ADT: Add some missing coverage for iplist::splice
These splices are interesting because they involve swapping two nodes in
the same list. There are two ways to do this. Assuming:
A -> B -> [Sentinel]
You can either:
- splice B before A, with: L.splice(A, L, B) or
- splice A before Sentinel, with: L.splice(L.end(), L, A) to create:
B -> A -> [Sentinel]
These two swapping-splices are somewhat interesting corner cases for
maintaining the list invariants. The tests pass even with my new ilist
implementation, but I had some doubts about the latter when I was
looking at weird UB effects. Since I can't find equivalent explicit
test coverage elsewhere it seems prudent to commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278887 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/ADT/ilistTest.cpp b/unittests/ADT/ilistTest.cpp
index 377dcc0..b63cfd6 100644
--- a/unittests/ADT/ilistTest.cpp
+++ b/unittests/ADT/ilistTest.cpp
@@ -64,6 +64,38 @@
EXPECT_EQ(3, List.back().Value);
}
+TEST(ilistTest, SpliceSwap) {
+ ilist<Node> L;
+ Node N0(0);
+ Node N1(1);
+ L.insert(L.end(), &N0);
+ L.insert(L.end(), &N1);
+ EXPECT_EQ(0, L.front().Value);
+ EXPECT_EQ(1, L.back().Value);
+
+ L.splice(L.begin(), L, ++L.begin());
+ EXPECT_EQ(1, L.front().Value);
+ EXPECT_EQ(0, L.back().Value);
+
+ L.clearAndLeakNodesUnsafely();
+}
+
+TEST(ilistTest, SpliceSwapOtherWay) {
+ ilist<Node> L;
+ Node N0(0);
+ Node N1(1);
+ L.insert(L.end(), &N0);
+ L.insert(L.end(), &N1);
+ EXPECT_EQ(0, L.front().Value);
+ EXPECT_EQ(1, L.back().Value);
+
+ L.splice(L.end(), L, L.begin());
+ EXPECT_EQ(1, L.front().Value);
+ EXPECT_EQ(0, L.back().Value);
+
+ L.clearAndLeakNodesUnsafely();
+}
+
TEST(ilistTest, UnsafeClear) {
ilist<Node> List;
