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[PATCH v5 5/6] oddballs: send usage() help text to standard output

From
Junio C Hamano <gitster@pobox.com>
Date
Jan 17, 2025, 21:31 UTC
Message-ID
<20250117213148.3974552-6-gitster@pobox.com>
In-Reply-To
<20250117213148.3974552-1-gitster@pobox.com>

Using the show_usage_if_asked() helper we introduced earlier, fix callers of usage() that want to show the help text when explicitly asked by the end-user. The help text now goes to the standard output stream for them.

The callers in this step are oddballs in that their invocations of usage() are *not* guarded by

	if (argc == 2 && !strcmp(argv[1], "-h")
		usage(...);
There are (unnecessarily) being clever ones that do things like
	if (argc != 2 || !strcmp(argv[1], "-h")
		usage(...);

to say "I know I take only one argument, so argc != 2 is always an error regardless of what is in argv[]. Ah, by the way, even if argc is 2, "-h" is a request for usage text, so we do the same".

Some like "git var -h" just do not treat "-h" any specially, and let it take the same error code paths as a parameter error.

Now we cannot do the same, so these callers are rewrittin to do the show_usage_and_exit_if_asked() first and then handle the usage error the way they used to.

Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/credential.c     | 3 ++-
 builtin/fetch-pack.c     | 2 ++
 builtin/unpack-file.c    | 8 ++++++--
 builtin/upload-archive.c | 3 ++-
 builtin/var.c            | 1 +
 5 files changed, 13 insertions(+), 4 deletions(-)
diff --git a/builtin/credential.c b/builtin/credential.c
index 14c8c6608b..f6fc948123 100644
--- a/builtin/credential.c
+++ b/builtin/credential.c
@@ -18,7 +18,8 @@ int cmd_credential(int argc,
 
 	git_config(git_default_config, NULL);
 
-	if (argc != 2 || !strcmp(argv[1], "-h"))
+	show_usage_if_asked(argc, argv, usage_msg);
+	if (argc != 2)
 		usage(usage_msg);
 	op = argv[1];
 
diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c
index bed2816c2d..d07eec9e55 100644
--- a/builtin/fetch-pack.c
+++ b/builtin/fetch-pack.c
@@ -75,6 +75,8 @@ int cmd_fetch_pack(int argc,
 	list_objects_filter_init(&args.filter_options);
 	args.uploadpack = "git-upload-pack";
 
+	show_usage_if_asked(argc, argv, fetch_pack_usage);
+
 	for (i = 1; i < argc && *argv[i] == '-'; i++) {
 		const char *arg = argv[i];
 
diff --git a/builtin/unpack-file.c b/builtin/unpack-file.c
index 6da2825753..fb5fcbc40a 100644
--- a/builtin/unpack-file.c
+++ b/builtin/unpack-file.c
@@ -26,6 +26,9 @@ static char *create_temp_file(struct object_id *oid)
 	return path;
 }
 
+static const char usage_msg[] =
+"git unpack-file <blob>";
+
 int cmd_unpack_file(int argc,
 		    const char **argv,
 		    const char *prefix UNUSED,
@@ -33,8 +36,9 @@ int cmd_unpack_file(int argc,
 {
 	struct object_id oid;
 
-	if (argc != 2 || !strcmp(argv[1], "-h"))
-		usage("git unpack-file <blob>");
+	show_usage_if_asked(argc, argv, usage_msg);
+	if (argc != 2)
+		usage(usage_msg);
 	if (repo_get_oid(the_repository, argv[1], &oid))
 		die("Not a valid object name %s", argv[1]);
 
diff --git a/builtin/upload-archive.c b/builtin/upload-archive.c
index 9e9343f121..9d76a31c8f 100644
--- a/builtin/upload-archive.c
+++ b/builtin/upload-archive.c
@@ -27,7 +27,8 @@ int cmd_upload_archive_writer(int argc,
 	const char *arg_cmd = "argument ";
 	int ret;
 
-	if (argc != 2 || !strcmp(argv[1], "-h"))
+	show_usage_if_asked(argc, argv, upload_archive_usage);
+	if (argc != 2)
 		usage(upload_archive_usage);
 
 	if (!enter_repo(argv[1], 0))
diff --git a/builtin/var.c b/builtin/var.c
index 1449656cc9..46d40d6fba 100644
--- a/builtin/var.c
+++ b/builtin/var.c
@@ -221,6 +221,7 @@ int cmd_var(int argc,
 	const struct git_var *git_var;
 	char *val;
 
+	show_usage_if_asked(argc, argv, var_usage);
 	if (argc != 2)
 		usage(var_usage);
 
-- 
2.48.1-218-gc7e8be6a8f
Previous: Junio C HamanoNext: Junio C Hamano
Message 35 of 37 in “Send help text from "git cmd -h" to stdout”
  1. 0/6 Send help text from "git cmd -h" to stdoutJunio C Hamano, Jan 16, 2025
  2. 1/6 parse-options: add show_usage_help_and_exit_if_asked()Junio C Hamano, Jan 16, 2025
  3. 2/6 t0012: optionally check that "-h" output goes to stdoutJunio C Hamano, Jan 16, 2025
  4. 3/6 builtins: send usage_with_options() help text to standard outputJunio C Hamano, Jan 16, 2025
  5. 4/6 usage: add show_usage_and_exit_if_asked()Junio C Hamano, Jan 16, 2025
  6. Jeff KingJan 16, 2025
  7. Jeff KingJan 16, 2025
  8. Junio C HamanoJan 16, 2025
  9. Jeff KingJan 16, 2025
  10. Junio C HamanoJan 16, 2025
  11. 5/6 oddballs: send usage() help text to standard outputJunio C Hamano, Jan 16, 2025
  12. Jeff KingJan 16, 2025
  13. Junio C HamanoJan 16, 2025
  14. 6/6 builtin: send usage() help text to standard outputJunio C Hamano, Jan 16, 2025
  15. Junio C HamanoJan 16, 2025
  16. Junio C HamanoJan 16, 2025
  17. Jeff KingJan 16, 2025
  18. Junio C HamanoJan 16, 2025
  19. 0/6 Send help text from "git cmd -h" to stdoutJunio C Hamano, Jan 16, 2025
  20. 1/6 t0012: optionally check that "-h" output goes to stdoutJunio C Hamano, Jan 16, 2025
  21. 2/6 parse-options: add show_usage_with_options_if_asked()Junio C Hamano, Jan 16, 2025
  22. 3/6 usage: add show_usage_if_asked()Junio C Hamano, Jan 16, 2025
  23. Junio C HamanoJan 16, 2025
  24. Jeff KingJan 17, 2025
  25. 4/6 builtins: send usage_with_options() help text to standard outputJunio C Hamano, Jan 16, 2025
  26. 5/6 oddballs: send usage() help text to standard outputJunio C Hamano, Jan 16, 2025
  27. 6/6 builtin: send usage() help text to standard outputJunio C Hamano, Jan 16, 2025
  28. Jeff KingJan 17, 2025
  29. Junio C HamanoJan 17, 2025
  30. 0/6 Send help text from "git cmd -h" to stdoutJunio C Hamano, Jan 17, 2025
  31. 1/6 t0012: optionally check that "-h" output goes to stdoutJunio C Hamano, Jan 17, 2025
  32. 2/6 parse-options: add show_usage_with_options_if_asked()Junio C Hamano, Jan 17, 2025
  33. 3/6 usage: add show_usage_if_asked()Junio C Hamano, Jan 17, 2025
  34. 4/6 builtins: send usage_with_options() help text to standard outputJunio C Hamano, Jan 17, 2025
  35. 5/6 oddballs: send usage() help text to standard outputJunio C Hamano, Jan 17, 2025
  36. 6/6 builtin: send usage() help text to standard outputJunio C Hamano, Jan 17, 2025
  37. Jeff KingJan 18, 2025

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