[PATCH] unpack-trees: don't update files flagged for deletion

[David Turner <dturner@twopensource.com>]

Don't update files in the worktree from cache entries which are
flagged with CE_WT_REMOVE.  This is fixes merges in sparse
checkouts.

Signed-off-by: Anatole Shaw <git-devel@omni.poc.net>
Signed-off-by: David Turner <dturner@twopensource.com>
---

This patch was written by my colleague Anatole Shaw for Twitter's git;
I just rebased it on mainstream git.  Anatole has given me permission
to send this upstream.

---
 t/t1090-sparse-checkout-scope.sh | 52 ++++++++++++++++++++++++++++++++++++++++
 unpack-trees.c                   |  2 +-
 2 files changed, 53 insertions(+), 1 deletion(-)
 create mode 100755 t/t1090-sparse-checkout-scope.sh

diff --git a/t/t1090-sparse-checkout-scope.sh b/t/t1090-sparse-checkout-scope.sh
new file mode 100755
index 0000000..1f61eb3
--- /dev/null
+++ b/t/t1090-sparse-checkout-scope.sh
@@ -0,0 +1,52 @@
+#!/bin/sh
+
+test_description='sparse checkout scope tests'
+
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	echo "initial" >a &&
+	echo "initial" >b &&
+	echo "initial" >c &&
+	git add a b c &&
+	git commit -m "initial commit"
+'
+
+test_expect_success 'create feature branch' '
+	git checkout -b feature &&
+	echo "modified" >b &&
+	echo "modified" >c &&
+	git add b c &&
+	git commit -m "modification"
+'
+
+test_expect_success 'perform sparse checkout of master' '
+	git config --local --bool core.sparsecheckout true &&
+	echo "!/*" >.git/info/sparse-checkout &&
+	echo "/a" >>.git/info/sparse-checkout &&
+	echo "/c" >>.git/info/sparse-checkout &&
+	git checkout master &&
+	test_path_is_file a &&
+	test_path_is_missing b &&
+	test_path_is_file c
+'
+
+test_expect_success 'merge feature branch into sparse checkout of master' '
+	git merge feature &&
+	test_path_is_file a &&
+	test_path_is_missing b &&
+	test_path_is_file c &&
+	test "$(cat c)" = "modified"
+'
+
+test_expect_success 'return to full checkout of master' '
+	git checkout feature &&
+	echo "/*" >.git/info/sparse-checkout &&
+	git checkout master &&
+	test_path_is_file a &&
+	test_path_is_file b &&
+	test_path_is_file c &&
+	test "$(cat b)" = "modified"
+'
+
+test_done
diff --git a/unpack-trees.c b/unpack-trees.c
index 2927660..11a5300 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -223,7 +223,7 @@ static int check_updates(struct unpack_trees_options *o)
 	for (i = 0; i < index->cache_nr; i++) {
 		struct cache_entry *ce = index->cache[i];
 
-		if (ce->ce_flags & CE_UPDATE) {
+		if (ce->ce_flags & CE_UPDATE && !(ce->ce_flags & CE_WT_REMOVE)) {
 			display_progress(progress, ++cnt);
 			ce->ce_flags &= ~CE_UPDATE;
 			if (o->update && !o->dry_run) {
-- 
2.0.4.315.gad8727a-twtrsrc