builtin/refs: add list subcommand

Git's reference management is distributed across multiple commands. As
part of an ongoing effort to consolidate and modernize reference
handling, introduce a `list` subcommand under the `git refs` umbrella as
a replacement for `git for-each-ref`.

Implement `cmd_refs_list` by having it call the `for_each_ref_core()`
helper function. This helper was factored out of the original
`cmd_for_each_ref` in a preceding commit, allowing both commands to
share the same core logic as independent peers.

Add documentation for the new command. The man page leverages the shared
options file, created in a previous commit, by using the AsciiDoc
`include::` macro to ensure consistency with git-for-each-ref(1).

Mentored-by: Patrick Steinhardt <ps@pks.im>
Mentored-by: shejialuo <shejialuo@gmail.com>
Mentored-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Meet Soni <meetsoni3017@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: inosmeet

Documentation/git-refs.adoc

@@ -11,6 +11,13 @@ SYNOPSIS
 [synopsis]
 git refs migrate --ref-format=<format> [--no-reflog] [--dry-run]
 git refs verify [--strict] [--verbose]
+git refs list [--count=<count>] [--shell|--perl|--python|--tcl]
+		   [(--sort=<key>)...] [--format=<format>]
+		   [--include-root-refs] [--points-at=<object>]
+		   [--merged[=<object>]] [--no-merged[=<object>]]
+		   [--contains[=<object>]] [--no-contains[=<object>]]
+		   [(--exclude=<pattern>)...] [--start-after=<marker>]
+		   [ --stdin | <pattern>... ]
 
 DESCRIPTION
 -----------
@@ -26,6 +33,11 @@ migrate::
 verify::
 	Verify reference database consistency.
 
+list::
+	List references in the repository with support for filtering,
+	formatting, and sorting. This subcommand is an alias for
+	linkgit:git-for-each-ref[1] and offers identical functionality.
+
 OPTIONS
 -------
 
@@ -57,6 +69,10 @@ The following options are specific to 'git refs verify':
 --verbose::
 	When verifying the reference database consistency, be chatty.
 
+The following options are specific to 'git refs list':
+
+include::for-each-ref-options.adoc[]
+
 KNOWN LIMITATIONS
 -----------------
 

builtin/refs.c

@@ -6,6 +6,7 @@
 #include "refs.h"
 #include "strbuf.h"
 #include "worktree.h"
+#include "for-each-ref.h"
 
 #define REFS_MIGRATE_USAGE \
 	N_("git refs migrate --ref-format=<format> [--no-reflog] [--dry-run]")
@@ -101,6 +102,17 @@ static int cmd_refs_verify(int argc, const char **argv, const char *prefix,
 	return ret;
 }
 
+static int cmd_refs_list(int argc, const char **argv, const char *prefix,
+			   struct repository *repo)
+{
+	static char const * const refs_list_usage[] = {
+		N_("git refs list " COMMON_USAGE_FOR_EACH_REF),
+		NULL
+	};
+
+	return for_each_ref_core(argc, argv, prefix, repo, refs_list_usage);
+}
+
 int cmd_refs(int argc,
 	     const char **argv,
 	     const char *prefix,
@@ -109,12 +121,14 @@ int cmd_refs(int argc,
 	const char * const refs_usage[] = {
 		REFS_MIGRATE_USAGE,
 		REFS_VERIFY_USAGE,
+		"git refs list " COMMON_USAGE_FOR_EACH_REF,
 		NULL,
 	};
 	parse_opt_subcommand_fn *fn = NULL;
 	struct option opts[] = {
 		OPT_SUBCOMMAND("migrate", &fn, cmd_refs_migrate),
 		OPT_SUBCOMMAND("verify", &fn, cmd_refs_verify),
+		OPT_SUBCOMMAND("list", &fn, cmd_refs_list),
 		OPT_END(),
 	};