[gtest] Create a shared include directory for gtest utilities.

Many times unit tests for different libraries would like to use
the same helper functions for checking common types of errors.

This patch adds a common library with helpers for testing things
in Support, and introduces helpers in here for integrating the
llvm::Error and llvm::Expected<T> classes with gtest and gmock.

Normally, we would just be able to write:

   EXPECT_THAT(someFunction(), succeeded());

but due to some quirks in llvm::Error's move semantics, gmock
doesn't make this easy, so two macros EXPECT_THAT_ERROR() and
EXPECT_THAT_EXPECTED() are introduced to gloss over the difficulties.
Consider this an exception, and possibly only temporary as we
look for ways to improve this.

Differential Revision: https://reviews.llvm.org/D33059

llvm-svn: 305395

1 files changed, 1 insertions, 0 deletions

diff --git a/llvm/lib/CMakeLists.txt b/llvm/lib/CMakeLists.txt
index f7c09be15fb..946067e6358 100644
--- a/llvm/lib/CMakeLists.txt
+++ b/llvm/lib/CMakeLists.txt
@@ -24,3 +24,4 @@ add_subdirectory(Fuzzer)
 add_subdirectory(Passes)
 add_subdirectory(ToolDrivers)
 add_subdirectory(XRay)
+add_subdirectory(Testing)