Try to unbreak Win build differently after 973519826edb76

Looks like the MS STL wants StringMapKeyIterator::operator*() to be const.
Return the result by copy instead of reference to do that.
Assigning to a hash map key iterator doesn't make sense anyways.

Also reverts 123f811fe5b0b which is now hopefully no longer needed.

Differential Revision: https://reviews.llvm.org/D109167

1 files changed, 15 insertions, 1 deletions

diff --git a/llvm/unittests/ADT/StringMapTest.cpp b/llvm/unittests/ADT/StringMapTest.cpp
index 6a3cca5..f38a604 100644
--- a/llvm/unittests/ADT/StringMapTest.cpp
+++ b/llvm/unittests/ADT/StringMapTest.cpp
@@ -308,7 +308,21 @@ TEST_F(StringMapTest, InsertOrAssignTest) {
   EXPECT_EQ(0, try1.first->second.copy);
 }
 
-TEST_F(StringMapTest, IterMapKeys) {
+TEST_F(StringMapTest, IterMapKeysVector) {
+  StringMap<int> Map;
+  Map["A"] = 1;
+  Map["B"] = 2;
+  Map["C"] = 3;
+  Map["D"] = 3;
+
+  std::vector<StringRef> Keys{Map.keys().begin(), Map.keys().end()};
+  llvm::sort(Keys);
+
+  std::vector<StringRef> Expected{{"A", "B", "C", "D"}};
+  EXPECT_EQ(Expected, Keys);
+}
+
+TEST_F(StringMapTest, IterMapKeysSmallVector) {
   StringMap<int> Map;
   Map["A"] = 1;
   Map["B"] = 2;