Re: [BUG?] 'git rebase --update-refs --whitespace=fix' incompatible, but not enforced

>> +       /* Check for arguments that imply --apply before checking --apply itself. */
>> +       if (options.update_refs) {
>> +               const char *incompatible = NULL;
>> +               if (options.git_am_opts.nr)
>> +                       incompatible = options.git_am_opts.v[0];
>> +               else if (options.type == REBASE_APPLY)
>> +                       incompatible = "--apply";
> 
> git_am_opts can include "-q" which is not incompatible since it's also
> supported under the merge backend.

>> +
>> +               if (incompatible) {
>> +                       int from_config = 0;
>> +                       if (!git_config_get_bool("rebase.updaterefs", &from_config) &&
>> +                           from_config) {
>> +                               warning(_("you have 'rebase.updateRefs' enabled in your config, "
>> +                                         "but it is incompatible with one or more options;"));
>> +                               warning(_("run again with '--no-update-refs' to resolve the issue"));
>> +                       }
>> +                       die(_("options '%s' and '%s' cannot be used together"),
>> +                           "--upate-refs", incompatible);
>> +               }
>> +       }
> 
> We already have imply_merge() to catch the range of incompatibilities;
> can we just use it?

>> +
>>         if (trace2_is_enabled()) {
>>                 if (is_merge(&options))
>>                         trace2_cmd_mode("interactive");
>> diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
>> index 462cefd25df..8681c8a07f8 100755
>> --- a/t/t3404-rebase-interactive.sh
>> +++ b/t/t3404-rebase-interactive.sh
>> @@ -2123,6 +2123,18 @@ test_expect_success '--update-refs: check failed ref update' '
>>         test_cmp expect err.trimmed
>>  '
>>
>> +test_expect_success '--apply options are incompatible with --update-refs' '
>> +       for opt in "--whitespace=fix" "-C1" "--apply"
>> +       do
>> +               test_must_fail git rebase "$opt" --update-refs HEAD~1 2>err &&
>> +               grep "options '\''--upate-refs'\'' and '\''$opt'\'' cannot be used together" err &&
>> +
>> +               test_must_fail git -c rebase.updateRefs=true rebase "$opt" HEAD~1 2>err &&
>> +               grep "options '\''--upate-refs'\'' and '\''$opt'\'' cannot be used together" err &&
>> +               grep "you have '\''rebase.updateRefs'\'' enabled" err || return 1
>> +       done
>> +'
>> +
> 
> t3422 exists specifically for checking for incompatibilities of such
> options; the test should go over there.
> 
> I have both changes over at
> https://github.com/gitgitgadget/git/pull/1466; it doesn't include the
> "--no-update-refs" hint, but maybe that's good enough?  If so, I can
> submit it.  If not, do you want to alter or adopt some parts of my
> patch and submit a v2?