[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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305395 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 76 insertions, 0 deletions

diff --git a/lib/Testing/CMakeLists.txt b/lib/Testing/CMakeLists.txt
new file mode 100644
index 00000000000..fc23e64eeb7
--- /dev/null
+++ b/lib/Testing/CMakeLists.txt
@@ -0,0 +1 @@
+add_subdirectory(Support)
diff --git a/lib/Testing/LLVMBuild.txt b/lib/Testing/LLVMBuild.txt
new file mode 100644
index 00000000000..cdf83736298
--- /dev/null
+++ b/lib/Testing/LLVMBuild.txt
@@ -0,0 +1,19 @@
+;===- ./lib/Testing/LLVMBuild.txt ------------------------------*- Conf -*--===;
+;
+;                     The LLVM Compiler Infrastructure
+;
+; This file is distributed under the University of Illinois Open Source
+; License. See LICENSE.TXT for details.
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[common]
+subdirectories = Support
diff --git a/lib/Testing/Support/CMakeLists.txt b/lib/Testing/Support/CMakeLists.txt
new file mode 100644
index 00000000000..fa8dfe59c8b
--- /dev/null
+++ b/lib/Testing/Support/CMakeLists.txt
@@ -0,0 +1,12 @@
+add_llvm_library(LLVMTestingSupport
+  Error.cpp
+
+  BUILDTREE_ONLY
+  
+  ADDITIONAL_HEADER_DIRS
+  ${LLVM_MAIN_INCLUDE_DIR}/llvm/Testing/Support
+  )
+
+include_directories(${LLVM_MAIN_SRC_DIR}/utils/unittest/googletest/include)
+include_directories(${LLVM_MAIN_SRC_DIR}/utils/unittest/googlemock/include)
+target_link_libraries(LLVMTestingSupport PRIVATE gtest)
\ No newline at end of file
diff --git a/lib/Testing/Support/Error.cpp b/lib/Testing/Support/Error.cpp
new file mode 100644
index 00000000000..ce0da44da40
--- /dev/null
+++ b/lib/Testing/Support/Error.cpp
@@ -0,0 +1,22 @@
+//===- llvm/Testing/Support/Error.cpp -------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Testing/Support/Error.h"
+
+#include "llvm/ADT/StringRef.h"
+
+using namespace llvm;
+
+llvm::detail::ErrorHolder llvm::detail::TakeError(llvm::Error Err) {
+  bool Succeeded = !static_cast<bool>(Err);
+  std::string Message;
+  if (!Succeeded)
+    Message = toString(std::move(Err));
+  return {Succeeded, Message};
+}
diff --git a/lib/Testing/Support/LLVMBuild.txt b/lib/Testing/Support/LLVMBuild.txt
new file mode 100644
index 00000000000..40853e8172d
--- /dev/null
+++ b/lib/Testing/Support/LLVMBuild.txt
@@ -0,0 +1,22 @@
+;===- ./Testing/Support/LLVMBuild.txt --------------------------*- Conf -*--===;
+;
+;                     The LLVM Compiler Infrastructure
+;
+; This file is distributed under the University of Illinois Open Source
+; License. See LICENSE.TXT for details.
+;
+;===------------------------------------------------------------------------===;
+;
+; This is an LLVMBuild description file for the components in this subdirectory.
+;
+; For more information on the LLVMBuild system, please see:
+;
+;   http://llvm.org/docs/LLVMBuild.html
+;
+;===------------------------------------------------------------------------===;
+
+[component_0]
+type = Library
+name = TestingSupport
+parent = Libraries
+required_libraries = Support