Merge branch 'bc/rev-list-without-commit-line'

"git rev-list" learns to omit the "commit <object-name>" header
lines from the output with the `--no-commit-header` option.

* bc/rev-list-without-commit-line:
  rev-list: add option for --pretty=format without header

Documentation/rev-list-options.txt

@@ -1064,6 +1064,14 @@ ifdef::git-rev-list[]
 --header::
 	Print the contents of the commit in raw-format; each record is
 	separated with a NUL character.
+
+--no-commit-header::
+	Suppress the header line containing "commit" and the object ID printed before
+	the specified format.  This has no effect on the built-in formats; only custom
+	formats are affected.
+
+--commit-header::
+	Overrides a previous `--no-commit-header`.
 endif::git-rev-list[]
 
 --parents::

builtin/rev-list.c

@@ -127,13 +127,15 @@ static void show_commit(struct commit *commit, void *data)
 	if (info->header_prefix)
 		fputs(info->header_prefix, stdout);
 
-	if (!revs->graph)
-		fputs(get_revision_mark(revs, commit), stdout);
-	if (revs->abbrev_commit && revs->abbrev)
-		fputs(find_unique_abbrev(&commit->object.oid, revs->abbrev),
-		      stdout);
-	else
-		fputs(oid_to_hex(&commit->object.oid), stdout);
+	if (revs->include_header) {
+		if (!revs->graph)
+			fputs(get_revision_mark(revs, commit), stdout);
+		if (revs->abbrev_commit && revs->abbrev)
+			fputs(find_unique_abbrev(&commit->object.oid, revs->abbrev),
+			      stdout);
+		else
+			fputs(oid_to_hex(&commit->object.oid), stdout);
+	}
 	if (revs->print_parents) {
 		struct commit_list *parents = commit->parents;
 		while (parents) {
@@ -153,7 +155,7 @@ static void show_commit(struct commit *commit, void *data)
 	show_decorations(revs, commit);
 	if (revs->commit_format == CMIT_FMT_ONELINE)
 		putchar(' ');
-	else
+	else if (revs->include_header)
 		putchar('\n');
 
 	if (revs->verbose_header) {
@@ -512,6 +514,7 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 	repo_init_revisions(the_repository, &revs, prefix);
 	revs.abbrev = DEFAULT_ABBREV;
 	revs.commit_format = CMIT_FMT_UNSPECIFIED;
+	revs.include_header = 1;
 
 	/*
 	 * Scan the argument list before invoking setup_revisions(), so that we
@@ -627,6 +630,16 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 			continue;
 		}
 
+		if (!strcmp(arg, ("--commit-header"))) {
+			revs.include_header = 1;
+			continue;
+		}
+
+		if (!strcmp(arg, ("--no-commit-header"))) {
+			revs.include_header = 0;
+			continue;
+		}
+
 		if (!strcmp(arg, "--disk-usage")) {
 			show_disk_usage = 1;
 			info.flags |= REV_LIST_QUIET;
@@ -636,10 +649,12 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 		usage(rev_list_usage);
 
 	}
+	if (revs.commit_format != CMIT_FMT_USERFORMAT)
+		revs.include_header = 1;
 	if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
 		/* The command line has a --pretty  */
 		info.hdr_termination = '\n';
-		if (revs.commit_format == CMIT_FMT_ONELINE)
+		if (revs.commit_format == CMIT_FMT_ONELINE || !revs.include_header)
 			info.header_prefix = "";
 		else
 			info.header_prefix = "commit ";

revision.h

@@ -215,7 +215,8 @@ struct rev_info {
 			missing_newline:1,
 			date_mode_explicit:1,
 			preserve_subject:1,
-			encode_email_headers:1;
+			encode_email_headers:1,
+			include_header:1;
 	unsigned int	disable_stdin:1;
 	/* --show-linear-break */
 	unsigned int	track_linear:1,

t/t6006-rev-list-format.sh

@@ -41,22 +41,59 @@ test_expect_success 'setup' '
 	echo "$added_iso88591" | git commit -F - &&
 	head1=$(git rev-parse --verify HEAD) &&
 	head1_short=$(git rev-parse --verify --short $head1) &&
+	head1_short4=$(git rev-parse --verify --short=4 $head1) &&
 	tree1=$(git rev-parse --verify HEAD:) &&
 	tree1_short=$(git rev-parse --verify --short $tree1) &&
 	echo "$changed" > foo &&
 	echo "$changed_iso88591" | git commit -a -F - &&
 	head2=$(git rev-parse --verify HEAD) &&
 	head2_short=$(git rev-parse --verify --short $head2) &&
+	head2_short4=$(git rev-parse --verify --short=4 $head2) &&
 	tree2=$(git rev-parse --verify HEAD:) &&
 	tree2_short=$(git rev-parse --verify --short $tree2) &&
 	git config --unset i18n.commitEncoding
 '
 
-# usage: test_format name format_string [failure] <expected_output
+# usage: test_format [argument...] name format_string [failure] <expected_output
 test_format () {
+	local args=
+	while true
+	do
+		case "$1" in
+		--*)
+			args="$args $1"
+			shift;;
+		*)
+			break;;
+		esac
+	done
 	cat >expect.$1
 	test_expect_${3:-success} "format $1" "
-		git rev-list --pretty=format:'$2' main >output.$1 &&
+		git rev-list $args --pretty=format:'$2' main >output.$1 &&
+		test_cmp expect.$1 output.$1
+	"
+}
+
+# usage: test_pretty [argument...] name format_name [failure] <expected_output
+test_pretty () {
+	local args=
+	while true
+	do
+		case "$1" in
+		--*)
+			args="$args $1"
+			shift;;
+		*)
+			break;;
+		esac
+	done
+	cat >expect.$1
+	test_expect_${3:-success} "pretty $1 (without --no-commit-header)" "
+		git rev-list $args --pretty='$2' main >output.$1 &&
+		test_cmp expect.$1 output.$1
+	"
+	test_expect_${3:-success} "pretty $1 (with --no-commit-header)" "
+		git rev-list $args --no-commit-header --pretty='$2' main >output.$1 &&
 		test_cmp expect.$1 output.$1
 	"
 }
@@ -93,6 +130,20 @@ $head1
 $head1_short
 EOF
 
+test_format --no-commit-header hash-no-header %H%n%h <<EOF
+$head2
+$head2_short
+$head1
+$head1_short
+EOF
+
+test_format --abbrev-commit --abbrev=0 --no-commit-header hash-no-header-abbrev %H%n%h <<EOF
+$head2
+$head2_short4
+$head1
+$head1_short4
+EOF
+
 test_format tree %T%n%t <<EOF
 commit $head2
 $tree2
@@ -181,6 +232,31 @@ $added
 
 EOF
 
+test_format --no-commit-header raw-body-no-header %B <<EOF
+$changed
+
+$added
+
+EOF
+
+test_pretty oneline oneline <<EOF
+$head2 $changed
+$head1 $added
+EOF
+
+test_pretty short short <<EOF
+commit $head2
+Author: $GIT_AUTHOR_NAME <$GIT_AUTHOR_EMAIL>
+
+    $changed
+
+commit $head1
+Author: $GIT_AUTHOR_NAME <$GIT_AUTHOR_EMAIL>
+
+    $added
+
+EOF
+
 test_expect_success 'basic colors' '
 	cat >expect <<-EOF &&
 	commit $head2