Add a format placeholder for describe output. Implement it by actually
calling git describe, which is simple and guarantees correctness. It's
intended to be used with $Format:...$ in files with the attribute
export-subst and git archive. It can also be used with git log etc.,
even though that's going to be slow due to the fork for each commit.
Suggested-by: Eli Schwartz <eschwartz@xxxxxxxxxxxxx>
Signed-off-by: René Scharfe <l.s.r@xxxxxx>
---
Documentation/pretty-formats.txt | 2 ++
pretty.c | 17 +++++++++++++++++
t/t4205-log-pretty-formats.sh | 10 ++++++++++
3 files changed, 29 insertions(+)
diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt
index 6b59e28d44..bb8c05bc21 100644
--- a/Documentation/pretty-formats.txt
+++ b/Documentation/pretty-formats.txt
@@ -208,6 +208,8 @@ The placeholders are:
'%cs':: committer date, short format (`YYYY-MM-DD`)
'%d':: ref names, like the --decorate option of linkgit:git-log[1]
'%D':: ref names without the " (", ")" wrapping.
+'%(describe)':: human-readable name, like linkgit:git-describe[1];
+ empty string for undescribable commits
'%S':: ref name given on the command line by which the commit was reached
(like `git log --source`), only works with `git log`
'%e':: encoding
diff --git a/pretty.c b/pretty.c
index b4ff3f602f..a0c427fb61 100644
--- a/pretty.c
+++ b/pretty.c
@@ -12,6 +12,7 @@
#include "reflog-walk.h"
#include "gpg-interface.h"
#include "trailer.h"
+#include "run-command.h"
static char *user_format;
static struct cmt_fmt_map {
@@ -1214,6 +1215,22 @@ static size_t format_commit_one(struct strbuf *sb, /* in UTF-8 */
return parse_padding_placeholder(placeholder, c);
}
+ if (skip_prefix(placeholder, "(describe)", &arg)) {
+ struct child_process cmd = CHILD_PROCESS_INIT;
+ struct strbuf out = STRBUF_INIT;
+ struct strbuf err = STRBUF_INIT;
+
+ cmd.git_cmd = 1;
+ strvec_push(&cmd.args, "describe");
+ strvec_push(&cmd.args, oid_to_hex(&commit->object.oid));
+ pipe_command(&cmd, NULL, 0, &out, 0, &err, 0);
+ strbuf_rtrim(&out);
+ strbuf_addbuf(sb, &out);
+ strbuf_release(&out);
+ strbuf_release(&err);
+ return arg - placeholder;
+ }
+
/* these depend on the commit */
if (!commit->object.parsed)
parse_object(the_repository, &commit->object.oid);
diff --git a/t/t4205-log-pretty-formats.sh b/t/t4205-log-pretty-formats.sh
index 749bc1431a..5a44fa447d 100755
--- a/t/t4205-log-pretty-formats.sh
+++ b/t/t4205-log-pretty-formats.sh
@@ -962,4 +962,14 @@ test_expect_success 'log --pretty=reference is colored appropriately' '
test_cmp expect actual
'
+test_expect_success '%(describe) vs git describe' '
+ git log --format="%H" | while read hash
+ do
+ echo "$hash $(git describe $hash)"
+ done >expect &&
+ git log --format="%H %(describe)" >actual 2>err &&
+ test_cmp expect actual &&
+ test_must_be_empty err
+'
+
test_done
--
2.30.1
