Merge branch 'lo/repo-info-keys' into jch

"git repo info" learns "--keys" action to list known keys.

* lo/repo-info-keys:
  repo: add new flag --keys to git-repo-info
  repo: rename the output format "keyvalue" to "lines"

Documentation/git-repo.adoc

@@ -8,8 +8,9 @@ git-repo - Retrieve information about the repository
 SYNOPSIS
 --------
 [synopsis]
-git repo info [--format=(keyvalue|nul) | -z] [--all | <key>...]
-git repo structure [--format=(table|keyvalue|nul) | -z]
+git repo info [--format=(lines|nul) | -z] [--all | <key>...]
+git repo info --keys [--format=(lines|nul) | -z]
+git repo structure [--format=(table|lines|nul) | -z]
 
 DESCRIPTION
 -----------
@@ -19,7 +20,7 @@ THIS COMMAND IS EXPERIMENTAL. THE BEHAVIOR MAY CHANGE.
 
 COMMANDS
 --------
-`info [--format=(keyvalue|nul) | -z] [--all | <key>...]`::
+`info [--format=(lines|nul) | -z] [--all | <key>...]`::
 	Retrieve metadata-related information about the current repository. Only
 	the requested data will be returned based on their keys (see "INFO KEYS"
 	section below).
@@ -30,21 +31,32 @@ requested. The `--all` flag requests the values for all the available keys.
 The output format can be chosen through the flag `--format`. Two formats are
 supported:
 +
-`keyvalue`:::
+
+`lines`:::
 	output key-value pairs one per line using the `=` character as
 	the delimiter between the key and the value. Values containing "unusual"
 	characters are quoted as explained for the configuration variable
 	`core.quotePath` (see linkgit:git-config[1]). This is the default.
 
 `nul`:::
-	similar to `keyvalue`, but using a newline character as the delimiter
+	similar to `lines`, but using a newline character as the delimiter
 	between the key and the value and using a NUL character after each value.
 	This format is better suited for being parsed by another applications than
-	`keyvalue`. Unlike in the `keyvalue` format, the values are never quoted.
+	`lines`. Unlike in the `lines` format, the values are never quoted.
 +
 `-z` is an alias for `--format=nul`.
 
-`structure [--format=(table|keyvalue|nul) | -z]`::
+`info --keys [--format=(lines|nul) | -z]`::
+	List all the available keys, one per line. The output format can be chosen
+	through the flag `--format`. The following formats are supported:
++
+`lines`:::
+	Output the keys one per line. This is the default.
+
+`nul`:::
+	Similar to `lines`, but using a _NUL_ character after each value.
+
+`structure [--format=(table|lines|nul) | -z]`::
 	Retrieve statistics about the current repository structure. The
 	following kinds of information are reported:
 +
@@ -61,17 +73,17 @@ supported:
 	change and is not intended for machine parsing. This is the default
 	format.
 
-`keyvalue`:::
+`lines`:::
 	Each line of output contains a key-value pair for a repository stat.
 	The '=' character is used to delimit between the key and the value.
 	Values containing "unusual" characters are quoted as explained for the
 	configuration variable `core.quotePath` (see linkgit:git-config[1]).
 
 `nul`:::
-	Similar to `keyvalue`, but uses a NUL character to delimit between
+	Similar to `lines`, but uses a NUL character to delimit between
 	key-value pairs instead of a newline. Also uses a newline character as
 	the delimiter between the key and value instead of '='. Unlike the
-	`keyvalue` format, values containing "unusual" characters are never
+	`lines` format, values containing "unusual" characters are never
 	quoted.
 +
 `-z` is an alias for `--format=nul`.

builtin/repo.c

@@ -17,8 +17,9 @@
 #include "utf8.h"
 
 static const char *const repo_usage[] = {
-	"git repo info [--format=(keyvalue|nul) | -z] [--all | <key>...]",
-	"git repo structure [--format=(table|keyvalue|nul) | -z]",
+	"git repo info [--format=(lines|nul) | -z] [--all | <key>...]",
+	"git repo info --keys [--format=(lines|nul) | -z]",
+	"git repo structure [--format=(table|lines|nul) | -z]",
 	NULL
 };
 
@@ -26,7 +27,7 @@ typedef int get_value_fn(struct repository *repo, struct strbuf *buf);
 
 enum output_format {
 	FORMAT_TABLE,
-	FORMAT_KEYVALUE,
+	FORMAT_NEWLINE_TERMINATED,
 	FORMAT_NUL_TERMINATED,
 };
 
@@ -91,7 +92,7 @@ static void print_field(enum output_format format, const char *key,
 			const char *value)
 {
 	switch (format) {
-	case FORMAT_KEYVALUE:
+	case FORMAT_NEWLINE_TERMINATED:
 		printf("%s=", key);
 		quote_c_style(value, NULL, stdout, 0);
 		putchar('\n');
@@ -148,6 +149,29 @@ static int print_all_fields(struct repository *repo,
 	return 0;
 }
 
+static int print_keys(enum output_format format)
+{
+	char sep;
+
+	switch (format) {
+	case FORMAT_NEWLINE_TERMINATED:
+		sep = '\n';
+		break;
+	case FORMAT_NUL_TERMINATED:
+		sep = '\0';
+		break;
+	default:
+		die(_("--keys can only be used with --format=lines or --format=nul"));
+	}
+
+	for (size_t i = 0; i < ARRAY_SIZE(repo_info_fields); i++) {
+		const struct field *field = &repo_info_fields[i];
+		printf("%s%c", field->key, sep);
+	}
+
+	return 0;
+}
+
 static int parse_format_cb(const struct option *opt,
 			   const char *arg, int unset UNUSED)
 {
@@ -157,8 +181,8 @@ static int parse_format_cb(const struct option *opt,
 		*format = FORMAT_NUL_TERMINATED;
 	else if (!strcmp(arg, "nul"))
 		*format = FORMAT_NUL_TERMINATED;
-	else if (!strcmp(arg, "keyvalue"))
-		*format = FORMAT_KEYVALUE;
+	else if (!strcmp(arg, "lines"))
+		*format = FORMAT_NEWLINE_TERMINATED;
 	else if (!strcmp(arg, "table"))
 		*format = FORMAT_TABLE;
 	else
@@ -170,8 +194,9 @@ static int parse_format_cb(const struct option *opt,
 static int cmd_repo_info(int argc, const char **argv, const char *prefix,
 			 struct repository *repo)
 {
-	enum output_format format = FORMAT_KEYVALUE;
+	enum output_format format = FORMAT_NEWLINE_TERMINATED;
 	int all_keys = 0;
+	int show_keys = 0;
 	struct option options[] = {
 		OPT_CALLBACK_F(0, "format", &format, N_("format"),
 			       N_("output format"),
@@ -181,11 +206,19 @@ static int cmd_repo_info(int argc, const char **argv, const char *prefix,
 			       PARSE_OPT_NONEG | PARSE_OPT_NOARG,
 			       parse_format_cb),
 		OPT_BOOL(0, "all", &all_keys, N_("print all keys/values")),
+		OPT_BOOL(0, "keys", &show_keys, N_("show keys")),
 		OPT_END()
 	};
 
 	argc = parse_options(argc, argv, prefix, options, repo_usage, 0);
-	if (format != FORMAT_KEYVALUE && format != FORMAT_NUL_TERMINATED)
+
+	if (show_keys && (all_keys || argc))
+		die(_("--keys cannot be used with a <key> or --all"));
+
+	if (show_keys)
+		return print_keys(format);
+
+	if (format != FORMAT_NEWLINE_TERMINATED && format != FORMAT_NUL_TERMINATED)
 		die(_("unsupported output format"));
 
 	if (all_keys && argc)
@@ -671,7 +704,7 @@ static int cmd_repo_structure(int argc, const char **argv, const char *prefix,
 		stats_table_setup_structure(&table, &stats);
 		stats_table_print_structure(&table);
 		break;
-	case FORMAT_KEYVALUE:
+	case FORMAT_NEWLINE_TERMINATED:
 		structure_keyvalue_print(&stats, '=', '\n');
 		break;
 	case FORMAT_NUL_TERMINATED:

t/t1900-repo.sh

@@ -4,15 +4,6 @@ test_description='test git repo-info'
 
 . ./test-lib.sh
 
-# git-repo-info keys. It must contain the same keys listed in the const
-# repo_info_fields, in lexicographical order.
-REPO_INFO_KEYS='
-	layout.bare
-	layout.shallow
-	object.format
-	references.format
-'
-
 # Test whether a key-value pair is correctly returned
 #
 # Usage: test_repo_info <label> <init command> <repo_name> <key> <expected value>
@@ -34,7 +25,7 @@ test_repo_info () {
 		eval "$init_command $repo_name"
 	'
 
-	test_expect_success "keyvalue: $label" '
+	test_expect_success "lines: $label" '
 		echo "$key=$expected_value" > expect &&
 		git -C "$repo_name" repo info "$key" >actual &&
 		test_cmp expect actual
@@ -115,12 +106,12 @@ test_expect_success '-z uses nul-terminated format' '
 
 test_expect_success 'git repo info uses the last requested format' '
 	echo "layout.bare=false" >expected &&
-	git repo info --format=nul -z --format=keyvalue layout.bare >actual &&
+	git repo info --format=nul -z --format=lines layout.bare >actual &&
 	test_cmp expected actual
 '
 
-test_expect_success 'git repo info --all returns all key-value pairs' '
-	git repo info $REPO_INFO_KEYS >expect &&
+test_expect_success 'git repo info --all and git repo info $(git repo info --keys) output the same data' '
+	git repo info $(git repo info --keys) >expect &&
 	git repo info --all >actual &&
 	test_cmp expect actual
 '
@@ -131,4 +122,31 @@ test_expect_success 'git repo info --all <key> aborts' '
 	test_cmp expect actual
 '
 
+test_expect_success 'git repo info --keys --format=nul uses nul-terminated output' '
+	git repo info --keys --format=lines >lines &&
+	lf_to_nul <lines >expect &&
+	git repo info --keys --format=nul >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'git repo info --keys aborts when using --format other than lines or nul' '
+	echo "fatal: --keys can only be used with --format=lines or --format=nul" >expect &&
+	test_must_fail git repo info --keys --format=table 2>actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'git repo info --keys aborts when requesting keys' '
+	echo "fatal: --keys cannot be used with a <key> or --all" >expect &&
+	test_must_fail git repo info --keys --all 2>actual_all &&
+	test_must_fail git repo info --keys some.key 2>actual_key &&
+	test_cmp expect actual_all &&
+	test_cmp expect actual_key
+'
+
+test_expect_success 'git repo info --keys uses lines as its default output format' '
+	git repo info --keys --format=lines >expect &&
+	git repo info --keys >actual &&
+	test_cmp expect actual
+'
+
 test_done

t/t1901-repo-structure.sh

@@ -113,7 +113,7 @@ test_expect_success SHA1 'repository with references and objects' '
 	)
 '
 
-test_expect_success SHA1 'keyvalue and nul format' '
+test_expect_success SHA1 'lines and nul format' '
 	test_when_finished "rm -rf repo" &&
 	git init repo &&
 	(
@@ -140,7 +140,7 @@ test_expect_success SHA1 'keyvalue and nul format' '
 		objects.tags.disk_size=$(object_type_disk_usage tag)
 		EOF
 
-		git repo structure --format=keyvalue >out 2>err &&
+		git repo structure --format=lines >out 2>err &&
 
 		test_cmp expect out &&
 		test_line_count = 0 err &&