On Thu, Nov 29 2018, Johannes Schindelin wrote:
> Hi Ævar,
>
> On Wed, 28 Nov 2018, Ævar Arnfjörð Bjarmason wrote:
>
>> Change the semantics of the "--range-diff" option so that the regular
>> diff options can be provided separately for the range-diff and the
>> patch. This allows for supplying e.g. --range-diff-U0 and -U1 to
>> "format-patch" to provide different context for the range-diff and the
>> patch. This wasn't possible before.
>
> I really, really dislike the `--range-diff-<random-thing>`. We have
> precedent for passing optional arguments that are passed to some other
> command, so a much more logical and consistent convention would be to use
> `--range-diff[=<diff-option>..]`, allowing all of the diff options that
> you might want to pass to the outer diff in one go rather than having a
> lengthy string of `--range-diff-this` and `--range-diff-that` options.
Where do we pass those sorts of arguments?
Reasons I did it this way:
a) Passing it as one option will require the user to double-quote those
options that take quoted arguments (e.g. --word-diff-regex), which I
thought sucked more than the prefix. On the implementation side we
couldn't leave the parsing of the command-line to the shell anymore.
b) I think people will want to tweak this very rarely, much more rarely
than e.g. -U10 in format-patch itself, so having something long-ish
doesn't sound bad.
> I only had time to skim the patch, and I have to wonder why you pass
> around full-blown `rev_info` structs for range diff (and with that really
> awful name `rd_rev`) rather than just the `diff_options` that you
> *actually* care about?
Because setup_revisions() which does all the command-line parsing needs
a rev_info, so even if we only need the diffopt in the end we need to
initiate the whole thing.
Suggestions for a better varibale name most welcome.
> Ciao,
> Dscho
>
>>
>> Ever since the "--range-diff" option was added in
>> 31e2617a5f ("format-patch: add --range-diff option to embed diff in
>> cover letter", 2018-07-22) the "rev->diffopt" we pass down to the diff
>> machinery has been the one we get from "format-patch"'s own
>> setup_revisions().
>>
>> This sort of thing is unique among the log-like commands in
>> builtin/log.c, no command than format-patch will embed the output of
>> another log-like command. Since the "rev->diffopt" is reused we need
>> to munge it before we pass it to show_range_diff(). See
>> 43dafc4172 ("format-patch: don't include --stat with --range-diff
>> output", 2018-11-22) for a related regression fix which is being
>> mostly reverted here.
>>
>> Implementation notes: 1) We're not bothering with the full teardown
>> around die() and will leak memory, but it's too much boilerplate to do
>> all the frees with/without the die() and not worth it. 2) We call
>> repo_init_revisions() for "rd_rev" even though we could get away with
>> a shallow copy like the code we're replacing (and which
>> show_range_diff() itself does). This is to make this code more easily
>> understood.
>>
>> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
>> ---
>> Documentation/git-format-patch.txt | 10 ++++++-
>> builtin/log.c | 42 +++++++++++++++++++++++-------
>> t/t3206-range-diff.sh | 41 +++++++++++++++++++++++++++++
>> 3 files changed, 82 insertions(+), 11 deletions(-)
>>
>> diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
>> index aba4c5febe..6c048f415f 100644
>> --- a/Documentation/git-format-patch.txt
>> +++ b/Documentation/git-format-patch.txt
>> @@ -24,7 +24,8 @@ SYNOPSIS
>> [--to=<email>] [--cc=<email>]
>> [--[no-]cover-letter] [--quiet] [--notes[=<ref>]]
>> [--interdiff=<previous>]
>> - [--range-diff=<previous> [--creation-factor=<percent>]]
>> + [--range-diff=<previous> [--creation-factor=<percent>]
>> + [--range-diff<common diff option>]]
>> [--progress]
>> [<common diff options>]
>> [ <since> | <revision range> ]
>> @@ -257,6 +258,13 @@ feeding the result to `git send-email`.
>> creation/deletion cost fudge factor. See linkgit:git-range-diff[1])
>> for details.
>>
>> +--range-diff<common diff option>::
>> + Other options prefixed with `--range-diff` are stripped of
>> + that prefix and passed as-is to the diff machinery used to
>> + generate the range-diff, e.g. `--range-diff-U0` and
>> + `--range-diff--no-color`. This allows for adjusting the format
>> + of the range-diff independently from the patch itself.
>> +
>> --notes[=<ref>]::
>> Append the notes (see linkgit:git-notes[1]) for the commit
>> after the three-dash line.
>> diff --git a/builtin/log.c b/builtin/log.c
>> index 02d88fa233..7658e56ecc 100644
>> --- a/builtin/log.c
>> +++ b/builtin/log.c
>> @@ -1023,7 +1023,8 @@ static void show_diffstat(struct rev_info *rev,
>> fprintf(rev->diffopt.file, "\n");
>> }
>>
>> -static void make_cover_letter(struct rev_info *rev, int use_stdout,
>> +static void make_cover_letter(struct rev_info *rev, struct rev_info *rd_rev,
>> + int use_stdout,
>> struct commit *origin,
>> int nr, struct commit **list,
>> const char *branch_name,
>> @@ -1095,13 +1096,9 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
>> }
>>
>> if (rev->rdiff1) {
>> - struct diff_options opts;
>> - memcpy(&opts, &rev->diffopt, sizeof(opts));
>> - opts.output_format &= ~(DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY);
>> -
>> fprintf_ln(rev->diffopt.file, "%s", rev->rdiff_title);
>> show_range_diff(rev->rdiff1, rev->rdiff2,
>> - rev->creation_factor, 1, &opts);
>> + rev->creation_factor, 1, &rd_rev->diffopt);
>> }
>> }
>>
>> @@ -1485,6 +1482,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
>> struct commit *commit;
>> struct commit **list = NULL;
>> struct rev_info rev;
>> + struct rev_info rd_rev;
>> struct setup_revision_opt s_r_opt;
>> int nr = 0, total, i;
>> int use_stdout = 0;
>> @@ -1603,6 +1601,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
>> init_log_defaults();
>> git_config(git_format_config, NULL);
>> repo_init_revisions(the_repository, &rev, prefix);
>> + repo_init_revisions(the_repository, &rd_rev, prefix);
>> rev.commit_format = CMIT_FMT_EMAIL;
>> rev.expand_tabs_in_log_default = 0;
>> rev.verbose_header = 1;
>> @@ -1689,8 +1688,32 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
>> rev.preserve_subject = keep_subject;
>>
>> argc = setup_revisions(argc, argv, &rev, &s_r_opt);
>> - if (argc > 1)
>> - die(_("unrecognized argument: %s"), argv[1]);
>> + if (argc > 1) {
>> + struct argv_array args = ARGV_ARRAY_INIT;
>> + const char *prefix = "--range-diff";
>> + int have_prefix = 0;
>> +
>> + for (i = 0; i < argc; i++) {
>> + struct strbuf sb = STRBUF_INIT;
>> + char *str;
>> +
>> + strbuf_addstr(&sb, argv[i]);
>> + if (starts_with(argv[i], prefix)) {
>> + have_prefix = 1;
>> + strbuf_remove(&sb, 0, strlen(prefix));
>> + }
>> + str = strbuf_detach(&sb, NULL);
>> + strbuf_release(&sb);
>> +
>> + argv_array_push(&args, str);
>> + }
>> +
>> + if (!have_prefix)
>> + die(_("unrecognized argument: %s"), argv[1]);
>> + argc = setup_revisions(args.argc, args.argv, &rd_rev, NULL);
>> + if (argc > 1)
>> + die(_("unrecognized argument: %s"), argv[1]);
>> + }
>>
>> if (rev.diffopt.output_format & DIFF_FORMAT_NAME)
>> die(_("--name-only does not make sense"));
>> @@ -1702,7 +1725,6 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
>> if (!use_patch_format &&
>> (!rev.diffopt.output_format ||
>> rev.diffopt.output_format == DIFF_FORMAT_PATCH))
>> - /* Needs to be mirrored in show_range_diff() invocation */
>> rev.diffopt.output_format = DIFF_FORMAT_DIFFSTAT | DIFF_FORMAT_SUMMARY;
>> if (!rev.diffopt.stat_width)
>> rev.diffopt.stat_width = MAIL_DEFAULT_WRAP;
>> @@ -1877,7 +1899,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
>> if (cover_letter) {
>> if (thread)
>> gen_message_id(&rev, "cover");
>> - make_cover_letter(&rev, use_stdout,
>> + make_cover_letter(&rev, &rd_rev, use_stdout,
>> origin, nr, list, branch_name, quiet);
>> print_bases(&bases, rev.diffopt.file);
>> print_signature(rev.diffopt.file);
>> diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh
>> index bc5facc1cd..6916103888 100755
>> --- a/t/t3206-range-diff.sh
>> +++ b/t/t3206-range-diff.sh
>> @@ -308,6 +308,35 @@ test_expect_success 'format-patch with <common diff option>' '
>> --range-diff=topic~..topic changed~..changed >actual.raw &&
>> sed -ne "/^1:/,/^--/p" <actual.raw >actual.range-diff &&
>> sed -e "s|:$||" >expect <<-\EOF &&
>> + 1: a63e992 ! 1: d966c5c s/12/B/
>> + @@ -8,7 +8,7 @@
>> + @@
>> + 9
>> + 10
>> + - B
>> + + BB
>> + -12
>> + +B
>> + 13
>> + -- :
>> + EOF
>> + test_cmp expect actual.range-diff &&
>> + sed -ne "/^--- /,/^--/p" <actual.raw >actual.diff &&
>> + sed -e "s|:$||" >expect <<-\EOF &&
>> + --- a/file
>> + +++ b/file
>> + @@ -12 +12 @@ BB
>> + -12
>> + +B
>> + -- :
>> + EOF
>> + test_cmp expect actual.diff &&
>> +
>> + # -U0 & --range-diff-U0
>> + git format-patch --cover-letter --stdout -U0 --range-diff-U0 \
>> + --range-diff=topic~..topic changed~..changed >actual.raw &&
>> + sed -ne "/^1:/,/^--/p" <actual.raw >actual.range-diff &&
>> + sed -e "s|:$||" >expect <<-\EOF &&
>> 1: a63e992 ! 1: d966c5c s/12/B/
>> @@ -11 +11 @@
>> - B
>> @@ -327,4 +356,16 @@ test_expect_success 'format-patch with <common diff option>' '
>> test_cmp expect actual.diff
>> '
>>
>> +test_expect_success 'format-patch option parsing with --range-diff-*' '
>> + test_must_fail git format-patch --stdout --unknown \
>> + master..unmodified 2>stderr &&
>> + test_i18ngrep "unrecognized argument: --unknown" stderr &&
>> + test_must_fail git format-patch --stdout --range-diff-unknown \
>> + master..unmodified 2>stderr &&
>> + test_i18ngrep "unrecognized argument: --range-diff-unknown" stderr &&
>> + test_must_fail git format-patch --stdout --unknown --range-diff-unknown \
>> + master..unmodified 2>stderr &&
>> + test_i18ngrep "unrecognized argument: --unknown" stderr
>> +'
>> +
>> test_done
>> --
>> 2.20.0.rc1.387.gf8505762e3
>>
>>
