[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

llvm/include/llvm/Testing/Support/Error.h

@@ -0,0 +1,69 @@
+//===- llvm/Testing/Support/Error.h ---------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TESTING_SUPPORT_ERROR_H
+#define LLVM_TESTING_SUPPORT_ERROR_H
+
+#include "llvm/ADT/Optional.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Testing/Support/SupportHelpers.h"
+
+#include "gmock/gmock.h"
+#include <ostream>
+
+namespace llvm {
+namespace detail {
+ErrorHolder TakeError(Error Err);
+
+template <typename T> ExpectedHolder<T> TakeExpected(Expected<T> &Exp) {
+  llvm::detail::ExpectedHolder<T> Result;
+  auto &EH = static_cast<llvm::detail::ErrorHolder &>(Result);
+  EH = TakeError(Exp.takeError());
+  if (Result.Success)
+    Result.Value = &(*Exp);
+  return Result;
+}
+
+template <typename T> ExpectedHolder<T> TakeExpected(const Expected<T> &Exp) {
+  return TakeExpected(const_cast<Expected<T> &>(Exp));
+}
+} // namespace detail
+
+#define EXPECT_THAT_ERROR(Err, Matcher)                                        \
+  EXPECT_THAT(llvm::detail::TakeError(Err), Matcher)
+#define ASSERT_THAT_ERROR(Err, Matcher)                                        \
+  ASSERT_THAT(llvm::detail::TakeError(Err), Matcher)
+
+#define EXPECT_THAT_EXPECTED(Err, Matcher)                                     \
+  EXPECT_THAT(llvm::detail::TakeExpected(Err), Matcher)
+#define ASSERT_THAT_EXPECTED(Err, Matcher)                                     \
+  ASSERT_THAT(llvm::detail::TakeExpected(Err), Matcher)
+
+MATCHER(Succeeded, "") { return arg.Success; }
+MATCHER(Failed, "") { return !arg.Success; }
+
+MATCHER_P(HasValue, value,
+          "succeeded with value " + testing::PrintToString(value)) {
+  if (!arg.Success) {
+    *result_listener << "operation failed";
+    return false;
+  }
+
+  assert(arg.Value.hasValue());
+  if (**arg.Value != value) {
+    *result_listener << "but \"" + testing::PrintToString(**arg.Value) +
+                            "\" != " + testing::PrintToString(value);
+    return false;
+  }
+
+  return true;
+}
+} // namespace llvm
+
+#endif

llvm/include/llvm/Testing/Support/SupportHelpers.h

@@ -0,0 +1,46 @@
+//===- Testing/Support/SupportHelpers.h -----------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TESTING_SUPPORT_SUPPORTHELPERS_H
+#define LLVM_TESTING_SUPPORT_SUPPORTHELPERS_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
+
+namespace llvm {
+namespace detail {
+struct ErrorHolder {
+  bool Success;
+  std::string Message;
+};
+
+template <typename T> struct ExpectedHolder : public ErrorHolder {
+  Optional<T *> Value;
+};
+
+inline void PrintTo(const ErrorHolder &Err, std::ostream *Out) {
+  *Out << (Err.Success ? "succeeded" : "failed");
+  if (!Err.Success) {
+    *Out << "  (" << StringRef(Err.Message).trim().str() << ")";
+  }
+}
+
+template <typename T>
+void PrintTo(const ExpectedHolder<T> &Item, std::ostream *Out) {
+  if (Item.Success) {
+    *Out << "succeeded with value \"" << testing::PrintToString(**Item.Value)
+         << "\"";
+  } else {
+    PrintTo(static_cast<const ErrorHolder &>(Item), Out);
+  }
+}
+} // namespace detail
+} // namespace llvm
+
+#endif

llvm/lib/CMakeLists.txt

@@ -24,3 +24,4 @@ add_subdirectory(Fuzzer)
 add_subdirectory(Passes)
 add_subdirectory(ToolDrivers)
 add_subdirectory(XRay)
+add_subdirectory(Testing)

llvm/lib/LLVMBuild.txt

@@ -39,6 +39,7 @@ subdirectories =
  Support
  TableGen
  Target
+ Testing
  ToolDrivers
  Transforms
 

llvm/lib/Testing/CMakeLists.txt

@@ -0,0 +1 @@
+add_subdirectory(Support)

llvm/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

llvm/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)

llvm/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};
+}

llvm/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

llvm/unittests/DebugInfo/CodeView/CMakeLists.txt

@@ -1,12 +1,13 @@
-set(LLVM_LINK_COMPONENTS
-  DebugInfoCodeView
-  )
-
-set(DebugInfoCodeViewSources
-  RandomAccessVisitorTest.cpp
-  TypeIndexDiscoveryTest.cpp
-  )
-
-add_llvm_unittest(DebugInfoCodeViewTests
-  ${DebugInfoCodeViewSources}
-  )
+set(LLVM_LINK_COMPONENTS
+  DebugInfoCodeView
+  TestingSupport
+  )
+
+set(DebugInfoCodeViewSources
+  RandomAccessVisitorTest.cpp
+  TypeIndexDiscoveryTest.cpp
+  )
+
+add_llvm_unittest(DebugInfoCodeViewTests
+  ${DebugInfoCodeViewSources}
+  )

llvm/unittests/DebugInfo/CodeView/RandomAccessVisitorTest.cpp

@@ -7,8 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "ErrorChecking.h"
-
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
 #include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
@@ -22,6 +20,7 @@
 #include "llvm/Support/Allocator.h"
 #include "llvm/Support/BinaryItemStream.h"
 #include "llvm/Support/Error.h"
+#include "llvm/Testing/Support/Error.h"
 
 #include "gtest/gtest.h"
 
@@ -219,7 +218,8 @@ TEST_F(RandomAccessVisitorTest, MultipleVisits) {
   for (uint32_t I : IndicesToVisit) {
     TypeIndex TI = TypeIndex::fromArrayIndex(I);
     CVType T = Types.getType(TI);
-    EXPECT_NO_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks));
+    EXPECT_THAT_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks),
+                      Succeeded());
   }
 
   // [0,8) should be present
@@ -247,7 +247,8 @@ TEST_F(RandomAccessVisitorTest, DescendingWithinChunk) {
   for (uint32_t I : IndicesToVisit) {
     TypeIndex TI = TypeIndex::fromArrayIndex(I);
     CVType T = Types.getType(TI);
-    EXPECT_NO_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks));
+    EXPECT_THAT_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks),
+                      Succeeded());
   }
 
   // [0, 7]
@@ -275,7 +276,8 @@ TEST_F(RandomAccessVisitorTest, AscendingWithinChunk) {
   for (uint32_t I : IndicesToVisit) {
     TypeIndex TI = TypeIndex::fromArrayIndex(I);
     CVType T = Types.getType(TI);
-    EXPECT_NO_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks));
+    EXPECT_THAT_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks),
+                      Succeeded());
   }
 
   // [0, 7]
@@ -305,7 +307,8 @@ TEST_F(RandomAccessVisitorTest, StopPrematurelyInChunk) {
   for (uint32_t I : IndicesToVisit) {
     TypeIndex TI = TypeIndex::fromArrayIndex(I);
     CVType T = Types.getType(TI);
-    EXPECT_NO_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks));
+    EXPECT_THAT_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks),
+                      Succeeded());
   }
 
   // [0, 8) should be visited.
@@ -334,7 +337,8 @@ TEST_F(RandomAccessVisitorTest, InnerChunk) {
   for (uint32_t I : IndicesToVisit) {
     TypeIndex TI = TypeIndex::fromArrayIndex(I);
     CVType T = Types.getType(TI);
-    EXPECT_NO_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks));
+    EXPECT_THAT_ERROR(codeview::visitTypeRecord(T, TI, TestState->Callbacks),
+                      Succeeded());
   }
 
   // [4, 9)

llvm/unittests/DebugInfo/CodeView/TypeIndexDiscoveryTest.cpp

@@ -9,7 +9,6 @@
 
 #include "llvm/DebugInfo/CodeView/TypeIndexDiscovery.h"
 
-#include "ErrorChecking.h"
 #include "llvm/DebugInfo/CodeView/TypeTableBuilder.h"
 #include "llvm/Support/Allocator.h"
 

llvm/unittests/DebugInfo/PDB/CMakeLists.txt

@@ -2,6 +2,7 @@ set(LLVM_LINK_COMPONENTS
   DebugInfoCodeView
   DebugInfoMSF
   DebugInfoPDB
+  TestingSupport
   )
 
 set(DebugInfoPDBSources