clang-tools-extra/include-cleaner/unittests/WalkASTTest.cpp

   1 #include "AnalysisInternal.h"
   2 #include "clang/AST/ASTContext.h"
   3 #include "clang/Basic/FileManager.h"
   4 #include "clang/Frontend/TextDiagnostic.h"
   5 #include "clang/Testing/TestAST.h"
   6 #include "llvm/Support/Error.h"
   7 #include "llvm/Testing/Support/Annotations.h"
   8 #include "gtest/gtest.h"
   9
  10 namespace clang {
  11 namespace include_cleaner {
  12 namespace {
  13
  14 // Specifies a test of which symbols are referenced by a piece of code.
  15 //
  16 // Example:
  17 //   Target:      int ^foo();
  18 //   Referencing: int x = ^foo();
  19 // There must be exactly one referencing location marked.
  20 void testWalk(llvm::StringRef TargetCode, llvm::StringRef ReferencingCode) {
  21   llvm::Annotations Target(TargetCode);
  22   llvm::Annotations Referencing(ReferencingCode);
  23
  24   TestInputs Inputs(Referencing.code());
  25   Inputs.ExtraFiles["target.h"] = Target.code().str();
  26   Inputs.ExtraArgs.push_back("-include");
  27   Inputs.ExtraArgs.push_back("target.h");
  28   TestAST AST(Inputs);
  29   const auto &SM = AST.sourceManager();
  30
  31   // We're only going to record references from the nominated point,
  32   // to the target file.
  33   FileID ReferencingFile = SM.getMainFileID();
  34   SourceLocation ReferencingLoc =
  35       SM.getComposedLoc(ReferencingFile, Referencing.point());
  36   FileID TargetFile = SM.translateFile(
  37       llvm::cantFail(AST.fileManager().getFileRef("target.h")));
  38
  39   // Perform the walk, and capture the offsets of the referenced targets.
  40   std::vector<size_t> ReferencedOffsets;
  41   for (Decl *D : AST.context().getTranslationUnitDecl()->decls()) {
  42     if (ReferencingFile != SM.getDecomposedExpansionLoc(D->getLocation()).first)
  43       continue;
  44     walkAST(*D, [&](SourceLocation Loc, NamedDecl &ND) {
  45       if (SM.getFileLoc(Loc) != ReferencingLoc)
  46         return;
  47       auto NDLoc = SM.getDecomposedLoc(SM.getFileLoc(ND.getLocation()));
  48       if (NDLoc.first != TargetFile)
  49         return;
  50       ReferencedOffsets.push_back(NDLoc.second);
  51     });
  52   }
  53   llvm::sort(ReferencedOffsets);
  54
  55   // Compare results to the expected points.
  56   // For each difference, show the target point in context, like a diagnostic.
  57   std::string DiagBuf;
  58   llvm::raw_string_ostream DiagOS(DiagBuf);
  59   auto *DiagOpts = new DiagnosticOptions();
  60   DiagOpts->ShowLevel = 0;
  61   DiagOpts->ShowNoteIncludeStack = 0;
  62   TextDiagnostic Diag(DiagOS, AST.context().getLangOpts(), DiagOpts);
  63   auto DiagnosePoint = [&](const char *Message, unsigned Offset) {
  64     Diag.emitDiagnostic(
  65         FullSourceLoc(SM.getComposedLoc(TargetFile, Offset), SM),
  66         DiagnosticsEngine::Note, Message, {}, {});
  67   };
  68   for (auto Expected : Target.points())
  69     if (!llvm::is_contained(ReferencedOffsets, Expected))
  70       DiagnosePoint("location not marked used", Expected);
  71   for (auto Actual : ReferencedOffsets)
  72     if (!llvm::is_contained(Target.points(), Actual))
  73       DiagnosePoint("location unexpectedly used", Actual);
  74
  75   // If there were any differences, we print the entire referencing code once.
  76   if (!DiagBuf.empty())
  77     ADD_FAILURE() << DiagBuf << "\nfrom code:\n" << ReferencingCode;
  78 }
  79
  80 TEST(WalkAST, DeclRef) {
  81   testWalk("int ^x;", "int y = ^x;");
  82   testWalk("int ^foo();", "int y = ^foo();");
  83   testWalk("namespace ns { int ^x; }", "int y = ns::^x;");
  84   testWalk("struct S { static int ^x; };", "int y = S::^x;");
  85   // Canonical declaration only.
  86   testWalk("extern int ^x; int x;", "int y = ^x;");
  87 }
  88
  89 TEST(WalkAST, TagType) {
  90   testWalk("struct ^S {};", "^S *y;");
  91   testWalk("enum ^E {};", "^E *y;");
  92   testWalk("struct ^S { static int x; };", "int y = ^S::x;");
  93 }
  94
  95 TEST(WalkAST, Alias) {
  96   testWalk(R"cpp(
  97     namespace ns { int x; }
  98     using ns::^x;
  99   )cpp",
 100            "int y = ^x;");
 101   testWalk(R"cpp(
 102     namespace ns { struct S; } // Not used
 103     using ns::S; // FIXME: S should be used
 104   )cpp",
 105            "^S *x;");
 106 }
 107
 108 } // namespace
 109 } // namespace include_cleaner
 110 } // namespace clang