format-patch: add --range-diff option to embed diff in cover letter
When submitting a revised version of a patch series, it can be helpful
(to reviewers) to include a summary of changes since the previous
attempt in the form of a range-diff, however, doing so involves manually
copy/pasting the diff into the cover letter.
Add a --range-diff option to automate this process. The argument to
--range-diff specifies the tip of the previous attempt against which to
generate the range-diff. For example:
git format-patch --cover-letter --range-diff=v1 -3 v2
(At this stage, the previous attempt and the patch series being
formatted must share a common base, however, a subsequent enhancement
will make it possible to specify an explicit revision range for the
previous attempt.)
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
index f8a0617..e7f404b 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt
@@ -24,6 +24,7 @@
[--to=<email>] [--cc=<email>]
[--[no-]cover-letter] [--quiet] [--notes[=<ref>]]
[--interdiff=<previous>]
+ [--range-diff=<previous>]
[--progress]
[<common diff options>]
[ <since> | <revision range> ]
@@ -238,6 +239,15 @@
the series being formatted (for example `git format-patch
--cover-letter --interdiff=feature/v1 -3 feature/v2`).
+--range-diff=<previous>::
+ As a reviewer aid, insert a range-diff (see linkgit:git-range-diff[1])
+ into the cover letter showing the differences between the previous
+ version of the patch series and the series currently being formatted.
+ `previous` is a single revision naming the tip of the previous
+ series which shares a common base with the series being formatted (for
+ example `git format-patch --cover-letter --range-diff=feature/v1 -3
+ feature/v2`).
+
--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 fcc2f4d..4b65673 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -32,6 +32,7 @@
#include "commit-slab.h"
#include "repository.h"
#include "interdiff.h"
+#include "range-diff.h"
#define MAIL_DEFAULT_WRAP 72
@@ -1089,6 +1090,12 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
fprintf_ln(rev->diffopt.file, "%s", rev->idiff_title);
show_interdiff(rev, 0);
}
+
+ if (rev->rdiff1) {
+ fprintf_ln(rev->diffopt.file, "%s", _("Range-diff:"));
+ show_range_diff(rev->rdiff1, rev->rdiff2,
+ rev->creation_factor, 1, &rev->diffopt);
+ }
}
static const char *clean_message_id(const char *msg_id)
@@ -1438,6 +1445,17 @@ static const char *diff_title(struct strbuf *sb, int reroll_count,
return sb->buf;
}
+static void infer_range_diff_ranges(struct strbuf *r1,
+ struct strbuf *r2,
+ const char *prev,
+ struct commit *head)
+{
+ const char *head_oid = oid_to_hex(&head->object.oid);
+
+ strbuf_addf(r1, "%s..%s", head_oid, prev);
+ strbuf_addf(r2, "%s..%s", prev, head_oid);
+}
+
int cmd_format_patch(int argc, const char **argv, const char *prefix)
{
struct commit *commit;
@@ -1467,6 +1485,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
struct progress *progress = NULL;
struct oid_array idiff_prev = OID_ARRAY_INIT;
struct strbuf idiff_title = STRBUF_INIT;
+ const char *rdiff_prev = NULL;
+ struct strbuf rdiff1 = STRBUF_INIT;
+ struct strbuf rdiff2 = STRBUF_INIT;
const struct option builtin_format_patch_options[] = {
{ OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
@@ -1543,6 +1564,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
OPT_CALLBACK(0, "interdiff", &idiff_prev, N_("rev"),
N_("show changes against <rev> in cover letter or single patch"),
parse_opt_object_name),
+ OPT_STRING(0, "range-diff", &rdiff_prev, N_("refspec"),
+ N_("show changes against <refspec> in cover letter")),
OPT_END()
};
@@ -1775,6 +1798,16 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
_("Interdiff against v%d:"));
}
+ if (rdiff_prev) {
+ if (!cover_letter)
+ die(_("--range-diff requires --cover-letter"));
+
+ infer_range_diff_ranges(&rdiff1, &rdiff2, rdiff_prev, list[0]);
+ rev.rdiff1 = rdiff1.buf;
+ rev.rdiff2 = rdiff2.buf;
+ rev.creation_factor = RANGE_DIFF_CREATION_FACTOR_DEFAULT;
+ }
+
if (!signature) {
; /* --no-signature inhibits all signatures */
} else if (signature && signature != git_version_string) {
@@ -1898,6 +1931,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
done:
oid_array_clear(&idiff_prev);
strbuf_release(&idiff_title);
+ strbuf_release(&rdiff1);
+ strbuf_release(&rdiff2);
return 0;
}
diff --git a/revision.h b/revision.h
index b30ea3a..01fd7e2 100644
--- a/revision.h
+++ b/revision.h
@@ -218,6 +218,11 @@ struct rev_info {
const struct object_id *idiff_oid2;
const char *idiff_title;
+ /* range-diff */
+ const char *rdiff1;
+ const char *rdiff2;
+ int creation_factor;
+
/* commit counts */
int count_left;
int count_right;
diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh
index 2237c7f..dd854b6 100755
--- a/t/t3206-range-diff.sh
+++ b/t/t3206-range-diff.sh
@@ -142,4 +142,16 @@
test_cmp expected actual
'
+for prev in topic
+do
+ test_expect_success "format-patch --range-diff=$prev" '
+ git format-patch --stdout --cover-letter --range-diff=$prev \
+ master..unmodified >actual &&
+ grep "= 1: .* s/5/A" actual &&
+ grep "= 2: .* s/4/A" actual &&
+ grep "= 3: .* s/11/B" actual &&
+ grep "= 4: .* s/12/B" actual
+ '
+done
+
test_done
