[PATCH 02/14] format-patch: add --interdiff 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 an interdiff, however, doing so involves manually copy/pasting the diff into the cover letter.
Add an --interdiff option to automate this process. The argument to --interdiff specifies the tip of the previous attempt against which to generate the interdiff. For example:
git format-patch --cover-letter --interdiff=v1 -3 v2
The previous attempt and the patch series being formatted must share a common base.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
---
Documentation/git-format-patch.txt | 9 +++++++++
Makefile | 1 +
builtin/log.c | 24 ++++++++++++++++++++++--
interdiff.c | 17 +++++++++++++++++
interdiff.h | 8 ++++++++
revision.h | 4 ++++
t/t4014-format-patch.sh | 17 +++++++++++++++++
7 files changed, 78 insertions(+), 2 deletions(-)
create mode 100644 interdiff.c
create mode 100644 interdiff.h
Show changes to 7 files +78 −2
Documentation/git-format-patch.txt, Makefile, builtin/log.c, interdiff.c, interdiff.h, revision.h, t/t4014-format-patch.sh
diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
index b41e1329a7..a1b1bafee7 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt
@@ -23,6 +23,7 @@ SYNOPSIS
[(--reroll-count|-v) <n>]
[--to=<email>] [--cc=<email>]
[--[no-]cover-letter] [--quiet] [--notes[=<ref>]]
+ [--interdiff=<previous>]
[--progress]
[<common diff options>]
[ <since> | <revision range> ]
@@ -228,6 +229,14 @@ feeding the result to `git send-email`.
containing the branch description, shortlog and the overall diffstat. You can
fill in a description in the file before sending it out.
+--interdiff=<previous>::
+ As a reviewer aid, insert an interdiff 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 --interdiff=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/Makefile b/Makefile
index 41b93689ad..2af389c0d9 100644
--- a/Makefile
+++ b/Makefile
@@ -872,6 +872,7 @@ LIB_OBJS += linear-assignment.o
LIB_OBJS += help.o
LIB_OBJS += hex.o
LIB_OBJS += ident.o
+LIB_OBJS += interdiff.o
LIB_OBJS += kwset.o
LIB_OBJS += levenshtein.o
LIB_OBJS += line-log.o
diff --git a/builtin/log.c b/builtin/log.c
index 873aabcf40..1020b78477 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -30,6 +30,7 @@
#include "gpg-interface.h"
#include "progress.h"
#include "commit-slab.h"
+#include "interdiff.h"
#define MAIL_DEFAULT_WRAP 72
@@ -1082,6 +1083,11 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
/* We can only do diffstat with a unique reference point */
if (origin)
show_diffstat(rev, origin, head);
+
+ if (rev->idiff_oid1) {
+ fprintf_ln(rev->diffopt.file, "%s", _("Interdiff:"));
+ show_interdiff(rev);
+ }
}
static const char *clean_message_id(const char *msg_id)
@@ -1448,6 +1454,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
struct base_tree_info bases;
int show_progress = 0;
struct progress *progress = NULL;
+ struct oid_array idiff_prev = OID_ARRAY_INIT;
const struct option builtin_format_patch_options[] = {
{ OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
@@ -1521,6 +1528,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
OPT__QUIET(&quiet, N_("don't print the patch filenames")),
OPT_BOOL(0, "progress", &show_progress,
N_("show progress while generating patches")),
+ OPT_CALLBACK(0, "interdiff", &idiff_prev, N_("rev"),
+ N_("show changes against <rev> in cover letter"),
+ parse_opt_object_name),
OPT_END()
};
@@ -1706,7 +1716,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
if (rev.pending.nr == 2) {
struct object_array_entry *o = rev.pending.objects;
if (oidcmp(&o[0].item->oid, &o[1].item->oid) == 0)
- return 0;
+ goto done;
}
get_patch_ids(&rev, &ids);
}
@@ -1730,7 +1740,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
}
if (nr == 0)
/* nothing to do */
- return 0;
+ goto done;
total = nr;
if (cover_letter == -1) {
if (config_cover_letter == COVER_AUTO)
@@ -1743,6 +1753,13 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
if (numbered)
rev.total = total + start_number - 1;
+ if (idiff_prev.nr) {
+ if (!cover_letter)
+ die(_("--interdiff requires --cover-letter"));
+ rev.idiff_oid1 = &idiff_prev.oid[idiff_prev.nr - 1];
+ rev.idiff_oid2 = get_commit_tree_oid(list[0]);
+ }
+
if (!signature) {
; /* --no-signature inhibits all signatures */
} else if (signature && signature != git_version_string) {
@@ -1860,6 +1877,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
string_list_clear(&extra_hdr, 0);
if (ignore_if_in_upstream)
free_patch_ids(&ids);
+
+done:
+ oid_array_clear(&idiff_prev);
return 0;
}
diff --git a/interdiff.c b/interdiff.c
new file mode 100644
index 0000000000..d0fac10c7c
--- /dev/null
+++ b/interdiff.c
@@ -0,0 +1,17 @@
+#include "cache.h"
+#include "commit.h"
+#include "revision.h"
+#include "interdiff.h"
+
+void show_interdiff(struct rev_info *rev)
+{
+ struct diff_options opts;
+
+ memcpy(&opts, &rev->diffopt, sizeof(opts));
+ opts.output_format = DIFF_FORMAT_PATCH;
+ diff_setup_done(&opts);
+
+ diff_tree_oid(rev->idiff_oid1, rev->idiff_oid2, "", &opts);
+ diffcore_std(&opts);
+ diff_flush(&opts);
+}
diff --git a/interdiff.h b/interdiff.h
new file mode 100644
index 0000000000..793c0144fe
--- /dev/null
+++ b/interdiff.h
@@ -0,0 +1,8 @@
+#ifndef INTERDIFF_H
+#define INTERDIFF_H
+
+struct rev_info;
+
+void show_interdiff(struct rev_info *);
+
+#endif
diff --git a/revision.h b/revision.h
index bf2239f876..61931fbac5 100644
--- a/revision.h
+++ b/revision.h
@@ -212,6 +212,10 @@ struct rev_info {
/* notes-specific options: which refs to show */
struct display_notes_opt notes_opt;
+ /* interdiff */
+ const struct object_id *idiff_oid1;
+ const struct object_id *idiff_oid2;
+
/* commit counts */
int count_left;
int count_right;
diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index 53880da7bb..57b46322aa 100755
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -1717,4 +1717,21 @@ test_expect_success 'format-patch --pretty=mboxrd' '
test_cmp expect actual
'
+test_expect_success 'interdiff: setup' '
+ git checkout -b boop master &&
+ test_commit fnorp blorp &&
+ test_commit fleep blorp
+'
+
+test_expect_success 'interdiff: cover-letter' '
+ sed "y/q/ /" >expect <<-\EOF &&
+ +fleep
+ --q
+ EOF
+ git format-patch --cover-letter --interdiff=boop~2 -1 boop &&
+ test_i18ngrep "^Interdiff:$" 0000-cover-letter.patch &&
+ sed "1,/^@@ /d; /^-- $/q" <0000-cover-letter.patch >actual &&
+ test_cmp expect actual
+'
+
test_done
--
2.18.0.345.g5c9ce644c3
Eric Sunshine
