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/ASTConsumer.h"
  14 #include "clang/AST/ASTContext.h"
  15 #include "clang/AST/ExternalASTSource.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 "gtest/gtest.h"
  21
  22 using namespace clang;
  23 using namespace llvm;
  24
  25
  26 class TestFrontendAction : public ASTFrontendAction {
  27 public:
  28   TestFrontendAction(ExternalASTSource *Source) : Source(Source) {}
  29
  30 private:
  31   void ExecuteAction() override {
  32     getCompilerInstance().getASTContext().setExternalSource(Source);
  33     getCompilerInstance().getASTContext().getTranslationUnitDecl()
  34         ->setHasExternalVisibleStorage();
  35     return ASTFrontendAction::ExecuteAction();
  36   }
  37
  38   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
  39                                                  StringRef InFile) override {
  40     return std::make_unique<ASTConsumer>();
  41   }
  42
  43   IntrusiveRefCntPtr<ExternalASTSource> Source;
  44 };
  45
  46 bool testExternalASTSource(ExternalASTSource *Source,
  47                            StringRef FileContents) {
  48   CompilerInstance Compiler;
  49   Compiler.createDiagnostics();
  50
  51   auto Invocation = std::make_shared<CompilerInvocation>();
  52   Invocation->getPreprocessorOpts().addRemappedFile(
  53       "test.cc", MemoryBuffer::getMemBuffer(FileContents).release());
  54   const char *Args[] = { "test.cc" };
  55   CompilerInvocation::CreateFromArgs(*Invocation, Args,
  56                                      Compiler.getDiagnostics());
  57   Compiler.setInvocation(std::move(Invocation));
  58
  59   TestFrontendAction Action(Source);
  60   return Compiler.ExecuteAction(Action);
  61 }
  62
  63
  64 // Ensure that a failed name lookup into an external source only occurs once.
  65 TEST(ExternalASTSourceTest, FailedLookupOccursOnce) {
  66   struct TestSource : ExternalASTSource {
  67     TestSource(unsigned &Calls) : Calls(Calls) {}
  68
  69     bool FindExternalVisibleDeclsByName(const DeclContext *,
  70                                         DeclarationName Name) override {
  71       if (Name.getAsString() == "j")
  72         ++Calls;
  73       return false;
  74     }
  75
  76     unsigned &Calls;
  77   };
  78
  79   unsigned Calls = 0;
  80   ASSERT_TRUE(testExternalASTSource(new TestSource(Calls), "int j, k = j;"));
  81   EXPECT_EQ(1u, Calls);
  82 }