[Support][ErrorOr] Add optimized specialization of ErrorOr<void>.

ErrorOr<void> represents an operation that returns nothing, but can still fail.
It should be used in cases where you need the aditional user data that ErrorOr
provides over error_code.

llvm-svn: 173209

1 files changed, 11 insertions, 0 deletions

diff --git a/llvm/unittests/Support/ErrorOrTest.cpp b/llvm/unittests/Support/ErrorOrTest.cpp
index b30895c..a860886 100644
--- a/llvm/unittests/Support/ErrorOrTest.cpp
+++ b/llvm/unittests/Support/ErrorOrTest.cpp
@@ -45,6 +45,9 @@ TEST(ErrorOr, Types) {
   *a = 42;
   EXPECT_EQ(42, x);
 
+  EXPECT_FALSE(ErrorOr<void>(make_error_code(errc::broken_pipe)));
+  EXPECT_TRUE(ErrorOr<void>(make_error_code(errc::success)));
+
 #if LLVM_HAS_CXX11_STDLIB
   // Move only types.
   EXPECT_EQ(3, **t3());
@@ -71,10 +74,18 @@ ErrorOr<int> t4() {
   return InvalidArgError("adena");
 }
 
+ErrorOr<void> t5() {
+  return InvalidArgError("pie");
+}
+
 namespace {
 TEST(ErrorOr, UserErrorData) {
   ErrorOr<int> a = t4();
   EXPECT_EQ(errc::invalid_argument, a);
   EXPECT_EQ("adena", t4().getError<InvalidArgError>().ArgName);
+  
+  ErrorOr<void> b = t5();
+  EXPECT_EQ(errc::invalid_argument, b);
+  EXPECT_EQ("pie", b.getError<InvalidArgError>().ArgName);
 }
 } // end anon namespace