Testing: Make TempFile safe to move; test Temp{Dir,File,Link}

Default the moves and delete the copies for TempFile, matching TempDir
and TempLink, and add tests for all of them to confirm that the
destructor is not harmful after it has been moved from.

Differential Revision: https://reviews.llvm.org/D120691

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

@@ -238,6 +238,12 @@ public:
     }
   }
 
+  TempFile(const TempFile &) = delete;
+  TempFile &operator=(const TempFile &) = delete;
+
+  TempFile(TempFile &&) = default;
+  TempFile &operator=(TempFile &&) = default;
+
   /// The path to the file.
   StringRef path() const { return Path; }
 };

llvm/unittests/CMakeLists.txt

@@ -45,6 +45,7 @@ add_subdirectory(ProfileData)
 add_subdirectory(Support)
 add_subdirectory(TableGen)
 add_subdirectory(Target)
+add_subdirectory(Testing)
 add_subdirectory(TextAPI)
 add_subdirectory(Transforms)
 add_subdirectory(XRay)

llvm/unittests/Testing/CMakeLists.txt

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

llvm/unittests/Testing/Support/CMakeLists.txt

@@ -0,0 +1,10 @@
+set(LLVM_LINK_COMPONENTS
+  Support
+  TestingSupport
+  )
+
+add_llvm_unittest(TestingSupportTests
+  TempPathTest.cpp
+  )
+
+target_link_libraries(TestingSupportTests PRIVATE LLVMTestingSupport)

llvm/unittests/Testing/Support/TempPathTest.cpp

@@ -0,0 +1,100 @@
+//===- TempPathTest.cpp ---------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Testing/Support/SupportHelpers.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using llvm::unittest::TempDir;
+using llvm::unittest::TempFile;
+using llvm::unittest::TempLink;
+
+namespace {
+
+TEST(TempPathTest, TempDir) {
+  Optional<TempDir> Dir1, Dir2;
+  StringRef Prefix = "temp-path-test";
+  Dir1.emplace(Prefix, /*Unique=*/true);
+  EXPECT_EQ(Prefix,
+            sys::path::filename(Dir1->path()).take_front(Prefix.size()));
+  EXPECT_NE(Prefix, sys::path::filename(Dir1->path()));
+
+  std::string Path = Dir1->path().str();
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  Dir2 = std::move(*Dir1);
+  ASSERT_EQ(Path, Dir2->path());
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  Dir1 = None;
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  Dir2 = None;
+  ASSERT_FALSE(sys::fs::exists(Path));
+}
+
+TEST(TempPathTest, TempFile) {
+  TempDir D("temp-path-test", /*Unique=*/true);
+  ASSERT_TRUE(sys::fs::exists(D.path()));
+
+  Optional<TempFile> File1, File2;
+  File1.emplace(D.path("file"), "suffix", "content");
+  EXPECT_EQ("file.suffix", sys::path::filename(File1->path()));
+  {
+    ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
+        MemoryBuffer::getFile(File1->path());
+    ASSERT_TRUE(Buffer);
+    ASSERT_EQ("content", (*Buffer)->getBuffer());
+  }
+
+  std::string Path = File1->path().str();
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  File2 = std::move(*File1);
+  ASSERT_EQ(Path, File2->path());
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  File1 = None;
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  File2 = None;
+  ASSERT_FALSE(sys::fs::exists(Path));
+}
+
+TEST(TempPathTest, TempLink) {
+  TempDir D("temp-path-test", /*Unique=*/true);
+  ASSERT_TRUE(sys::fs::exists(D.path()));
+  TempFile File(D.path("file"), "suffix", "content");
+
+  Optional<TempLink> Link1, Link2;
+  Link1.emplace(File.path(), D.path("link"));
+  EXPECT_EQ("link", sys::path::filename(Link1->path()));
+  {
+    ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
+        MemoryBuffer::getFile(Link1->path());
+    ASSERT_TRUE(Buffer);
+    ASSERT_EQ("content", (*Buffer)->getBuffer());
+  }
+
+  std::string Path = Link1->path().str();
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  Link2 = std::move(*Link1);
+  ASSERT_EQ(Path, Link2->path());
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  Link1 = None;
+  ASSERT_TRUE(sys::fs::exists(Path));
+
+  Link2 = None;
+  ASSERT_FALSE(sys::fs::exists(Path));
+}
+
+} // namespace