[WORK-IN-PROGRESS] Introduce the path walk API into Git for Windows

.gitignore

@@ -165,6 +165,7 @@
 /git-submodule
 /git-submodule--helper
 /git-subtree
+/git-survey
 /git-svn
 /git-switch
 /git-symbolic-ref

Documentation/git-survey.txt

@@ -0,0 +1,36 @@
+git-survey(1)
+=============
+
+NAME
+----
+git-survey - EXPERIMENTAL: Measure various repository dimensions of scale
+
+SYNOPSIS
+--------
+[verse]
+(EXPERIMENTAL!) `git survey` <options>
+
+DESCRIPTION
+-----------
+
+Survey the repository and measure various dimensions of scale.
+
+As repositories grow to "monorepo" size, certain data shapes can cause
+performance problems.  `git-survey` attempts to measure and report on
+known problem areas.
+
+OPTIONS
+-------
+
+--progress::
+	Show progress.  This is automatically enabled when interactive.
+
+OUTPUT
+------
+
+By default, `git survey` will print information about the repository in a
+human-readable format that includes overviews and tables.
+
+GIT
+---
+Part of the linkgit:git[1] suite

Makefile

@@ -1310,6 +1310,7 @@ BUILTIN_OBJS += builtin/sparse-checkout.o
 BUILTIN_OBJS += builtin/stash.o
 BUILTIN_OBJS += builtin/stripspace.o
 BUILTIN_OBJS += builtin/submodule--helper.o
+BUILTIN_OBJS += builtin/survey.o
 BUILTIN_OBJS += builtin/symbolic-ref.o
 BUILTIN_OBJS += builtin/tag.o
 BUILTIN_OBJS += builtin/unpack-file.o

builtin.h

@@ -239,6 +239,7 @@ int cmd_status(int argc, const char **argv, const char *prefix);
 int cmd_stash(int argc, const char **argv, const char *prefix);
 int cmd_stripspace(int argc, const char **argv, const char *prefix);
 int cmd_submodule__helper(int argc, const char **argv, const char *prefix);
+int cmd_survey(int argc, const char **argv, const char *prefix);
 int cmd_switch(int argc, const char **argv, const char *prefix);
 int cmd_symbolic_ref(int argc, const char **argv, const char *prefix);
 int cmd_tag(int argc, const char **argv, const char *prefix);

builtin/survey.c

@@ -0,0 +1,60 @@
+#include "builtin.h"
+#include "config.h"
+#include "parse-options.h"
+
+static const char * const survey_usage[] = {
+	N_("(EXPERIMENTAL!) git survey <options>"),
+	NULL,
+};
+
+struct survey_opts {
+	int verbose;
+	int show_progress;
+};
+
+static struct survey_opts survey_opts = {
+	.verbose = 0,
+	.show_progress = -1, /* defaults to isatty(2) */
+};
+
+static struct option survey_options[] = {
+	OPT__VERBOSE(&survey_opts.verbose, N_("verbose output")),
+	OPT_BOOL(0, "progress", &survey_opts.show_progress, N_("show progress")),
+	OPT_END(),
+};
+
+static int survey_load_config_cb(const char *var, const char *value,
+				 const struct config_context *ctx, void *pvoid)
+{
+	if (!strcmp(var, "survey.verbose")) {
+		survey_opts.verbose = git_config_bool(var, value);
+		return 0;
+	}
+	if (!strcmp(var, "survey.progress")) {
+		survey_opts.show_progress = git_config_bool(var, value);
+		return 0;
+	}
+
+	return git_default_config(var, value, ctx, pvoid);
+}
+
+static void survey_load_config(void)
+{
+	git_config(survey_load_config_cb, NULL);
+}
+
+int cmd_survey(int argc, const char **argv, const char *prefix)
+{
+	if (argc == 2 && !strcmp(argv[1], "-h"))
+		usage_with_options(survey_usage, survey_options);
+
+	prepare_repo_settings(the_repository);
+	survey_load_config();
+
+	argc = parse_options(argc, argv, prefix, survey_options, survey_usage, 0);
+
+	if (survey_opts.show_progress < 0)
+		survey_opts.show_progress = isatty(2);
+
+	return 0;
+}

command-list.txt

@@ -187,6 +187,7 @@ git-stash                               mainporcelain
 git-status                              mainporcelain           info
 git-stripspace                          purehelpers
 git-submodule                           mainporcelain
+git-survey                              mainporcelain
 git-svn                                 foreignscminterface
 git-switch                              mainporcelain           history
 git-symbolic-ref                        plumbingmanipulators

git.c

@@ -623,6 +623,7 @@ static struct cmd_struct commands[] = {
 	{ "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 	{ "stripspace", cmd_stripspace },
 	{ "submodule--helper", cmd_submodule__helper, RUN_SETUP },
+	{ "survey", cmd_survey, RUN_SETUP },
 	{ "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
 	{ "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 	{ "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },

t/t8100-git-survey.sh

@@ -0,0 +1,18 @@
+#!/bin/sh
+
+test_description='git survey'
+
+GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
+export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
+
+TEST_PASSES_SANITIZE_LEAK=0
+export TEST_PASSES_SANITIZE_LEAK
+
+. ./test-lib.sh
+
+test_expect_success 'git survey -h shows experimental warning' '
+	test_expect_code 129 git survey -h 2>usage &&
+	grep "EXPERIMENTAL!" usage
+'
+
+test_done