add: skip tracked paths outside sparse-checkout cone

When 'git add' adds a tracked file that is outside of the
sparse-checkout cone, it checks the SKIP_WORKTREE bit to see if the file
exists outside of the sparse-checkout cone. This is usually correct,
except in the case of a merge conflict outside of the cone.

Modify add_pathspec_matched_against_index() to be more careful about
paths by checking the sparse-checkout patterns in addition to the
SKIP_WORKTREE bit. This causes 'git add' to no longer allow files
outside of the cone that removed the SKIP_WORKTREE bit due to a merge
conflict.

With only this change, users will only be able to add the file after
adding the file to the sparse-checkout cone. A later change will allow
users to force adding even though the file is outside of the
sparse-checkout cone.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/t/t3705-add-sparse-checkout.sh b/t/t3705-add-sparse-checkout.sh
index b2d7986..be6809e 100755
--- a/t/t3705-add-sparse-checkout.sh
+++ b/t/t3705-add-sparse-checkout.sh
@@ -158,6 +158,18 @@ test_expect_success 'do not warn when pathspec matches dense entries' '
 	git ls-files --error-unmatch dense_entry
 '
 
+test_expect_success 'git add fails outside of sparse-checkout definition' '
+	test_when_finished git sparse-checkout disable &&
+	test_commit a &&
+	git sparse-checkout init &&
+	git sparse-checkout set a &&
+	echo >>sparse_entry &&
+
+	git update-index --no-skip-worktree sparse_entry &&
+	test_must_fail git add sparse_entry &&
+	test_sparse_entry_unstaged
+'
+
 test_expect_success 'add obeys advice.updateSparsePath' '
 	setup_sparse_entry &&
 	test_must_fail git -c advice.updateSparsePath=false add sparse_entry 2>stderr &&