1 files changed, 63 insertions, 32 deletions

diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 8735620813..895292074a 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -648,6 +648,8 @@ static int batch_option_callback(const struct option *opt,
 int cmd_cat_file(int argc, const char **argv, const char *prefix)
 {
 	int opt = 0;
+	int opt_cw = 0;
+	int opt_epts = 0;
 	const char *exp_type = NULL, *obj_name = NULL;
 	struct batch_options batch = {0};
 	int unknown_type = 0;
@@ -701,45 +703,74 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 	batch.buffer_output = -1;
 
 	argc = parse_options(argc, argv, prefix, options, usage, 0);
-	if (argc && batch.enabled)
-		usage_with_options(usage, options);
-	if (opt == 'b') {
-		batch.all_objects = 1;
-	} else if (opt) {
-		if (batch.enabled && (opt == 'c' || opt == 'w'))
-			batch.cmdmode = opt;
-		else if (argc == 1)
-			obj_name = argv[0];
-		else
-			usage_with_options(usage, options);
-	} else if (!opt && !batch.enabled) {
-		if (argc == 2) {
-			exp_type = argv[0];
-			obj_name = argv[1];
-		} else
-			usage_with_options(usage, options);
-	} else if (batch.enabled && batch.cmdmode != opt)
-		usage_with_options(usage, options);
+	opt_cw = (opt == 'c' || opt == 'w');
+	opt_epts = (opt == 'e' || opt == 'p' || opt == 't' || opt == 's');
 
-	if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
-		usage_with_options(usage, options);
-	}
-
-	if (force_path && opt != 'c' && opt != 'w') {
-		error("--path=<path> needs --textconv or --filters");
-		usage_with_options(usage, options);
-	}
+	/* --batch-all-objects? */
+	if (opt == 'b')
+		batch.all_objects = 1;
 
-	if (force_path && batch.enabled) {
-		error("--path=<path> incompatible with --batch");
-		usage_with_options(usage, options);
-	}
+	/* Option compatibility */
+	if (force_path && !opt_cw)
+		usage_msg_optf(_("'%s=<%s>' needs '%s' or '%s'"),
+			       usage, options,
+			       "--path", _("path|tree-ish"), "--filters",
+			       "--textconv");
 
+	/* Option compatibility with batch mode */
+	if (batch.enabled)
+		;
+	else if (batch.follow_symlinks)
+		usage_msg_optf(_("'%s' requires a batch mode"), usage, options,
+			       "--follow_symlinks");
+	else if (batch.buffer_output >= 0)
+		usage_msg_optf(_("'%s' requires a batch mode"), usage, options,
+			       "--buffer");
+	else if (batch.all_objects)
+		usage_msg_optf(_("'%s' requires a batch mode"), usage, options,
+			       "--batch-all-objects");
+
+	/* Batch defaults */
 	if (batch.buffer_output < 0)
 		batch.buffer_output = batch.all_objects;
 
-	if (batch.enabled)
+	/* Return early if we're in batch mode? */
+	if (batch.enabled) {
+		if (opt_cw)
+			batch.cmdmode = opt;
+		else if (opt && opt != 'b')
+			usage_msg_optf(_("'-%c' is incompatible with batch mode"),
+				       usage, options, opt);
+		else if (argc)
+			usage_msg_opt(_("batch modes take no arguments"), usage,
+				      options);
+
 		return batch_objects(&batch);
+	}
+
+	if (opt) {
+		if (!argc && opt == 'c')
+			usage_msg_optf(_("<rev> required with '%s'"),
+				       usage, options, "--textconv");
+		else if (!argc && opt == 'w')
+			usage_msg_optf(_("<rev> required with '%s'"),
+				       usage, options, "--filters");
+		else if (!argc && opt_epts)
+			usage_msg_optf(_("<object> required with '-%c'"),
+				       usage, options, opt);
+		else if (argc == 1)
+			obj_name = argv[0];
+		else
+			usage_msg_opt(_("too many arguments"), usage, options);
+	} else if (!argc) {
+		usage_with_options(usage, options);
+	} else if (argc != 2) {
+		usage_msg_optf(_("only two arguments allowed in <type> <object> mode, not %d"),
+			      usage, options, argc);
+	} else if (argc) {
+		exp_type = argv[0];
+		obj_name = argv[1];
+	}
 
 	if (unknown_type && opt != 't' && opt != 's')
 		die("git cat-file --allow-unknown-type: use with -s or -t");