doc txt & -h consistency: make "annotate" consistent

The cmd_blame() already detected whether it was processing "blame" or
"annotate", but it didn't adjust its usage output accordingly. Let's
do that.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-annotate.txt

@@ -8,7 +8,7 @@ git-annotate - Annotate file lines with commit information
 SYNOPSIS
 --------
 [verse]
-'git annotate' [<options>] <file> [<revision>]
+'git annotate' [<options>] [<rev-opts>] [<rev>] [--] <file>
 
 DESCRIPTION
 -----------

builtin/blame.c

@@ -30,6 +30,7 @@
 #include "tag.h"
 
 static char blame_usage[] = N_("git blame [<options>] [<rev-opts>] [<rev>] [--] <file>");
+static char annotate_usage[] = N_("git annotate [<options>] [<rev-opts>] [<rev>] [--] <file>");
 
 static const char *blame_opt_usage[] = {
 	blame_usage,
@@ -38,6 +39,13 @@ static const char *blame_opt_usage[] = {
 	NULL
 };
 
+static const char *annotate_opt_usage[] = {
+	annotate_usage,
+	"",
+	N_("<rev-opts> are documented in git-rev-list(1)"),
+	NULL
+};
+
 static int longest_file;
 static int longest_author;
 static int max_orig_digits;
@@ -899,6 +907,8 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 	long anchor;
 	const int hexsz = the_hash_algo->hexsz;
 	long num_lines = 0;
+	const char *str_usage = cmd_is_annotate ? annotate_usage : blame_usage;
+	const char **opt_usage = cmd_is_annotate ? annotate_opt_usage : blame_opt_usage;
 
 	setup_default_color_by_age();
 	git_config(git_blame_config, &output_option);
@@ -914,7 +924,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 	parse_options_start(&ctx, argc, argv, prefix, options,
 			    PARSE_OPT_KEEP_DASHDASH | PARSE_OPT_KEEP_ARGV0);
 	for (;;) {
-		switch (parse_options_step(&ctx, options, blame_opt_usage)) {
+		switch (parse_options_step(&ctx, options, opt_usage)) {
 		case PARSE_OPT_NON_OPTION:
 		case PARSE_OPT_UNKNOWN:
 			break;
@@ -934,7 +944,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 			ctx.argv[0] = "--children";
 			reverse = 1;
 		}
-		parse_revision_opt(&revs, &ctx, options, blame_opt_usage);
+		parse_revision_opt(&revs, &ctx, options, opt_usage);
 	}
 parse_done:
 	revision_opts_finish(&revs);
@@ -1040,7 +1050,7 @@ parse_done:
 		switch (argc - dashdash_pos - 1) {
 		case 2: /* (1b) */
 			if (argc != 4)
-				usage_with_options(blame_opt_usage, options);
+				usage_with_options(opt_usage, options);
 			/* reorder for the new way: <rev> -- <path> */
 			argv[1] = argv[3];
 			argv[3] = argv[2];
@@ -1051,11 +1061,11 @@ parse_done:
 			argv[argc] = NULL;
 			break;
 		default:
-			usage_with_options(blame_opt_usage, options);
+			usage_with_options(opt_usage, options);
 		}
 	} else {
 		if (argc < 2)
-			usage_with_options(blame_opt_usage, options);
+			usage_with_options(opt_usage, options);
 		if (argc == 3 && is_a_rev(argv[argc - 1])) { /* (2b) */
 			path = add_prefix(prefix, argv[1]);
 			argv[1] = argv[2];
@@ -1113,7 +1123,7 @@ parse_done:
 				    nth_line_cb, &sb, lno, anchor,
 				    &bottom, &top, sb.path,
 				    the_repository->index))
-			usage(blame_usage);
+			usage(str_usage);
 		if ((!lno && (top || bottom)) || lno < bottom)
 			die(Q_("file %s has only %lu line",
 			       "file %s has only %lu lines",