Merge branch 'jc/unresolve-removal'

"checkout --merge -- path" and "update-index --unresolve path" did
not resurrect conflicted state that was resolved to remove path,
but now they do.

* jc/unresolve-removal:
  checkout: allow "checkout -m path" to unmerge removed paths
  checkout/restore: add basic tests for --merge
  checkout/restore: refuse unmerging paths unless checking out of the index
  update-index: remove stale fallback code for "--unresolve"
  update-index: use unmerge_index_entry() to support removal
  resolve-undo: allow resurrecting conflicted state that resolved to deletion
  update-index: do not read HEAD and MERGE_HEAD unconditionally

1 files changed, 47 insertions, 0 deletions

diff --git a/t/t7201-co.sh b/t/t7201-co.sh
index 35b9e6ed6b..ebf273e843 100755
--- a/t/t7201-co.sh
+++ b/t/t7201-co.sh
@@ -497,6 +497,11 @@ test_expect_success 'checkout unmerged stage' '
 	test ztheirside = "z$(cat file)"
 '
 
+test_expect_success 'checkout path with --merge from tree-ish is a no-no' '
+	setup_conflicting_index &&
+	test_must_fail git checkout -m HEAD -- file
+'
+
 test_expect_success 'checkout with --merge' '
 	setup_conflicting_index &&
 	echo "none of the above" >sample &&
@@ -517,6 +522,48 @@ test_expect_success 'checkout with --merge' '
 	test_cmp merged file
 '
 
+test_expect_success 'checkout -m works after (mistaken) resolution' '
+	setup_conflicting_index &&
+	echo "none of the above" >sample &&
+	cat sample >fild &&
+	cat sample >file &&
+	cat sample >filf &&
+	# resolve to something
+	git add file &&
+	git checkout --merge -- fild file filf &&
+	{
+		echo "<<<<<<< ours" &&
+		echo ourside &&
+		echo "=======" &&
+		echo theirside &&
+		echo ">>>>>>> theirs"
+	} >merged &&
+	test_cmp expect fild &&
+	test_cmp expect filf &&
+	test_cmp merged file
+'
+
+test_expect_success 'checkout -m works after (mistaken) resolution to remove' '
+	setup_conflicting_index &&
+	echo "none of the above" >sample &&
+	cat sample >fild &&
+	cat sample >file &&
+	cat sample >filf &&
+	# resolve to remove
+	git rm file &&
+	git checkout --merge -- fild file filf &&
+	{
+		echo "<<<<<<< ours" &&
+		echo ourside &&
+		echo "=======" &&
+		echo theirside &&
+		echo ">>>>>>> theirs"
+	} >merged &&
+	test_cmp expect fild &&
+	test_cmp expect filf &&
+	test_cmp merged file
+'
+
 test_expect_success 'checkout with --merge, in diff3 -m style' '
 	git config merge.conflictstyle diff3 &&
 	setup_conflicting_index &&