Subject: [PATCH v5 13/15] scalar: implement the `delete` command

From: "Matthew John Cheetham via GitGitGadget" <[email-masked]>
Date: Thu, 07 Oct 2021 10:59:07 +0000

From: Matthew John Cheetham <[email-masked]>

Delete an enlistment by first unregistering the repository and then
deleting the enlistment directory (usually the directory containing the
worktree `src/` directory).

On Windows, if the current directory is inside the enlistment's
directory, change to the parent of the enlistment directory, to allow us
to delete the enlistment (directories used by processes e.g. as current
working directories cannot be deleted on Windows).

Co-authored-by: Victoria Dye <[email-masked]>
Signed-off-by: Matthew John Cheetham <[email-masked]>
Signed-off-by: Johannes Schindelin <[email-masked]>
---
 contrib/scalar/scalar.c          | 63 ++++++++++++++++++++++++++++++++
 contrib/scalar/scalar.txt        |  8 ++++
 contrib/scalar/t/t9099-scalar.sh |  9 +++++
 3 files changed, 80 insertions(+)

diff --git a/contrib/scalar/scalar.c b/contrib/scalar/scalar.c
index 234a7dce479..8aaeca7cc64 100644
--- a/contrib/scalar/scalar.c
+++ b/contrib/scalar/scalar.c
@@ -8,6 +8,8 @@
 #include "config.h"
 #include "run-command.h"
 #include "refs.h"
+#include "dir.h"
+#include "packfile.h"
 
 /*
  * Remove the deepest subdirectory in the provided path string. Path must not
@@ -327,6 +329,33 @@ static char *remote_default_branch(const char *url)
 	return NULL;
 }
 
+static int delete_enlistment(struct strbuf *enlistment)
+{
+#ifdef WIN32
+	struct strbuf parent = STRBUF_INIT;
+#endif
+
+	if (unregister_dir())
+		die(_("failed to unregister repository"));
+
+#ifdef WIN32
+	/*
+	 * Change the current directory to one outside of the enlistment so
+	 * that we may delete everything underneath it.
+	 */
+	strbuf_addbuf(&parent, enlistment);
+	strbuf_parent_directory(&parent);
+	if (chdir(parent.buf) < 0)
+		die_errno(_("could not switch to '%s'"), parent.buf);
+	strbuf_release(&parent);
+#endif
+
+	if (remove_dir_recursively(enlistment, 0))
+		die(_("failed to delete enlistment directory"));
+
+	return 0;
+}
+
 static int cmd_clone(int argc, const char **argv)
 {
 	const char *branch = NULL;
@@ -687,6 +716,39 @@ static int cmd_unregister(int argc, const char **argv)
 	return unregister_dir();
 }
 
+static int cmd_delete(int argc, const char **argv)
+{
+	char *cwd = xgetcwd();
+	struct option options[] = {
+		OPT_END(),
+	};
+	const char * const usage[] = {
+		N_("scalar delete <enlistment>"),
+		NULL
+	};
+	struct strbuf enlistment = STRBUF_INIT;
+	int res = 0;
+
+	argc = parse_options(argc, argv, NULL, options,
+			     usage, 0);
+
+	if (argc != 1)
+		usage_with_options(usage, options);
+
+	setup_enlistment_directory(argc, argv, usage, options, &enlistment);
+
+	if (dir_inside_of(cwd, enlistment.buf) >= 0)
+		res = error(_("refusing to delete current working directory"));
+	else {
+		close_object_store(the_repository->objects);
+		res = delete_enlistment(&enlistment);
+	}
+	strbuf_release(&enlistment);
+	free(cwd);
+
+	return res;
+}
+
 static struct {
 	const char *name;
 	int (*fn)(int, const char **);
@@ -697,6 +759,7 @@ static struct {
 	{ "unregister", cmd_unregister },
 	{ "run", cmd_run },
 	{ "reconfigure", cmd_reconfigure },
+	{ "delete", cmd_delete },
 	{ NULL, NULL},
 };
 
diff --git a/contrib/scalar/scalar.txt b/contrib/scalar/scalar.txt
index 2fa96fcabc6..6fc57707718 100644
--- a/contrib/scalar/scalar.txt
+++ b/contrib/scalar/scalar.txt
@@ -14,6 +14,7 @@ scalar register [<enlistment>]
 scalar unregister [<enlistment>]
 scalar run ( all | config | commit-graph | fetch | loose-objects | pack-files ) [<enlistment>]
 scalar reconfigure [ --all | <enlistment> ]
+scalar delete <enlistment>
 
 DESCRIPTION
 -----------
@@ -127,6 +128,13 @@ reconfigure the enlistment.
 With the `--all` option, all enlistments currently registered with Scalar
 will be reconfigured. Use this option after each Scalar upgrade.
 
+Delete
+~~~~~~
+
+delete <enlistment>::
+	This subcommand lets you delete an existing Scalar enlistment from your
+	local file system, unregistering the repository.
+
 SEE ALSO
 --------
 linkgit:git-clone[1], linkgit:git-maintenance[1].
diff --git a/contrib/scalar/t/t9099-scalar.sh b/contrib/scalar/t/t9099-scalar.sh
index 5fe7fabd0e5..7e8771d0eff 100755
--- a/contrib/scalar/t/t9099-scalar.sh
+++ b/contrib/scalar/t/t9099-scalar.sh
@@ -76,4 +76,13 @@ test_expect_success 'scalar reconfigure' '
 	test true = "$(git -C one/src config core.preloadIndex)"
 '
 
+test_expect_success 'scalar delete without enlistment shows a usage' '
+	test_expect_code 129 scalar delete
+'
+
+test_expect_success 'scalar delete with enlistment' '
+	scalar delete cloned &&
+	test_path_is_missing cloned
+'
+
 test_done
-- 
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