//===--- Comment.cpp - Comment AST node implementation --------------------===//

//

// 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

//

//===----------------------------------------------------------------------===//

#include "clang/AST/Comment.h"

#include "clang/AST/ASTContext.h"

#include "clang/AST/Decl.h"

#include "clang/AST/DeclObjC.h"

#include "clang/AST/DeclTemplate.h"

#include "clang/Basic/CharInfo.h"

#include "llvm/Support/ErrorHandling.h"

#include <type_traits>

namespace clang {

namespace comments {

// Check that no comment class has a non-trival destructor. They are allocated

// with a BumpPtrAllocator and therefore their destructor is not executed.

#define ABSTRACT_COMMENT(COMMENT)

#define COMMENT(CLASS, PARENT)                                                 \

  static_assert(std::is_trivially_destructible<CLASS>::value,                  \

                #CLASS " should be trivially destructible!");

#include "clang/AST/CommentNodes.inc"

#undef COMMENT

#undef ABSTRACT_COMMENT

// DeclInfo is also allocated with a BumpPtrAllocator.

static_assert(std::is_trivially_destructible_v<DeclInfo>,

              "DeclInfo should be trivially destructible!");

const char *Comment::getCommentKindName() const {

  switch (getCommentKind()) {

  case CommentKind::None:

    return "None";

#define ABSTRACT_COMMENT(COMMENT)

#define COMMENT(CLASS, PARENT)                                                 \

  case CommentKind::CLASS:                                                     \

    return #CLASS;

#include "clang/AST/CommentNodes.inc"

#undef COMMENT

#undef ABSTRACT_COMMENT

  }

  llvm_unreachable("Unknown comment kind!");

}

namespace {

struct good {};

struct bad {};

template <typename T>

good implements_child_begin_end(Comment::child_iterator (T::*)() const) {

  return good();

}

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::VerbatimBlockLineComment>(clang::comments::Comment* const* (clang::comments::VerbatimBlockLineComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::TextComment>(clang::comments::Comment* const* (clang::comments::TextComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::InlineCommandComment>(clang::comments::Comment* const* (clang::comments::InlineCommandComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::HTMLStartTagComment>(clang::comments::Comment* const* (clang::comments::HTMLStartTagComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::HTMLEndTagComment>(clang::comments::Comment* const* (clang::comments::HTMLEndTagComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::FullComment>(clang::comments::Comment* const* (clang::comments::FullComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::ParagraphComment>(clang::comments::Comment* const* (clang::comments::ParagraphComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::BlockCommandComment>(clang::comments::Comment* const* (clang::comments::BlockCommandComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::VerbatimLineComment>(clang::comments::Comment* const* (clang::comments::VerbatimLineComment::*)() const)

Unexecuted instantiation: Comment.cpp:clang::comments::(anonymous namespace)::good clang::comments::(anonymous namespace)::implements_child_begin_end<clang::comments::VerbatimBlockComment>(clang::comments::Comment* const* (clang::comments::VerbatimBlockComment::*)() const)

LLVM_ATTRIBUTE_UNUSED

static inline bad implements_child_begin_end(

                      Comment::child_iterator (Comment::*)() const) {

  return bad();

}

#define ASSERT_IMPLEMENTS_child_begin(function) \

  (void) good(implements_child_begin_end(function))

LLVM_ATTRIBUTE_UNUSED

static inline void CheckCommentASTNodes() {

#define ABSTRACT_COMMENT(COMMENT)

#define COMMENT(CLASS, PARENT) \

  ASSERT_IMPLEMENTS_child_begin(&CLASS::child_begin); \

  ASSERT_IMPLEMENTS_child_begin(&CLASS::child_end);

#include "clang/AST/CommentNodes.inc"

#undef COMMENT

#undef ABSTRACT_COMMENT

}

#undef ASSERT_IMPLEMENTS_child_begin

} // end unnamed namespace

Comment::child_iterator Comment::child_begin() const {

  switch (getCommentKind()) {

  case CommentKind::None:

    llvm_unreachable("comment without a kind");

#define ABSTRACT_COMMENT(COMMENT)

#define COMMENT(CLASS, PARENT)                                                 \

  case CommentKind::CLASS:                                                     \

    return static_cast<const CLASS *>(this)->child_begin();

#include "clang/AST/CommentNodes.inc"

#undef COMMENT

#undef ABSTRACT_COMMENT

  }

  llvm_unreachable("Unknown comment kind!");

}

Comment::child_iterator Comment::child_end() const {

  switch (getCommentKind()) {

  case CommentKind::None:

    llvm_unreachable("comment without a kind");

#define ABSTRACT_COMMENT(COMMENT)

#define COMMENT(CLASS, PARENT)                                                 \

  case CommentKind::CLASS:                                                     \

    return static_cast<const CLASS *>(this)->child_end();

#include "clang/AST/CommentNodes.inc"

#undef COMMENT

#undef ABSTRACT_COMMENT

  }

  llvm_unreachable("Unknown comment kind!");

}

bool TextComment::isWhitespaceNoCache() const {

  return llvm::all_of(Text, clang::isWhitespace);

}

bool ParagraphComment::isWhitespaceNoCache() const {

  for (child_iterator I = child_begin(), E = child_end(); I != E; ++I) {

    if (const TextComment *TC = dyn_cast<TextComment>(*I)) {

      if (!TC->isWhitespace())

        return false;

    } else

      return false;

  }

  return true;

}

static TypeLoc lookThroughTypedefOrTypeAliasLocs(TypeLoc &SrcTL) {

  TypeLoc TL = SrcTL.IgnoreParens();

  // Look through attribute types.

  if (AttributedTypeLoc AttributeTL = TL.getAs<AttributedTypeLoc>())

    return AttributeTL.getModifiedLoc();

  // Look through qualified types.

  if (QualifiedTypeLoc QualifiedTL = TL.getAs<QualifiedTypeLoc>())

    return QualifiedTL.getUnqualifiedLoc();

  // Look through pointer types.

  if (PointerTypeLoc PointerTL = TL.getAs<PointerTypeLoc>())

    return PointerTL.getPointeeLoc().getUnqualifiedLoc();

  // Look through reference types.

  if (ReferenceTypeLoc ReferenceTL = TL.getAs<ReferenceTypeLoc>())

    return ReferenceTL.getPointeeLoc().getUnqualifiedLoc();

  // Look through adjusted types.

  if (AdjustedTypeLoc ATL = TL.getAs<AdjustedTypeLoc>())

    return ATL.getOriginalLoc();

  if (BlockPointerTypeLoc BlockPointerTL = TL.getAs<BlockPointerTypeLoc>())

    return BlockPointerTL.getPointeeLoc().getUnqualifiedLoc();

  if (MemberPointerTypeLoc MemberPointerTL = TL.getAs<MemberPointerTypeLoc>())

    return MemberPointerTL.getPointeeLoc().getUnqualifiedLoc();

  if (ElaboratedTypeLoc ETL = TL.getAs<ElaboratedTypeLoc>())

    return ETL.getNamedTypeLoc();

  return TL;

}

static bool getFunctionTypeLoc(TypeLoc TL, FunctionTypeLoc &ResFTL) {

  TypeLoc PrevTL;

  while (PrevTL != TL) {

    PrevTL = TL;

    TL = lookThroughTypedefOrTypeAliasLocs(TL);

  }

  if (FunctionTypeLoc FTL = TL.getAs<FunctionTypeLoc>()) {

    ResFTL = FTL;

    return true;

  }

  if (TemplateSpecializationTypeLoc STL =

          TL.getAs<TemplateSpecializationTypeLoc>()) {

    // If we have a typedef to a template specialization with exactly one

    // template argument of a function type, this looks like std::function,

    // boost::function, or other function wrapper.  Treat these typedefs as

    // functions.

    if (STL.getNumArgs() != 1)

      return false;

    TemplateArgumentLoc MaybeFunction = STL.getArgLoc(0);

    if (MaybeFunction.getArgument().getKind() != TemplateArgument::Type)

      return false;

    TypeSourceInfo *MaybeFunctionTSI = MaybeFunction.getTypeSourceInfo();

    TypeLoc TL = MaybeFunctionTSI->getTypeLoc().getUnqualifiedLoc();

    if (FunctionTypeLoc FTL = TL.getAs<FunctionTypeLoc>()) {

      ResFTL = FTL;

      return true;

    }

  }

  return false;

}

const char *

ParamCommandComment::getDirectionAsString(ParamCommandPassDirection D) {

  switch (D) {

  case ParamCommandPassDirection::In:

    return "[in]";

  case ParamCommandPassDirection::Out:

    return "[out]";

  case ParamCommandPassDirection::InOut:

    return "[in,out]";

  }

  llvm_unreachable("unknown PassDirection");

}

void DeclInfo::fill() {

  assert(!IsFilled);

  // Set defaults.

  Kind = OtherKind;

  TemplateKind = NotTemplate;

  IsObjCMethod = false;

  IsInstanceMethod = false;

  IsClassMethod = false;

  IsVariadic = false;

  ParamVars = std::nullopt;

  TemplateParameters = nullptr;

  if (!CommentDecl) {

    // If there is no declaration, the defaults is our only guess.

    IsFilled = true;

    return;

  }

  CurrentDecl = CommentDecl;

  Decl::Kind K = CommentDecl->getKind();

  const TypeSourceInfo *TSI = nullptr;

  switch (K) {

  default:

    // Defaults are should be good for declarations we don't handle explicitly.

    break;

  case Decl::Function:

  case Decl::CXXMethod:

  case Decl::CXXConstructor:

  case Decl::CXXDestructor:

  case Decl::CXXConversion: {

    const FunctionDecl *FD = cast<FunctionDecl>(CommentDecl);

    Kind = FunctionKind;

    ParamVars = FD->parameters();

    ReturnType = FD->getReturnType();

    unsigned NumLists = FD->getNumTemplateParameterLists();

    if (NumLists != 0) {

      TemplateKind = TemplateSpecialization;

      TemplateParameters =

          FD->getTemplateParameterList(NumLists - 1);

    }

    if (K == Decl::CXXMethod || K == Decl::CXXConstructor ||

        K == Decl::CXXDestructor || K == Decl::CXXConversion) {

      const CXXMethodDecl *MD = cast<CXXMethodDecl>(CommentDecl);

      IsInstanceMethod = MD->isInstance();

      IsClassMethod = !IsInstanceMethod;

    }

    IsVariadic = FD->isVariadic();

    assert(involvesFunctionType());

    break;

  }

  case Decl::ObjCMethod: {

    const ObjCMethodDecl *MD = cast<ObjCMethodDecl>(CommentDecl);

    Kind = FunctionKind;

    ParamVars = MD->parameters();

    ReturnType = MD->getReturnType();

    IsObjCMethod = true;

    IsInstanceMethod = MD->isInstanceMethod();

    IsClassMethod = !IsInstanceMethod;

    IsVariadic = MD->isVariadic();

    assert(involvesFunctionType());

    break;

  }

  case Decl::FunctionTemplate: {

    const FunctionTemplateDecl *FTD = cast<FunctionTemplateDecl>(CommentDecl);

    Kind = FunctionKind;

    TemplateKind = Template;

    const FunctionDecl *FD = FTD->getTemplatedDecl();

    ParamVars = FD->parameters();

    ReturnType = FD->getReturnType();

    TemplateParameters = FTD->getTemplateParameters();

    IsVariadic = FD->isVariadic();

    assert(involvesFunctionType());

    break;

  }

  case Decl::ClassTemplate: {

    const ClassTemplateDecl *CTD = cast<ClassTemplateDecl>(CommentDecl);

    Kind = ClassKind;

    TemplateKind = Template;

    TemplateParameters = CTD->getTemplateParameters();

    break;

  }

  case Decl::ClassTemplatePartialSpecialization: {

    const ClassTemplatePartialSpecializationDecl *CTPSD =

        cast<ClassTemplatePartialSpecializationDecl>(CommentDecl);

    Kind = ClassKind;

    TemplateKind = TemplatePartialSpecialization;

    TemplateParameters = CTPSD->getTemplateParameters();

    break;

  }

  case Decl::ClassTemplateSpecialization:

    Kind = ClassKind;

    TemplateKind = TemplateSpecialization;

    break;

  case Decl::Record:

  case Decl::CXXRecord:

    Kind = ClassKind;

    break;

  case Decl::Var:

    if (const VarTemplateDecl *VTD =

            cast<VarDecl>(CommentDecl)->getDescribedVarTemplate()) {

      TemplateKind = TemplateSpecialization;

      TemplateParameters = VTD->getTemplateParameters();

    }

    [[fallthrough]];

  case Decl::Field:

  case Decl::EnumConstant:

  case Decl::ObjCIvar:

  case Decl::ObjCAtDefsField:

  case Decl::ObjCProperty:

    if (const auto *VD = dyn_cast<DeclaratorDecl>(CommentDecl))

      TSI = VD->getTypeSourceInfo();

    else if (const auto *PD = dyn_cast<ObjCPropertyDecl>(CommentDecl))

      TSI = PD->getTypeSourceInfo();

    Kind = VariableKind;

    break;

  case Decl::VarTemplate: {

    const VarTemplateDecl *VTD = cast<VarTemplateDecl>(CommentDecl);

    Kind = VariableKind;

    TemplateKind = Template;

    TemplateParameters = VTD->getTemplateParameters();

    if (const VarDecl *VD = VTD->getTemplatedDecl())

      TSI = VD->getTypeSourceInfo();

    break;

  }

  case Decl::Namespace:

    Kind = NamespaceKind;

    break;

  case Decl::TypeAlias:

  case Decl::Typedef:

    Kind = TypedefKind;

    TSI = cast<TypedefNameDecl>(CommentDecl)->getTypeSourceInfo();

    break;

  case Decl::TypeAliasTemplate: {

    const TypeAliasTemplateDecl *TAT = cast<TypeAliasTemplateDecl>(CommentDecl);

    Kind = TypedefKind;

    TemplateKind = Template;

    TemplateParameters = TAT->getTemplateParameters();

    if (TypeAliasDecl *TAD = TAT->getTemplatedDecl())

      TSI = TAD->getTypeSourceInfo();

    break;

  }

  case Decl::Enum:

    Kind = EnumKind;

    break;

  }

  // If the type is a typedef / using to something we consider a function,

  // extract arguments and return type.

  if (TSI) {

    TypeLoc TL = TSI->getTypeLoc().getUnqualifiedLoc();

    FunctionTypeLoc FTL;

    if (getFunctionTypeLoc(TL, FTL)) {

      ParamVars = FTL.getParams();

      ReturnType = FTL.getReturnLoc().getType();

      if (const auto *FPT = dyn_cast<FunctionProtoType>(FTL.getTypePtr()))

        IsVariadic = FPT->isVariadic();

      assert(involvesFunctionType());

    }

  }

  IsFilled = true;

}

StringRef ParamCommandComment::getParamName(const FullComment *FC) const {

  assert(isParamIndexValid());

  if (isVarArgParam())

    return "...";

  return FC->getDeclInfo()->ParamVars[getParamIndex()]->getName();

}

StringRef TParamCommandComment::getParamName(const FullComment *FC) const {

  assert(isPositionValid());

  const TemplateParameterList *TPL = FC->getDeclInfo()->TemplateParameters;

  for (unsigned i = 0, e = getDepth(); i != e; ++i) {

    assert(TPL && "Unknown TemplateParameterList");

    if (i == e - 1)

      return TPL->getParam(getIndex(i))->getName();

    const NamedDecl *Param = TPL->getParam(getIndex(i));

    if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param))

      TPL = TTP->getTemplateParameters();

  }

  return "";

}

} // end namespace comments

} // end namespace clang