clang/unittests/AST/ExternalASTSourceTest.cpp

   1 //===- unittest/AST/ExternalASTSourceTest.cpp -----------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains tests for Clang's ExternalASTSource.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "clang/AST/ExternalASTSource.h"
  14 #include "clang/AST/ASTConsumer.h"
  15 #include "clang/AST/ASTContext.h"
  16 #include "clang/Frontend/CompilerInstance.h"
  17 #include "clang/Frontend/CompilerInvocation.h"
  18 #include "clang/Frontend/FrontendActions.h"
  19 #include "clang/Lex/PreprocessorOptions.h"
  20 #include "llvm/Support/VirtualFileSystem.h"
  21 #include "gtest/gtest.h"
  22
  23 using namespace clang;
  24 using namespace llvm;
  25
  26
  27 class TestFrontendAction : public ASTFrontendAction {
  28 public:
  29   TestFrontendAction(ExternalASTSource *Source) : Source(Source) {}
  30
  31 private:
  32   void ExecuteAction() override {
  33     getCompilerInstance().getASTContext().setExternalSource(Source);
  34     getCompilerInstance().getASTContext().getTranslationUnitDecl()
  35         ->setHasExternalVisibleStorage();
  36     return ASTFrontendAction::ExecuteAction();
  37   }
  38
  39   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
  40                                                  StringRef InFile) override {
  41     return std::make_unique<ASTConsumer>();
  42   }
  43
  44   IntrusiveRefCntPtr<ExternalASTSource> Source;
  45 };
  46
  47 bool testExternalASTSource(ExternalASTSource *Source,
  48                            StringRef FileContents) {
  49   CompilerInstance Compiler;
  50   Compiler.createDiagnostics(*llvm::vfs::getRealFileSystem());
  51
  52   auto Invocation = std::make_shared<CompilerInvocation>();
  53   Invocation->getPreprocessorOpts().addRemappedFile(
  54       "test.cc", MemoryBuffer::getMemBuffer(FileContents).release());
  55   const char *Args[] = { "test.cc" };
  56   CompilerInvocation::CreateFromArgs(*Invocation, Args,
  57                                      Compiler.getDiagnostics());
  58   Compiler.setInvocation(std::move(Invocation));
  59
  60   TestFrontendAction Action(Source);
  61   return Compiler.ExecuteAction(Action);
  62 }
  63
  64
  65 // Ensure that a failed name lookup into an external source only occurs once.
  66 TEST(ExternalASTSourceTest, FailedLookupOccursOnce) {
  67   struct TestSource : ExternalASTSource {
  68     TestSource(unsigned &Calls) : Calls(Calls) {}
  69
  70     bool FindExternalVisibleDeclsByName(const DeclContext *,
  71                                         DeclarationName Name) override {
  72       if (Name.getAsString() == "j")
  73         ++Calls;
  74       return false;
  75     }
  76
  77     unsigned &Calls;
  78   };
  79
  80   unsigned Calls = 0;
  81   ASSERT_TRUE(testExternalASTSource(new TestSource(Calls), "int j, k = j;"));
  82   EXPECT_EQ(1u, Calls);
  83 }