revision: handle pseudo-opts in --stdin mode

While both git-rev-list(1) and git-log(1) support `--stdin`, it only
accepts commits and files. Most notably, it is impossible to pass any of
the pseudo-opts like `--all`, `--glob=` or others via stdin.

This makes it hard to use this function in certain scripted scenarios,
like when one wants to support queries against specific revisions, but
also against reference patterns. While this is theoretically possible by
using arguments, this may run into issues once we hit platform limits
with sufficiently large queries. And because `--stdin` cannot handle
pseudo-opts, the only alternative would be to use a mixture of arguments
and standard input, which is cumbersome.

Implement support for handling pseudo-opts in both commands to support
this usecase better. One notable restriction here is that `--stdin` only
supports "stuck" arguments in the form of `--glob=foo`. This is because
"unstuck" arguments would also require us to read the next line, which
would add quite some complexity to the code. This restriction should be
fine for scripted usage though.

Signed-off-by: Patrick Steinhardt <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: pks-t

Documentation/rev-list-options.txt

@@ -236,10 +236,11 @@ ifndef::git-rev-list[]
 endif::git-rev-list[]
 
 --stdin::
-	In addition to the '<commit>' listed on the command
-	line, read them from the standard input. If a `--` separator is
-	seen, stop reading commits and start reading paths to limit the
-	result.
+	In addition to getting arguments from the command line, read
+	them for standard input as well. This accepts commits and
+	pseudo-options like `--all` and `--glob=`. When a `--` separator
+	is seen, the following input is treated as paths and used to
+	limit the result.
 
 ifdef::git-rev-list[]
 --quiet::

revision.c

@@ -2784,10 +2784,12 @@ static int handle_revision_pseudo_opt(struct rev_info *revs,
 }
 
 static void read_revisions_from_stdin(struct rev_info *revs,
-				      struct strvec *prune)
+				      struct strvec *prune,
+				      int *flags)
 {
 	struct strbuf sb;
 	int seen_dashdash = 0;
+	int seen_end_of_options = 0;
 	int save_warning;
 
 	save_warning = warn_on_object_refname_ambiguity;
@@ -2803,8 +2805,19 @@ static void read_revisions_from_stdin(struct rev_info *revs,
 			break;
 		}
 
-		if (sb.buf[0] == '-')
-			die("options not supported in --stdin mode");
+		if (!seen_end_of_options && sb.buf[0] == '-') {
+			const char *argv[] = { sb.buf, NULL };
+
+			if (!strcmp(sb.buf, "--end-of-options")) {
+				seen_end_of_options = 1;
+				continue;
+			}
+
+			if (handle_revision_pseudo_opt(revs, argv, flags) > 0)
+				continue;
+
+			die(_("invalid option '%s' in --stdin mode"), sb.buf);
+		}
 
 		if (handle_revision_arg(sb.buf, revs, 0,
 					REVARG_CANNOT_BE_FILENAME))
@@ -2889,7 +2902,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
 				}
 				if (revs->read_from_stdin++)
 					die("--stdin given twice?");
-				read_revisions_from_stdin(revs, &prune_data);
+				read_revisions_from_stdin(revs, &prune_data, &flags);
 				continue;
 			}
 

t/t6017-rev-list-stdin.sh

@@ -48,7 +48,9 @@ test_expect_success setup '
 			git add file-$i &&
 			test_tick &&
 			git commit -m side-$i || exit
-		done
+		done &&
+
+		git update-ref refs/heads/-dashed-branch HEAD
 	)
 '
 
@@ -60,6 +62,12 @@ check side-1 ^side-7 -- file-2
 check side-3 ^side-4 -- file-3
 check side-3 ^side-2
 check side-3 ^side-2 -- file-1
+check --all
+check --all --not --branches
+check --glob=refs/heads
+check --glob=refs/heads --
+check --glob=refs/heads -- file-1
+check --end-of-options -dashed-branch
 
 test_expect_success 'not only --stdin' '
 	cat >expect <<-EOF &&
@@ -78,4 +86,45 @@ test_expect_success 'not only --stdin' '
 	test_cmp expect actual
 '
 
+test_expect_success 'pseudo-opt with missing value' '
+	cat >input <<-EOF &&
+	--glob
+	refs/heads
+	EOF
+
+	cat >expect <<-EOF &&
+	fatal: Option ${SQ}--glob${SQ} requires a value
+	EOF
+
+	test_must_fail git rev-list --stdin <input 2>error &&
+	test_cmp expect error
+'
+
+test_expect_success 'pseudo-opt with invalid value' '
+	cat >input <<-EOF &&
+	--no-walk=garbage
+	EOF
+
+	cat >expect <<-EOF &&
+	error: invalid argument to --no-walk
+	fatal: invalid option ${SQ}--no-walk=garbage${SQ} in --stdin mode
+	EOF
+
+	test_must_fail git rev-list --stdin <input 2>error &&
+	test_cmp expect error
+'
+
+test_expect_success 'unknown option without --end-of-options' '
+	cat >input <<-EOF &&
+	-dashed-branch
+	EOF
+
+	cat >expect <<-EOF &&
+	fatal: invalid option ${SQ}-dashed-branch${SQ} in --stdin mode
+	EOF
+
+	test_must_fail git rev-list --stdin <input 2>error &&
+	test_cmp expect error
+'
+
 test_done