[clang-tools-extra] [clangd] [C++20] [Modules] Introduce initial support for C++20 Modules (PR #66462)

[Chuanqi Xu via cfe-commits]

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+//===--------------- PrerequisiteModulesTests.cpp -------------------*- C++
+//-*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+/// FIXME: Skip testing on windows temporarily due to the different escaping
+/// code mode.
+#ifndef _WIN32
+
+#include "ModulesBuilder.h"
+
+#include "Annotations.h"
+#include "CodeComplete.h"
+#include "Compiler.h"
+#include "TestTU.h"
+#include "support/ThreadsafeFS.h"
+
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace clang::clangd {
+namespace {
+class PrerequisiteModulesTests : public ::testing::Test {
+  protected:
+  void SetUp() override {
+    ASSERT_FALSE(llvm::sys::fs::createUniqueDirectory("modules-test", TestDir));
+  }
+
+  void TearDown() override { llvm::sys::fs::remove_directories(TestDir); }
+
+public:
+  // Add files to the working testing directory and repalce all the
+  // `__DIR__` to TestDir.
+  void addFile(llvm::StringRef Path, llvm::StringRef Contents) {
+    ASSERT_FALSE(llvm::sys::path::is_absolute(Path));
+
+    SmallString<256> AbsPath(TestDir);
+    llvm::sys::path::append(AbsPath, Path);
+
+    ASSERT_FALSE(llvm::sys::fs::create_directories(
+        llvm::sys::path::parent_path(AbsPath)));
+
+    std::error_code EC;
+    llvm::raw_fd_ostream OS(AbsPath, EC);
+    ASSERT_FALSE(EC);
+
+    std::size_t Pos = Contents.find("__DIR__");
+    while (Pos != llvm::StringRef::npos) {
+      OS << Contents.take_front(Pos);
+      OS << TestDir;
+      Contents = Contents.drop_front(Pos + sizeof("__DIR__") - 1);
+      Pos = Contents.find("__DIR__");
+    }
+
+    OS << Contents;
+  }
+
+  // Get the absolute path for file specified by Path under testing working
+  // directory.
+  std::string getFullPath(llvm::StringRef Path) {
+    SmallString<128> Result(TestDir);
+    llvm::sys::path::append(Result, Path);
+    EXPECT_TRUE(llvm::sys::fs::exists(Result.str()));
+    return Result.str().str();
+  }
+
+  std::unique_ptr<GlobalCompilationDatabase> getGlobalCompilationDatabase() {
+    // The compilation flags with modules are much complex so it looks better
+    // to use DirectoryBasedGlobalCompilationDatabase than a mocked compilation
+    // database.
+    DirectoryBasedGlobalCompilationDatabase::Options Opts(TFS);
+    return std::make_unique<DirectoryBasedGlobalCompilationDatabase>(Opts);
+  }
+
+  ParseInputs getInputs(llvm::StringRef FileName,
+                        const GlobalCompilationDatabase &CDB) {
+    std::string FullPathName = getFullPath(FileName);
+
+    ParseInputs Inputs;
+    std::optional<tooling::CompileCommand> Cmd =
+        CDB.getCompileCommand(FullPathName);
+    EXPECT_TRUE(Cmd);
+    Inputs.CompileCommand = std::move(*Cmd);
+    Inputs.TFS = &TFS;
+
+    if (auto Contents = TFS.view(TestDir)->getBufferForFile(FullPathName))
+      Inputs.Contents = Contents->get()->getBuffer().str();
+
+    return Inputs;
+  }
+
+  std::unique_ptr<CompilerInvocation>
+  getCompilerInvocation(const ParseInputs &Inputs) {
+    std::vector<std::string> CC1Args;
+    return buildCompilerInvocation(Inputs, DiagConsumer, &CC1Args);
----------------
ChuanqiXu9 wrote:

Done

https://github.com/llvm/llvm-project/pull/66462