertime
	done <rev_list


Best Wishes

Phillip

[1] https://lore.kernel.org/git/20200110231436.GA24315@google.com/ (local)

--- >8 ---
diff --git a/t/t3433-rebase-options-compatibility.sh b/t/t3433-rebase-options-compatibility.sh
index 5166f158dd..c81e1d7167 100755
--- a/t/t3433-rebase-options-compatibility.sh
+++ b/t/t3433-rebase-options-compatibility.sh

@@ -6,6 +6,7 @@
  test_description='tests to ensure compatibility between am and interactive backends'

  . ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-rebase.sh

  GIT_AUTHOR_DATE="1999-04-02T08:03:20+05:30"
  export GIT_AUTHOR_DATE

@@ -99,6 +100,22 @@ test_expect_success '--committer-date-is-author-date works with rebase -r' '
         done <rev_list
  '

+test_expect_success '--committer-date-is-author-date works when committing conflict resolution' '
+       git checkout commit2 &&
+       (
+               set_fake_editor &&
+               FAKE_LINES=2 &&
+               export FAKE_LINES &&
+               test_must_fail git rebase -i HEAD^^
+       ) &&
+       echo resolved > foo &&
+       git add foo &&
+       git rebase --continue &&
+       git log -1 --format=%at commit2 >expect &&
+       git log -1 --format=%ct HEAD >actual &&
+       test_cmp expect actual
+'
+
  # Checking for +0000 in author time is enough since default
  # timezone is UTC, but the timezone used while committing
  # sets to +0530.