1 files changed, 152 insertions, 0 deletions
diff --git a/clang/unittests/Tooling/DependencyScanning/DependencyScanningFilesystemTest.cpp b/clang/unittests/Tooling/DependencyScanning/DependencyScanningFilesystemTest.cpp
new file mode 100644
index 0000000..50cad72
--- /dev/null
+++ b/clang/unittests/Tooling/DependencyScanning/DependencyScanningFilesystemTest.cpp
@@ -0,0 +1,152 @@
+//===- DependencyScanningFilesystemTest.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 "clang/Tooling/DependencyScanning/DependencyScanningFilesystem.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Support/VirtualFileSystem.h"
+#include "gtest/gtest.h"
+
+using namespace clang::tooling::dependencies;
+
+namespace {
+struct InstrumentingFilesystem
+    : llvm::RTTIExtends<InstrumentingFilesystem, llvm::vfs::ProxyFileSystem> {
+  unsigned NumStatusCalls = 0;
+  unsigned NumGetRealPathCalls = 0;
+
+  using llvm::RTTIExtends<InstrumentingFilesystem,
+                          llvm::vfs::ProxyFileSystem>::RTTIExtends;
+
+  llvm::ErrorOr<llvm::vfs::Status> status(const llvm::Twine &Path) override {
+    ++NumStatusCalls;
+    return ProxyFileSystem::status(Path);
+  }
+
+  std::error_code getRealPath(const llvm::Twine &Path,
+                              llvm::SmallVectorImpl<char> &Output) override {
+    ++NumGetRealPathCalls;
+    return ProxyFileSystem::getRealPath(Path, Output);
+  }
+};
+} // namespace
+
+TEST(DependencyScanningWorkerFilesystem, CacheStatusFailures) {
+  auto InMemoryFS = llvm::makeIntrusiveRefCnt<llvm::vfs::InMemoryFileSystem>();
+
+  auto InstrumentingFS =
+      llvm::makeIntrusiveRefCnt<InstrumentingFilesystem>(InMemoryFS);
+
+  DependencyScanningFilesystemSharedCache SharedCache;
+  DependencyScanningWorkerFilesystem DepFS(SharedCache, InstrumentingFS);
+  DependencyScanningWorkerFilesystem DepFS2(SharedCache, InstrumentingFS);
+
+  DepFS.status("/foo.c");
+  EXPECT_EQ(InstrumentingFS->NumStatusCalls, 1u);
+
+  DepFS.status("/foo.c");
+  EXPECT_EQ(InstrumentingFS->NumStatusCalls, 1u); // Cached, no increase.
+
+  DepFS.status("/bar.c");
+  EXPECT_EQ(InstrumentingFS->NumStatusCalls, 2u);
+
+  DepFS2.status("/foo.c");
+  EXPECT_EQ(InstrumentingFS->NumStatusCalls, 2u); // Shared cache.
+}
+
+TEST(DependencyScanningFilesystem, CacheGetRealPath) {
+  auto InMemoryFS = llvm::makeIntrusiveRefCnt<llvm::vfs::InMemoryFileSystem>();
+  InMemoryFS->setCurrentWorkingDirectory("/");
+  InMemoryFS->addFile("/foo", 0, llvm::MemoryBuffer::getMemBuffer(""));
+  InMemoryFS->addFile("/bar", 0, llvm::MemoryBuffer::getMemBuffer(""));
+
+  auto InstrumentingFS =
+      llvm::makeIntrusiveRefCnt<InstrumentingFilesystem>(InMemoryFS);
+
+  DependencyScanningFilesystemSharedCache SharedCache;
+  DependencyScanningWorkerFilesystem DepFS(SharedCache, InstrumentingFS);
+  DependencyScanningWorkerFilesystem DepFS2(SharedCache, InstrumentingFS);
+
+  {
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/foo", Result);
+    EXPECT_EQ(InstrumentingFS->NumGetRealPathCalls, 1u);
+  }
+
+  {
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/foo", Result);
+    EXPECT_EQ(InstrumentingFS->NumGetRealPathCalls, 1u); // Cached, no increase.
+  }
+
+  {
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/bar", Result);
+    EXPECT_EQ(InstrumentingFS->NumGetRealPathCalls, 2u);
+  }
+
+  {
+    llvm::SmallString<128> Result;
+    DepFS2.getRealPath("/foo", Result);
+    EXPECT_EQ(InstrumentingFS->NumGetRealPathCalls, 2u); // Shared cache.
+  }
+}
+
+TEST(DependencyScanningFilesystem, RealPathAndStatusInvariants) {
+  auto InMemoryFS = llvm::makeIntrusiveRefCnt<llvm::vfs::InMemoryFileSystem>();
+  InMemoryFS->setCurrentWorkingDirectory("/");
+  InMemoryFS->addFile("/foo.c", 0, llvm::MemoryBuffer::getMemBuffer(""));
+  InMemoryFS->addFile("/bar.c", 0, llvm::MemoryBuffer::getMemBuffer(""));
+
+  auto InstrumentingFS =
+      llvm::makeIntrusiveRefCnt<InstrumentingFilesystem>(InMemoryFS);
+
+  DependencyScanningFilesystemSharedCache SharedCache;
+  DependencyScanningWorkerFilesystem DepFS(SharedCache, InstrumentingFS);
+
+  // Success.
+  {
+    DepFS.status("/foo.c");
+
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/foo.c", Result);
+  }
+  {
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/bar.c", Result);
+
+    DepFS.status("/bar.c");
+  }
+
+  // Failure.
+  {
+    DepFS.status("/foo.m");
+
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/foo.m", Result);
+  }
+  {
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/bar.m", Result);
+
+    DepFS.status("/bar.m");
+  }
+
+  // Failure without caching.
+  {
+    DepFS.status("/foo");
+
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/foo", Result);
+  }
+  {
+    llvm::SmallString<128> Result;
+    DepFS.getRealPath("/bar", Result);
+
+    DepFS.status("/bar");
+  }
+}