[PATCH 11/13] mv: refuse to move sparse paths

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

From: Derrick Stolee <dstolee@microsoft.com>

Since cmd_mv() does not operate on cache entries and instead directly
checks the filesystem, we can only use path_in_sparse_checkout() as a
mechanism for seeing if a path is sparse or not. Be sure to skip
returning a failure if '-k' is specified.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
---
 builtin/mv.c                  | 19 +++++++
 t/t7002-mv-sparse-checkout.sh | 99 +++++++++++++++++++++++++++++++++++
 2 files changed, 118 insertions(+)
 create mode 100755 t/t7002-mv-sparse-checkout.sh

diff --git a/builtin/mv.c b/builtin/mv.c
index c2f96c8e895..b58fd4ce5ba 100644
--- a/builtin/mv.c
+++ b/builtin/mv.c
@@ -133,6 +133,7 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
 	struct string_list src_for_dst = STRING_LIST_INIT_NODUP;
 	struct lock_file lock_file = LOCK_INIT;
 	struct cache_entry *ce;
+	struct string_list only_match_skip_worktree = STRING_LIST_INIT_NODUP;
 
 	git_config(git_default_config, NULL);
 
@@ -176,10 +177,22 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
 		const char *src = source[i], *dst = destination[i];
 		int length, src_is_dir;
 		const char *bad = NULL;
+		int skip_sparse = 0;
 
 		if (show_only)
 			printf(_("Checking rename of '%s' to '%s'\n"), src, dst);
 
+		if (!path_in_sparse_checkout(src, &the_index)) {
+			string_list_append(&only_match_skip_worktree, src);
+			skip_sparse = 1;
+		}
+		if (!path_in_sparse_checkout(dst, &the_index)) {
+			string_list_append(&only_match_skip_worktree, dst);
+			skip_sparse = 1;
+		}
+		if (skip_sparse)
+			continue;
+
 		length = strlen(src);
 		if (lstat(src, &st) < 0)
 			bad = _("bad source");
@@ -266,6 +279,12 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
 		}
 	}
 
+	if (only_match_skip_worktree.nr) {
+		advise_on_updating_sparse_paths(&only_match_skip_worktree);
+		if (!ignore_errors)
+			return 1;
+	}
+
 	for (i = 0; i < argc; i++) {
 		const char *src = source[i], *dst = destination[i];
 		enum update_mode mode = modes[i];
diff --git a/t/t7002-mv-sparse-checkout.sh b/t/t7002-mv-sparse-checkout.sh
new file mode 100755
index 00000000000..5397c6d07bd
--- /dev/null
+++ b/t/t7002-mv-sparse-checkout.sh
@@ -0,0 +1,99 @@
+#!/bin/sh
+
+test_description='git mv in sparse working trees'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' "
+	mkdir -p sub/dir sub/dir2 &&
+	touch a b c sub/d sub/dir/e sub/dir2/e &&
+	git add -A &&
+	git commit -m files &&
+
+	cat >sparse_error_header <<-EOF &&
+	The following pathspecs didn't match any eligible path, but they do match index
+	entries outside the current sparse checkout:
+	EOF
+
+	cat >sparse_hint <<-EOF
+	hint: Disable or modify the sparsity rules if you intend to update such entries.
+	hint: Disable this message with \"git config advice.updateSparsePath false\"
+	EOF
+"
+
+test_expect_success 'mv refuses to move sparse-to-sparse' '
+	rm -f e &&
+	git reset --hard &&
+	git sparse-checkout set a &&
+	touch b &&
+	test_must_fail git mv b e 2>stderr &&
+	cat sparse_error_header >expect &&
+	echo b >>expect &&
+	echo e >>expect &&
+	cat sparse_hint >>expect &&
+	test_cmp expect stderr
+'
+
+test_expect_success 'mv refuses to move sparse-to-sparse, ignores failure' '
+	rm -f e &&
+	git reset --hard &&
+	git sparse-checkout set a &&
+	touch b &&
+	git mv -k b e 2>stderr &&
+	cat sparse_error_header >expect &&
+	echo b >>expect &&
+	echo e >>expect &&
+	cat sparse_hint >>expect &&
+	test_cmp expect stderr
+'
+
+test_expect_success 'mv refuses to move non-sparse-to-sparse' '
+	rm -f e &&
+	git reset --hard &&
+	git sparse-checkout set a &&
+	test_must_fail git mv a e 2>stderr &&
+	cat sparse_error_header >expect &&
+	echo e >>expect &&
+	cat sparse_hint >>expect &&
+	test_cmp expect stderr
+'
+
+test_expect_success 'mv refuses to move sparse-to-non-sparse' '
+	rm -f e &&
+	git reset --hard &&
+	git sparse-checkout set a e &&
+	touch b &&
+	test_must_fail git mv b e 2>stderr &&
+	cat sparse_error_header >expect &&
+	echo b >>expect &&
+	cat sparse_hint >>expect &&
+	test_cmp expect stderr
+'
+
+test_expect_success 'recursive mv refuses to move (possible) sparse' '
+	rm -f e &&
+	git reset --hard &&
+	# Without cone mode, "sub" and "sub2" do not match
+	git sparse-checkout set sub/dir sub2/dir &&
+	test_must_fail git mv sub sub2 2>stderr &&
+	cat sparse_error_header >expect &&
+	echo sub >>expect &&
+	echo sub2 >>expect &&
+	cat sparse_hint >>expect &&
+	test_cmp expect stderr
+'
+
+test_expect_success 'recursive mv refuses to move sparse' '
+	git reset --hard &&
+	# Use cone mode so "sub/" matches the sparse-checkout patterns
+	git sparse-checkout init --cone &&
+	git sparse-checkout set sub/dir sub2/dir &&
+	test_must_fail git mv sub sub2 2>stderr &&
+	cat sparse_error_header >expect &&
+	echo sub/dir2/e >>expect &&
+	echo sub2/dir2/e >>expect &&
+	cat sparse_hint >>expect &&
+	test_cmp expect stderr
+'
+
+test_done
-- 
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