llvm-project/clang-tools-extra/clangd/refactor/InsertionPoint.cpp

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5.3 KiB
C++

//===--- InsertionPoint.cpp - Where should we add new code? ---------------===//
//
// 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 "refactor/InsertionPoint.h"
#include "support/Logger.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/Basic/SourceManager.h"
namespace clang {
namespace clangd {
namespace {
// Choose the decl to insert before, according to an anchor.
// Nullptr means insert at end of DC.
// None means no valid place to insert.
llvm::Optional<const Decl *> insertionDecl(const DeclContext &DC,
const Anchor &A) {
bool LastMatched = false;
bool ReturnNext = false;
for (const auto *D : DC.decls()) {
if (D->isImplicit())
continue;
if (ReturnNext)
return D;
const Decl *NonTemplate = D;
if (auto *TD = llvm::dyn_cast<TemplateDecl>(D))
NonTemplate = TD->getTemplatedDecl();
bool Matches = A.Match(NonTemplate);
dlog(" {0} {1} {2}", Matches, D->getDeclKindName(), D);
switch (A.Direction) {
case Anchor::Above:
if (Matches && !LastMatched) {
// Special case: if "above" matches an access specifier, we actually
// want to insert below it!
if (llvm::isa<AccessSpecDecl>(D)) {
ReturnNext = true;
continue;
}
return D;
}
break;
case Anchor::Below:
if (LastMatched && !Matches)
return D;
break;
}
LastMatched = Matches;
}
if (ReturnNext || (LastMatched && A.Direction == Anchor::Below))
return nullptr;
return llvm::None;
}
SourceLocation beginLoc(const Decl &D) {
auto Loc = D.getBeginLoc();
if (RawComment *Comment = D.getASTContext().getRawCommentForDeclNoCache(&D)) {
auto CommentLoc = Comment->getBeginLoc();
if (CommentLoc.isValid() && Loc.isValid() &&
D.getASTContext().getSourceManager().isBeforeInTranslationUnit(
CommentLoc, Loc))
Loc = CommentLoc;
}
return Loc;
}
bool any(const Decl *D) { return true; }
SourceLocation endLoc(const DeclContext &DC) {
const Decl *D = llvm::cast<Decl>(&DC);
if (auto *OCD = llvm::dyn_cast<ObjCContainerDecl>(D))
return OCD->getAtEndRange().getBegin();
return D->getEndLoc();
}
AccessSpecifier getAccessAtEnd(const CXXRecordDecl &C) {
AccessSpecifier Spec = (C.getTagKind() == TTK_Class ? AS_private : AS_public);
for (const auto *D : C.decls())
if (const auto *ASD = llvm::dyn_cast<AccessSpecDecl>(D))
Spec = ASD->getAccess();
return Spec;
}
} // namespace
SourceLocation insertionPoint(const DeclContext &DC,
llvm::ArrayRef<Anchor> Anchors) {
dlog("Looking for insertion point in {0}", DC.getDeclKindName());
for (const auto &A : Anchors) {
dlog(" anchor ({0})", A.Direction == Anchor::Above ? "above" : "below");
if (auto D = insertionDecl(DC, A)) {
dlog(" anchor matched before {0}", *D);
return *D ? beginLoc(**D) : endLoc(DC);
}
}
dlog("no anchor matched");
return SourceLocation();
}
llvm::Expected<tooling::Replacement>
insertDecl(llvm::StringRef Code, const DeclContext &DC,
llvm::ArrayRef<Anchor> Anchors) {
auto Loc = insertionPoint(DC, Anchors);
// Fallback: insert at the end.
if (Loc.isInvalid())
Loc = endLoc(DC);
const auto &SM = DC.getParentASTContext().getSourceManager();
if (!SM.isWrittenInSameFile(Loc, cast<Decl>(DC).getLocation()))
return error("{0} body in wrong file: {1}", DC.getDeclKindName(),
Loc.printToString(SM));
return tooling::Replacement(SM, Loc, 0, Code);
}
SourceLocation insertionPoint(const CXXRecordDecl &InClass,
std::vector<Anchor> Anchors,
AccessSpecifier Protection) {
for (auto &A : Anchors)
A.Match = [Inner(std::move(A.Match)), Protection](const Decl *D) {
return D->getAccess() == Protection && Inner(D);
};
return insertionPoint(InClass, Anchors);
}
llvm::Expected<tooling::Replacement> insertDecl(llvm::StringRef Code,
const CXXRecordDecl &InClass,
std::vector<Anchor> Anchors,
AccessSpecifier Protection) {
// Fallback: insert at the bottom of the relevant access section.
Anchors.push_back({any, Anchor::Below});
auto Loc = insertionPoint(InClass, std::move(Anchors), Protection);
std::string CodeBuffer;
auto &SM = InClass.getASTContext().getSourceManager();
// Fallback: insert at the end of the class. Check if protection matches!
if (Loc.isInvalid()) {
Loc = InClass.getBraceRange().getEnd();
if (Protection != getAccessAtEnd(InClass)) {
CodeBuffer = (getAccessSpelling(Protection) + ":\n" + Code).str();
Code = CodeBuffer;
}
}
if (!SM.isWrittenInSameFile(Loc, InClass.getLocation()))
return error("Class body in wrong file: {0}", Loc.printToString(SM));
return tooling::Replacement(SM, Loc, 0, Code);
}
} // namespace clangd
} // namespace clang