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

[dexonsmith]

Summary

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.

[dexonsmith]

Fix unit test; noticed by inspection that the call to TempLink's constructor wasn't using D.path(), so this was dropping a symlink wherever the CWD of the test was.

[dblaikie]

Sounds good :)

[dexonsmith]

In D120691#3352518, @dblaikie wrote:

Sounds good :)

Thanks! Pushed as 15ab7bc3af3c9f38b3404599d76e4ec3727a0f76 after:

• fixing clang-format
• looking at failing bots for Linux (lots of failing tests that look related to OpenMP, so I've ignored...)

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

if (EC || OS.error())
       Path.clear();
   }
   ~TempFile() {
     if (!Path.empty()) {
       EXPECT_FALSE(llvm::sys::fs::remove(Path.str()));
     }
   }
 
+  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; }
 };
 
 } // namespace unittest
 } // namespace llvm
 
 #endif

llvm/unittests/CMakeLists.txt

 add_subdirectory(ObjectYAML)
 add_subdirectory(Option)
 add_subdirectory(Remarks)
 add_subdirectory(Passes)
 add_subdirectory(ProfileData)
 add_subdirectory(Support)
 add_subdirectory(TableGen)
 add_subdirectory(Target)
+add_subdirectory(Testing)
 add_subdirectory(TextAPI)
 add_subdirectory(Transforms)
 add_subdirectory(XRay)
 add_subdirectory(tools)

llvm/unittests/Testing/CMakeLists.txt

+add_subdirectory(Support)

llvm/unittests/Testing/Support/CMakeLists.txt

+set(LLVM_LINK_COMPONENTS
+  Support
+  TestingSupport
+  )
+
+add_llvm_unittest(TestingSupportTests
+  TempPathTest.cpp
+  )
+
+target_link_libraries(TestingSupportTests PRIVATE LLVMTestingSupport)

llvm/unittests/Testing/Support/TempPathTest.cpp

+//===- 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