ls-files: pass through safe options for --recurse-submodules

Pass through some known-safe options when recursing into submodules.
(--cached, -v, -t, -z, --debug, --eol)

Signed-off-by: Brandon Williams <bmwill@google.com>
Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/ls-files.c

@@ -30,6 +30,7 @@ static int line_terminator = '\n';
 static int debug_mode;
 static int show_eol;
 static int recurse_submodules;
+static struct argv_array submodules_options = ARGV_ARRAY_INIT;
 
 static const char *prefix;
 static const char *super_prefix;
@@ -168,6 +169,25 @@ static void show_killed_files(struct dir_struct *dir)
 	}
 }
 
+/*
+ * Compile an argv_array with all of the options supported by --recurse_submodules
+ */
+static void compile_submodule_options(const struct dir_struct *dir, int show_tag)
+{
+	if (line_terminator == '\0')
+		argv_array_push(&submodules_options, "-z");
+	if (show_tag)
+		argv_array_push(&submodules_options, "-t");
+	if (show_valid_bit)
+		argv_array_push(&submodules_options, "-v");
+	if (show_cached)
+		argv_array_push(&submodules_options, "--cached");
+	if (show_eol)
+		argv_array_push(&submodules_options, "--eol");
+	if (debug_mode)
+		argv_array_push(&submodules_options, "--debug");
+}
+
 /**
  * Recursively call ls-files on a submodule
  */
@@ -182,6 +202,9 @@ static void show_gitlink(const struct cache_entry *ce)
 	argv_array_push(&cp.args, "ls-files");
 	argv_array_push(&cp.args, "--recurse-submodules");
 
+	/* add supported options */
+	argv_array_pushv(&cp.args, submodules_options.argv);
+
 	cp.git_cmd = 1;
 	cp.dir = ce->name;
 	status = run_command(&cp);
@@ -567,11 +590,12 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
 	if (require_work_tree && !is_inside_work_tree())
 		setup_work_tree();
 
+	if (recurse_submodules)
+		compile_submodule_options(&dir, show_tag);
+
 	if (recurse_submodules &&
 	    (show_stage || show_deleted || show_others || show_unmerged ||
-	     show_killed || show_modified || show_resolve_undo ||
+	     show_killed || show_modified || show_resolve_undo || with_tree))
-	     show_valid_bit || show_tag || show_eol || with_tree ||
-	     (line_terminator == '\0')))
 		die("ls-files --recurse-submodules unsupported mode");
 
 	if (recurse_submodules && error_unmatch)

t/t3007-ls-files-recurse-submodules.sh

@@ -34,6 +34,18 @@ test_expect_success 'ls-files correctly outputs files in submodule' '
 	test_cmp expect actual
 '
 
+test_expect_success 'ls-files correctly outputs files in submodule with -z' '
+	lf_to_nul >expect <<-\EOF &&
+	.gitmodules
+	a
+	b/b
+	submodule/c
+	EOF
+
+	git ls-files --recurse-submodules -z >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'ls-files does not output files not added to a repo' '
 	cat >expect <<-\EOF &&
 	.gitmodules
@@ -86,15 +98,11 @@ test_incompatible_with_recurse_submodules () {
 	"
 }
 
-test_incompatible_with_recurse_submodules -z
-test_incompatible_with_recurse_submodules -v
-test_incompatible_with_recurse_submodules -t
 test_incompatible_with_recurse_submodules --deleted
 test_incompatible_with_recurse_submodules --modified
 test_incompatible_with_recurse_submodules --others
 test_incompatible_with_recurse_submodules --stage
 test_incompatible_with_recurse_submodules --killed
 test_incompatible_with_recurse_submodules --unmerged
-test_incompatible_with_recurse_submodules --eol
 
 test_done