[PATCH v2 5/8] sparse-checkout: add --verbose option to 'clean'

["Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com>]

From: Derrick Stolee <stolee@gmail.com>

The 'git sparse-checkout clean' subcommand is focused on directories,
deleting any tracked sparse directories to clean up the worktree and
make the sparse index feature work optimally.

However, this directory-focused approach can leave users wondering why
those directories exist at all. In my experience, these files are left
over due to ignore or exclude patterns, Windows file handles, or
possibly merge conflict resolutions.

Add a new '--verbose' option for users to see all the files that are
being deleted (with '--force') or would be deleted (with '--dry-run').

Signed-off-by: Derrick Stolee <stolee@gmail.com>
---
 Documentation/git-sparse-checkout.adoc |  5 +++++
 builtin/sparse-checkout.c              | 28 ++++++++++++++++++++++++--
 t/t1091-sparse-checkout-builtin.sh     | 14 ++++++++++---
 3 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/Documentation/git-sparse-checkout.adoc b/Documentation/git-sparse-checkout.adoc
index 823a66c40bc5..604f53f77caf 100644
--- a/Documentation/git-sparse-checkout.adoc
+++ b/Documentation/git-sparse-checkout.adoc
@@ -128,6 +128,11 @@ The `--dry-run` option will list the directories that would be removed
 without deleting them. Running in this mode can be helpful to predict the
 behavior of the clean comand or to determine which kinds of files are left
 in the sparse directories.
++
+The `--verbose` option will list every file within the directories that
+are considered for removal. This option is helpful to determine if those
+files are actually important or perhaps to explain why the directory is
+still present despite the current sparse-checkout.
 
 'disable'::
 	Disable the `core.sparseCheckout` config setting, and restore the
diff --git a/builtin/sparse-checkout.c b/builtin/sparse-checkout.c
index fe332ff5f941..f38a0809c098 100644
--- a/builtin/sparse-checkout.c
+++ b/builtin/sparse-checkout.c
@@ -930,6 +930,26 @@ static char const * const builtin_sparse_checkout_clean_usage[] = {
 	NULL
 };
 
+static int list_file_iterator(const char *path, const void *data)
+{
+	const char *msg = data;
+
+	printf(msg, path);
+	return 0;
+}
+
+static void list_every_file_in_dir(const char *msg,
+				   const char *directory)
+{
+	struct strbuf path = STRBUF_INIT;
+
+	strbuf_addstr(&path, directory);
+	fprintf(stderr, "list every file in %s\n", directory);
+
+	for_each_file_in_dir(&path, list_file_iterator, msg);
+	strbuf_release(&path);
+}
+
 static const char *msg_remove = N_("Removing %s\n");
 static const char *msg_would_remove = N_("Would remove %s\n");
 
@@ -940,12 +960,13 @@ static int sparse_checkout_clean(int argc, const char **argv,
 	struct strbuf full_path = STRBUF_INIT;
 	const char *msg = msg_remove;
 	size_t worktree_len;
-	int force = 0, dry_run = 0;
+	int force = 0, dry_run = 0, verbose = 0;
 	int require_force = 1;
 
 	struct option builtin_sparse_checkout_clean_options[] = {
 		OPT__DRY_RUN(&dry_run, N_("dry run")),
 		OPT__FORCE(&force, N_("force"), PARSE_OPT_NOCOMPLETE),
+		OPT__VERBOSE(&verbose, N_("report each affected file, not just directories")),
 		OPT_END(),
 	};
 
@@ -987,7 +1008,10 @@ static int sparse_checkout_clean(int argc, const char **argv,
 		if (!is_directory(full_path.buf))
 			continue;
 
-		printf(msg, ce->name);
+		if (verbose)
+			list_every_file_in_dir(msg, ce->name);
+		else
+			printf(msg, ce->name);
 
 		if (dry_run <= 0 &&
 		    remove_dir_recursively(&full_path, 0))
diff --git a/t/t1091-sparse-checkout-builtin.sh b/t/t1091-sparse-checkout-builtin.sh
index 69f5a6dcc689..9a89b902c3f5 100755
--- a/t/t1091-sparse-checkout-builtin.sh
+++ b/t/t1091-sparse-checkout-builtin.sh
@@ -1052,9 +1052,9 @@ test_expect_success 'check-rules null termination' '
 
 test_expect_success 'clean' '
 	git -C repo sparse-checkout set --cone deep/deeper1 &&
-	mkdir repo/deep/deeper2 repo/folder1 &&
+	mkdir -p repo/deep/deeper2 repo/folder1/extra/inside &&
 	touch repo/deep/deeper2/file &&
-	touch repo/folder1/file &&
+	touch repo/folder1/extra/inside/file &&
 
 	test_must_fail git -C repo sparse-checkout clean 2>err &&
 	grep "refusing to clean" err &&
@@ -1071,7 +1071,15 @@ test_expect_success 'clean' '
 	git -C repo sparse-checkout clean --dry-run >out &&
 	test_cmp expect out &&
 	test_path_exists repo/deep/deeper2 &&
-	test_path_exists repo/folder1 &&
+	test_path_exists repo/folder1/extra/inside/file &&
+
+	cat >expect <<-\EOF &&
+	Would remove deep/deeper2/file
+	Would remove folder1/extra/inside/file
+	EOF
+
+	git -C repo sparse-checkout clean --dry-run --verbose >out &&
+	test_cmp expect out &&
 
 	cat >expect <<-\EOF &&
 	Removing deep/deeper2/
-- 
gitgitgadget