xref: /llvm-project/clang/unittests/AST/ExternalASTSourceTest.cpp (revision 263fed7ce9d2c155af44829018673caa67fa4f47)
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
71     FindExternalVisibleDeclsByName(const DeclContext *, DeclarationName Name,
72                                    const DeclContext *OriginalDC) override {
73       if (Name.getAsString() == "j")
74         ++Calls;
75       return false;
76     }
77 
78     unsigned &Calls;
79   };
80 
81   unsigned Calls = 0;
82   ASSERT_TRUE(testExternalASTSource(new TestSource(Calls), "int j, k = j;"));
83   EXPECT_EQ(1u, Calls);
84 }
85