llvm-project/clang-tools-extra/change-namespace/ChangeNamespace.cpp

769 lines
33 KiB
C++

//===-- ChangeNamespace.cpp - Change namespace implementation -------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "ChangeNamespace.h"
#include "clang/Format/Format.h"
#include "clang/Lex/Lexer.h"
#include "llvm/Support/ErrorHandling.h"
using namespace clang::ast_matchers;
namespace clang {
namespace change_namespace {
namespace {
inline std::string
joinNamespaces(const llvm::SmallVectorImpl<StringRef> &Namespaces) {
if (Namespaces.empty())
return "";
std::string Result = Namespaces.front();
for (auto I = Namespaces.begin() + 1, E = Namespaces.end(); I != E; ++I)
Result += ("::" + *I).str();
return Result;
}
SourceLocation startLocationForType(TypeLoc TLoc) {
// For elaborated types (e.g. `struct a::A`) we want the portion after the
// `struct` but including the namespace qualifier, `a::`.
if (TLoc.getTypeLocClass() == TypeLoc::Elaborated) {
NestedNameSpecifierLoc NestedNameSpecifier =
TLoc.castAs<ElaboratedTypeLoc>().getQualifierLoc();
if (NestedNameSpecifier.getNestedNameSpecifier())
return NestedNameSpecifier.getBeginLoc();
TLoc = TLoc.getNextTypeLoc();
}
return TLoc.getLocStart();
}
SourceLocation EndLocationForType(TypeLoc TLoc) {
// Dig past any namespace or keyword qualifications.
while (TLoc.getTypeLocClass() == TypeLoc::Elaborated ||
TLoc.getTypeLocClass() == TypeLoc::Qualified)
TLoc = TLoc.getNextTypeLoc();
// The location for template specializations (e.g. Foo<int>) includes the
// templated types in its location range. We want to restrict this to just
// before the `<` character.
if (TLoc.getTypeLocClass() == TypeLoc::TemplateSpecialization)
return TLoc.castAs<TemplateSpecializationTypeLoc>()
.getLAngleLoc()
.getLocWithOffset(-1);
return TLoc.getEndLoc();
}
// Returns the containing namespace of `InnerNs` by skipping `PartialNsName`.
// If the `InnerNs` does not have `PartialNsName` as suffix, or `PartialNsName`
// is empty, nullptr is returned.
// For example, if `InnerNs` is "a::b::c" and `PartialNsName` is "b::c", then
// the NamespaceDecl of namespace "a" will be returned.
const NamespaceDecl *getOuterNamespace(const NamespaceDecl *InnerNs,
llvm::StringRef PartialNsName) {
if (!InnerNs || PartialNsName.empty())
return nullptr;
const auto *CurrentContext = llvm::cast<DeclContext>(InnerNs);
const auto *CurrentNs = InnerNs;
llvm::SmallVector<llvm::StringRef, 4> PartialNsNameSplitted;
PartialNsName.split(PartialNsNameSplitted, "::", /*MaxSplit=*/-1,
/*KeepEmpty=*/false);
while (!PartialNsNameSplitted.empty()) {
// Get the inner-most namespace in CurrentContext.
while (CurrentContext && !llvm::isa<NamespaceDecl>(CurrentContext))
CurrentContext = CurrentContext->getParent();
if (!CurrentContext)
return nullptr;
CurrentNs = llvm::cast<NamespaceDecl>(CurrentContext);
if (PartialNsNameSplitted.back() != CurrentNs->getNameAsString())
return nullptr;
PartialNsNameSplitted.pop_back();
CurrentContext = CurrentContext->getParent();
}
return CurrentNs;
}
static std::unique_ptr<Lexer>
getLexerStartingFromLoc(SourceLocation Loc, const SourceManager &SM,
const LangOptions &LangOpts) {
if (Loc.isMacroID() &&
!Lexer::isAtEndOfMacroExpansion(Loc, SM, LangOpts, &Loc))
return nullptr;
// Break down the source location.
std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
// Try to load the file buffer.
bool InvalidTemp = false;
llvm::StringRef File = SM.getBufferData(LocInfo.first, &InvalidTemp);
if (InvalidTemp)
return nullptr;
const char *TokBegin = File.data() + LocInfo.second;
// Lex from the start of the given location.
return llvm::make_unique<Lexer>(SM.getLocForStartOfFile(LocInfo.first),
LangOpts, File.begin(), TokBegin, File.end());
}
// FIXME: get rid of this helper function if this is supported in clang-refactor
// library.
static SourceLocation getStartOfNextLine(SourceLocation Loc,
const SourceManager &SM,
const LangOptions &LangOpts) {
std::unique_ptr<Lexer> Lex = getLexerStartingFromLoc(Loc, SM, LangOpts);
if (!Lex.get())
return SourceLocation();
llvm::SmallVector<char, 16> Line;
// FIXME: this is a bit hacky to get ReadToEndOfLine work.
Lex->setParsingPreprocessorDirective(true);
Lex->ReadToEndOfLine(&Line);
auto End = Loc.getLocWithOffset(Line.size());
return SM.getLocForEndOfFile(SM.getDecomposedLoc(Loc).first) == End
? End
: End.getLocWithOffset(1);
}
// Returns `R` with new range that refers to code after `Replaces` being
// applied.
tooling::Replacement
getReplacementInChangedCode(const tooling::Replacements &Replaces,
const tooling::Replacement &R) {
unsigned NewStart = Replaces.getShiftedCodePosition(R.getOffset());
unsigned NewEnd =
Replaces.getShiftedCodePosition(R.getOffset() + R.getLength());
return tooling::Replacement(R.getFilePath(), NewStart, NewEnd - NewStart,
R.getReplacementText());
}
// Adds a replacement `R` into `Replaces` or merges it into `Replaces` by
// applying all existing Replaces first if there is conflict.
void addOrMergeReplacement(const tooling::Replacement &R,
tooling::Replacements *Replaces) {
auto Err = Replaces->add(R);
if (Err) {
llvm::consumeError(std::move(Err));
auto Replace = getReplacementInChangedCode(*Replaces, R);
*Replaces = Replaces->merge(tooling::Replacements(Replace));
}
}
tooling::Replacement createReplacement(SourceLocation Start, SourceLocation End,
llvm::StringRef ReplacementText,
const SourceManager &SM) {
if (!Start.isValid() || !End.isValid()) {
llvm::errs() << "start or end location were invalid\n";
return tooling::Replacement();
}
if (SM.getDecomposedLoc(Start).first != SM.getDecomposedLoc(End).first) {
llvm::errs()
<< "start or end location were in different macro expansions\n";
return tooling::Replacement();
}
Start = SM.getSpellingLoc(Start);
End = SM.getSpellingLoc(End);
if (SM.getFileID(Start) != SM.getFileID(End)) {
llvm::errs() << "start or end location were in different files\n";
return tooling::Replacement();
}
return tooling::Replacement(
SM, CharSourceRange::getTokenRange(SM.getSpellingLoc(Start),
SM.getSpellingLoc(End)),
ReplacementText);
}
tooling::Replacement createInsertion(SourceLocation Loc,
llvm::StringRef InsertText,
const SourceManager &SM) {
if (Loc.isInvalid()) {
llvm::errs() << "insert Location is invalid.\n";
return tooling::Replacement();
}
Loc = SM.getSpellingLoc(Loc);
return tooling::Replacement(SM, Loc, 0, InsertText);
}
// Returns the shortest qualified name for declaration `DeclName` in the
// namespace `NsName`. For example, if `DeclName` is "a::b::X" and `NsName`
// is "a::c::d", then "b::X" will be returned.
// \param DeclName A fully qualified name, "::a::b::X" or "a::b::X".
// \param NsName A fully qualified name, "::a::b" or "a::b". Global namespace
// will have empty name.
std::string getShortestQualifiedNameInNamespace(llvm::StringRef DeclName,
llvm::StringRef NsName) {
DeclName = DeclName.ltrim(':');
NsName = NsName.ltrim(':');
if (DeclName.find(':') == llvm::StringRef::npos)
return DeclName;
while (!DeclName.consume_front((NsName + "::").str())) {
const auto Pos = NsName.find_last_of(':');
if (Pos == llvm::StringRef::npos)
return DeclName;
assert(Pos > 0);
NsName = NsName.substr(0, Pos - 1);
}
return DeclName;
}
std::string wrapCodeInNamespace(StringRef NestedNs, std::string Code) {
if (Code.back() != '\n')
Code += "\n";
llvm::SmallVector<StringRef, 4> NsSplitted;
NestedNs.split(NsSplitted, "::");
while (!NsSplitted.empty()) {
// FIXME: consider code style for comments.
Code = ("namespace " + NsSplitted.back() + " {\n" + Code +
"} // namespace " + NsSplitted.back() + "\n")
.str();
NsSplitted.pop_back();
}
return Code;
}
// Returns true if \p D is a nested DeclContext in \p Context
bool isNestedDeclContext(const DeclContext *D, const DeclContext *Context) {
while (D) {
if (D == Context)
return true;
D = D->getParent();
}
return false;
}
// Returns true if \p D is visible at \p Loc with DeclContext \p DeclCtx.
bool isDeclVisibleAtLocation(const SourceManager &SM, const Decl *D,
const DeclContext *DeclCtx, SourceLocation Loc) {
SourceLocation DeclLoc = SM.getSpellingLoc(D->getLocation());
Loc = SM.getSpellingLoc(Loc);
return SM.isBeforeInTranslationUnit(DeclLoc, Loc) &&
(SM.getFileID(DeclLoc) == SM.getFileID(Loc) &&
isNestedDeclContext(DeclCtx, D->getDeclContext()));
}
} // anonymous namespace
ChangeNamespaceTool::ChangeNamespaceTool(
llvm::StringRef OldNs, llvm::StringRef NewNs, llvm::StringRef FilePattern,
std::map<std::string, tooling::Replacements> *FileToReplacements,
llvm::StringRef FallbackStyle)
: FallbackStyle(FallbackStyle), FileToReplacements(*FileToReplacements),
OldNamespace(OldNs.ltrim(':')), NewNamespace(NewNs.ltrim(':')),
FilePattern(FilePattern) {
FileToReplacements->clear();
llvm::SmallVector<llvm::StringRef, 4> OldNsSplitted;
llvm::SmallVector<llvm::StringRef, 4> NewNsSplitted;
llvm::StringRef(OldNamespace).split(OldNsSplitted, "::");
llvm::StringRef(NewNamespace).split(NewNsSplitted, "::");
// Calculates `DiffOldNamespace` and `DiffNewNamespace`.
while (!OldNsSplitted.empty() && !NewNsSplitted.empty() &&
OldNsSplitted.front() == NewNsSplitted.front()) {
OldNsSplitted.erase(OldNsSplitted.begin());
NewNsSplitted.erase(NewNsSplitted.begin());
}
DiffOldNamespace = joinNamespaces(OldNsSplitted);
DiffNewNamespace = joinNamespaces(NewNsSplitted);
}
void ChangeNamespaceTool::registerMatchers(ast_matchers::MatchFinder *Finder) {
std::string FullOldNs = "::" + OldNamespace;
// Prefix is the outer-most namespace in DiffOldNamespace. For example, if the
// OldNamespace is "a::b::c" and DiffOldNamespace is "b::c", then Prefix will
// be "a::b". Declarations in this namespace will not be visible in the new
// namespace. If DiffOldNamespace is empty, Prefix will be a invalid name "-".
llvm::SmallVector<llvm::StringRef, 4> DiffOldNsSplitted;
llvm::StringRef(DiffOldNamespace).split(DiffOldNsSplitted, "::");
std::string Prefix = "-";
if (!DiffOldNsSplitted.empty())
Prefix = (StringRef(FullOldNs).drop_back(DiffOldNamespace.size()) +
DiffOldNsSplitted.front())
.str();
auto IsInMovedNs =
allOf(hasAncestor(namespaceDecl(hasName(FullOldNs)).bind("ns_decl")),
isExpansionInFileMatching(FilePattern));
auto IsVisibleInNewNs = anyOf(
IsInMovedNs, unless(hasAncestor(namespaceDecl(hasName(Prefix)))));
// Match using declarations.
Finder->addMatcher(
usingDecl(isExpansionInFileMatching(FilePattern), IsVisibleInNewNs)
.bind("using"),
this);
// Match using namespace declarations.
Finder->addMatcher(usingDirectiveDecl(isExpansionInFileMatching(FilePattern),
IsVisibleInNewNs)
.bind("using_namespace"),
this);
// Match old namespace blocks.
Finder->addMatcher(
namespaceDecl(hasName(FullOldNs), isExpansionInFileMatching(FilePattern))
.bind("old_ns"),
this);
// Match forward-declarations in the old namespace.
Finder->addMatcher(
cxxRecordDecl(unless(anyOf(isImplicit(), isDefinition())), IsInMovedNs)
.bind("fwd_decl"),
this);
// Match references to types that are not defined in the old namespace.
// Forward-declarations in the old namespace are also matched since they will
// be moved back to the old namespace.
auto DeclMatcher = namedDecl(
hasAncestor(namespaceDecl()),
unless(anyOf(
isImplicit(), hasAncestor(namespaceDecl(isAnonymous())),
hasAncestor(cxxRecordDecl()),
allOf(IsInMovedNs, unless(cxxRecordDecl(unless(isDefinition())))))));
// Match TypeLocs on the declaration. Carefully match only the outermost
// TypeLoc and template specialization arguments (which are not outermost)
// that are directly linked to types matching `DeclMatcher`. Nested name
// specifier locs are handled separately below.
Finder->addMatcher(
typeLoc(IsInMovedNs,
loc(qualType(hasDeclaration(DeclMatcher.bind("from_decl")))),
unless(anyOf(hasParent(typeLoc(loc(qualType(
allOf(hasDeclaration(DeclMatcher),
unless(templateSpecializationType())))))),
hasParent(nestedNameSpecifierLoc()))),
hasAncestor(decl().bind("dc")))
.bind("type"),
this);
// Types in `UsingShadowDecl` is not matched by `typeLoc` above, so we need to
// special case it.
Finder->addMatcher(usingDecl(IsInMovedNs, hasAnyUsingShadowDecl(decl()))
.bind("using_with_shadow"),
this);
// Handle types in nested name specifier. Specifiers that are in a TypeLoc
// matched above are not matched, e.g. "A::" in "A::A" is not matched since
// "A::A" would have already been fixed.
Finder->addMatcher(nestedNameSpecifierLoc(
hasAncestor(decl(IsInMovedNs).bind("dc")),
loc(nestedNameSpecifier(specifiesType(
hasDeclaration(DeclMatcher.bind("from_decl"))))),
unless(hasAncestor(typeLoc(loc(qualType(hasDeclaration(
decl(equalsBoundNode("from_decl")))))))))
.bind("nested_specifier_loc"),
this);
// Matches base class initializers in constructors. TypeLocs of base class
// initializers do not need to be fixed. For example,
// class X : public a::b::Y {
// public:
// X() : Y::Y() {} // Y::Y do not need namespace specifier.
// };
Finder->addMatcher(
cxxCtorInitializer(isBaseInitializer()).bind("base_initializer"), this);
// Handle function.
// Only handle functions that are defined in a namespace excluding member
// function, static methods (qualified by nested specifier), and functions
// defined in the global namespace.
// Note that the matcher does not exclude calls to out-of-line static method
// definitions, so we need to exclude them in the callback handler.
auto FuncMatcher =
functionDecl(unless(anyOf(cxxMethodDecl(), IsInMovedNs,
hasAncestor(namespaceDecl(isAnonymous())),
hasAncestor(cxxRecordDecl()))),
hasParent(namespaceDecl()));
Finder->addMatcher(
decl(forEachDescendant(callExpr(callee(FuncMatcher)).bind("call")),
IsInMovedNs, unless(isImplicit()))
.bind("dc"),
this);
auto GlobalVarMatcher = varDecl(
hasGlobalStorage(), hasParent(namespaceDecl()),
unless(anyOf(IsInMovedNs, hasAncestor(namespaceDecl(isAnonymous())))));
Finder->addMatcher(declRefExpr(IsInMovedNs, hasAncestor(decl().bind("dc")),
to(GlobalVarMatcher.bind("var_decl")))
.bind("var_ref"),
this);
}
void ChangeNamespaceTool::run(
const ast_matchers::MatchFinder::MatchResult &Result) {
if (const auto *Using = Result.Nodes.getNodeAs<UsingDecl>("using")) {
UsingDecls.insert(Using);
} else if (const auto *UsingNamespace =
Result.Nodes.getNodeAs<UsingDirectiveDecl>(
"using_namespace")) {
UsingNamespaceDecls.insert(UsingNamespace);
} else if (const auto *NsDecl =
Result.Nodes.getNodeAs<NamespaceDecl>("old_ns")) {
moveOldNamespace(Result, NsDecl);
} else if (const auto *FwdDecl =
Result.Nodes.getNodeAs<CXXRecordDecl>("fwd_decl")) {
moveClassForwardDeclaration(Result, FwdDecl);
} else if (const auto *UsingWithShadow =
Result.Nodes.getNodeAs<UsingDecl>("using_with_shadow")) {
fixUsingShadowDecl(Result, UsingWithShadow);
} else if (const auto *Specifier =
Result.Nodes.getNodeAs<NestedNameSpecifierLoc>(
"nested_specifier_loc")) {
SourceLocation Start = Specifier->getBeginLoc();
SourceLocation End = EndLocationForType(Specifier->getTypeLoc());
fixTypeLoc(Result, Start, End, Specifier->getTypeLoc());
} else if (const auto *BaseInitializer =
Result.Nodes.getNodeAs<CXXCtorInitializer>(
"base_initializer")) {
BaseCtorInitializerTypeLocs.push_back(
BaseInitializer->getTypeSourceInfo()->getTypeLoc());
} else if (const auto *TLoc = Result.Nodes.getNodeAs<TypeLoc>("type")) {
fixTypeLoc(Result, startLocationForType(*TLoc), EndLocationForType(*TLoc),
*TLoc);
} else if (const auto *VarRef =
Result.Nodes.getNodeAs<DeclRefExpr>("var_ref")) {
const auto *Var = Result.Nodes.getNodeAs<VarDecl>("var_decl");
assert(Var);
if (Var->getCanonicalDecl()->isStaticDataMember())
return;
const clang::Decl *Context = Result.Nodes.getNodeAs<clang::Decl>("dc");
assert(Context && "Empty decl context.");
clang::SourceRange VarRefRange = VarRef->getSourceRange();
replaceQualifiedSymbolInDeclContext(
Result, Context->getDeclContext(), VarRefRange.getBegin(),
VarRefRange.getEnd(), llvm::cast<NamedDecl>(Var));
} else {
const auto *Call = Result.Nodes.getNodeAs<clang::CallExpr>("call");
assert(Call != nullptr && "Expecting callback for CallExpr.");
const clang::FunctionDecl *Func = Call->getDirectCallee();
assert(Func != nullptr);
// Ignore out-of-line static methods since they will be handled by nested
// name specifiers.
if (Func->getCanonicalDecl()->getStorageClass() ==
clang::StorageClass::SC_Static &&
Func->isOutOfLine())
return;
const clang::Decl *Context = Result.Nodes.getNodeAs<clang::Decl>("dc");
assert(Context && "Empty decl context.");
clang::SourceRange CalleeRange = Call->getCallee()->getSourceRange();
replaceQualifiedSymbolInDeclContext(
Result, Context->getDeclContext(), CalleeRange.getBegin(),
CalleeRange.getEnd(), llvm::cast<NamedDecl>(Func));
}
}
static SourceLocation getLocAfterNamespaceLBrace(const NamespaceDecl *NsDecl,
const SourceManager &SM,
const LangOptions &LangOpts) {
std::unique_ptr<Lexer> Lex =
getLexerStartingFromLoc(NsDecl->getLocStart(), SM, LangOpts);
assert(Lex.get() &&
"Failed to create lexer from the beginning of namespace.");
if (!Lex.get())
return SourceLocation();
Token Tok;
while (!Lex->LexFromRawLexer(Tok) && Tok.isNot(tok::TokenKind::l_brace)) {
}
return Tok.isNot(tok::TokenKind::l_brace)
? SourceLocation()
: Tok.getEndLoc().getLocWithOffset(1);
}
// Stores information about a moved namespace in `MoveNamespaces` and leaves
// the actual movement to `onEndOfTranslationUnit()`.
void ChangeNamespaceTool::moveOldNamespace(
const ast_matchers::MatchFinder::MatchResult &Result,
const NamespaceDecl *NsDecl) {
// If the namespace is empty, do nothing.
if (Decl::castToDeclContext(NsDecl)->decls_empty())
return;
// Get the range of the code in the old namespace.
SourceLocation Start = getLocAfterNamespaceLBrace(
NsDecl, *Result.SourceManager, Result.Context->getLangOpts());
assert(Start.isValid() && "Can't find l_brace for namespace.");
SourceLocation End = NsDecl->getRBraceLoc().getLocWithOffset(-1);
// Create a replacement that deletes the code in the old namespace merely for
// retrieving offset and length from it.
const auto R = createReplacement(Start, End, "", *Result.SourceManager);
MoveNamespace MoveNs;
MoveNs.Offset = R.getOffset();
MoveNs.Length = R.getLength();
// Insert the new namespace after `DiffOldNamespace`. For example, if
// `OldNamespace` is "a::b::c" and `NewNamespace` is `a::x::y`, then
// "x::y" will be inserted inside the existing namespace "a" and after "a::b".
// `OuterNs` is the first namespace in `DiffOldNamespace`, e.g. "namespace b"
// in the above example.
// If there is no outer namespace (i.e. DiffOldNamespace is empty), the new
// namespace will be a nested namespace in the old namespace.
const NamespaceDecl *OuterNs = getOuterNamespace(NsDecl, DiffOldNamespace);
SourceLocation InsertionLoc = Start;
if (OuterNs) {
SourceLocation LocAfterNs =
getStartOfNextLine(OuterNs->getRBraceLoc(), *Result.SourceManager,
Result.Context->getLangOpts());
assert(LocAfterNs.isValid() &&
"Failed to get location after DiffOldNamespace");
InsertionLoc = LocAfterNs;
}
MoveNs.InsertionOffset = Result.SourceManager->getFileOffset(
Result.SourceManager->getSpellingLoc(InsertionLoc));
MoveNs.FID = Result.SourceManager->getFileID(Start);
MoveNs.SourceMgr = Result.SourceManager;
MoveNamespaces[R.getFilePath()].push_back(MoveNs);
}
// Removes a class forward declaration from the code in the moved namespace and
// creates an `InsertForwardDeclaration` to insert the forward declaration back
// into the old namespace after moving code from the old namespace to the new
// namespace.
// For example, changing "a" to "x":
// Old code:
// namespace a {
// class FWD;
// class A { FWD *fwd; }
// } // a
// New code:
// namespace a {
// class FWD;
// } // a
// namespace x {
// class A { a::FWD *fwd; }
// } // x
void ChangeNamespaceTool::moveClassForwardDeclaration(
const ast_matchers::MatchFinder::MatchResult &Result,
const CXXRecordDecl *FwdDecl) {
SourceLocation Start = FwdDecl->getLocStart();
SourceLocation End = FwdDecl->getLocEnd();
SourceLocation AfterSemi = Lexer::findLocationAfterToken(
End, tok::semi, *Result.SourceManager, Result.Context->getLangOpts(),
/*SkipTrailingWhitespaceAndNewLine=*/true);
if (AfterSemi.isValid())
End = AfterSemi.getLocWithOffset(-1);
// Delete the forward declaration from the code to be moved.
const auto Deletion =
createReplacement(Start, End, "", *Result.SourceManager);
auto Err = FileToReplacements[Deletion.getFilePath()].add(Deletion);
if (Err)
llvm_unreachable(llvm::toString(std::move(Err)).c_str());
llvm::StringRef Code = Lexer::getSourceText(
CharSourceRange::getTokenRange(
Result.SourceManager->getSpellingLoc(Start),
Result.SourceManager->getSpellingLoc(End)),
*Result.SourceManager, Result.Context->getLangOpts());
// Insert the forward declaration back into the old namespace after moving the
// code from old namespace to new namespace.
// Insertion information is stored in `InsertFwdDecls` and actual
// insertion will be performed in `onEndOfTranslationUnit`.
// Get the (old) namespace that contains the forward declaration.
const auto *NsDecl = Result.Nodes.getNodeAs<NamespaceDecl>("ns_decl");
// The namespace contains the forward declaration, so it must not be empty.
assert(!NsDecl->decls_empty());
const auto Insertion = createInsertion(NsDecl->decls_begin()->getLocStart(),
Code, *Result.SourceManager);
InsertForwardDeclaration InsertFwd;
InsertFwd.InsertionOffset = Insertion.getOffset();
InsertFwd.ForwardDeclText = Insertion.getReplacementText().str();
InsertFwdDecls[Insertion.getFilePath()].push_back(InsertFwd);
}
// Replaces a qualified symbol (in \p DeclCtx) that refers to a declaration \p
// FromDecl with the shortest qualified name possible when the reference is in
// `NewNamespace`.
void ChangeNamespaceTool::replaceQualifiedSymbolInDeclContext(
const ast_matchers::MatchFinder::MatchResult &Result,
const DeclContext *DeclCtx, SourceLocation Start, SourceLocation End,
const NamedDecl *FromDecl) {
const auto *NsDeclContext = DeclCtx->getEnclosingNamespaceContext();
const auto *NsDecl = llvm::cast<NamespaceDecl>(NsDeclContext);
// Calculate the name of the `NsDecl` after it is moved to new namespace.
std::string OldNs = NsDecl->getQualifiedNameAsString();
llvm::StringRef Postfix = OldNs;
bool Consumed = Postfix.consume_front(OldNamespace);
assert(Consumed && "Expect OldNS to start with OldNamespace.");
(void)Consumed;
const std::string NewNs = (NewNamespace + Postfix).str();
llvm::StringRef NestedName = Lexer::getSourceText(
CharSourceRange::getTokenRange(
Result.SourceManager->getSpellingLoc(Start),
Result.SourceManager->getSpellingLoc(End)),
*Result.SourceManager, Result.Context->getLangOpts());
// If the symbol is already fully qualified, no change needs to be make.
if (NestedName.startswith("::"))
return;
std::string FromDeclName = FromDecl->getQualifiedNameAsString();
std::string ReplaceName =
getShortestQualifiedNameInNamespace(FromDeclName, NewNs);
// Checks if there is any using namespace declarations that can shorten the
// qualified name.
for (const auto *UsingNamespace : UsingNamespaceDecls) {
if (!isDeclVisibleAtLocation(*Result.SourceManager, UsingNamespace, DeclCtx,
Start))
continue;
StringRef FromDeclNameRef = FromDeclName;
if (FromDeclNameRef.consume_front(UsingNamespace->getNominatedNamespace()
->getQualifiedNameAsString())) {
FromDeclNameRef = FromDeclNameRef.drop_front(2);
if (FromDeclNameRef.size() < ReplaceName.size())
ReplaceName = FromDeclNameRef;
}
}
// Checks if there is any using shadow declarations that can shorten the
// qualified name.
bool Matched = false;
for (const UsingDecl *Using : UsingDecls) {
if (Matched)
break;
if (isDeclVisibleAtLocation(*Result.SourceManager, Using, DeclCtx, Start)) {
for (const auto *UsingShadow : Using->shadows()) {
const auto *TargetDecl = UsingShadow->getTargetDecl();
if (TargetDecl == FromDecl) {
ReplaceName = FromDecl->getNameAsString();
Matched = true;
break;
}
}
}
}
// If the new nested name in the new namespace is the same as it was in the
// old namespace, we don't create replacement.
if (NestedName == ReplaceName)
return;
auto R = createReplacement(Start, End, ReplaceName, *Result.SourceManager);
auto Err = FileToReplacements[R.getFilePath()].add(R);
if (Err)
llvm_unreachable(llvm::toString(std::move(Err)).c_str());
}
// Replace the [Start, End] of `Type` with the shortest qualified name when the
// `Type` is in `NewNamespace`.
void ChangeNamespaceTool::fixTypeLoc(
const ast_matchers::MatchFinder::MatchResult &Result, SourceLocation Start,
SourceLocation End, TypeLoc Type) {
// FIXME: do not rename template parameter.
if (Start.isInvalid() || End.isInvalid())
return;
// Types of CXXCtorInitializers do not need to be fixed.
if (llvm::is_contained(BaseCtorInitializerTypeLocs, Type))
return;
// The declaration which this TypeLoc refers to.
const auto *FromDecl = Result.Nodes.getNodeAs<NamedDecl>("from_decl");
// `hasDeclaration` gives underlying declaration, but if the type is
// a typedef type, we need to use the typedef type instead.
if (auto *Typedef = Type.getType()->getAs<TypedefType>()) {
FromDecl = Typedef->getDecl();
auto IsInMovedNs = [&](const NamedDecl *D) {
if (!llvm::StringRef(D->getQualifiedNameAsString())
.startswith(OldNamespace + "::"))
return false;
auto ExpansionLoc =
Result.SourceManager->getExpansionLoc(D->getLocStart());
if (ExpansionLoc.isInvalid())
return false;
llvm::StringRef Filename =
Result.SourceManager->getFilename(ExpansionLoc);
llvm::Regex RE(FilePattern);
return RE.match(Filename);
};
// Don't fix the \p Type if it refers to a type alias decl in the moved
// namespace since the alias decl will be moved along with the type
// reference.
if (IsInMovedNs(FromDecl))
return;
}
const Decl *DeclCtx = Result.Nodes.getNodeAs<Decl>("dc");
assert(DeclCtx && "Empty decl context.");
replaceQualifiedSymbolInDeclContext(Result, DeclCtx->getDeclContext(), Start,
End, FromDecl);
}
void ChangeNamespaceTool::fixUsingShadowDecl(
const ast_matchers::MatchFinder::MatchResult &Result,
const UsingDecl *UsingDeclaration) {
SourceLocation Start = UsingDeclaration->getLocStart();
SourceLocation End = UsingDeclaration->getLocEnd();
if (Start.isInvalid() || End.isInvalid())
return;
assert(UsingDeclaration->shadow_size() > 0);
// FIXME: it might not be always accurate to use the first using-decl.
const NamedDecl *TargetDecl =
UsingDeclaration->shadow_begin()->getTargetDecl();
std::string TargetDeclName = TargetDecl->getQualifiedNameAsString();
// FIXME: check if target_decl_name is in moved ns, which doesn't make much
// sense. If this happens, we need to use name with the new namespace.
// Use fully qualified name in UsingDecl for now.
auto R = createReplacement(Start, End, "using ::" + TargetDeclName,
*Result.SourceManager);
auto Err = FileToReplacements[R.getFilePath()].add(R);
if (Err)
llvm_unreachable(llvm::toString(std::move(Err)).c_str());
}
void ChangeNamespaceTool::onEndOfTranslationUnit() {
// Move namespace blocks and insert forward declaration to old namespace.
for (const auto &FileAndNsMoves : MoveNamespaces) {
auto &NsMoves = FileAndNsMoves.second;
if (NsMoves.empty())
continue;
const std::string &FilePath = FileAndNsMoves.first;
auto &Replaces = FileToReplacements[FilePath];
auto &SM = *NsMoves.begin()->SourceMgr;
llvm::StringRef Code = SM.getBufferData(NsMoves.begin()->FID);
auto ChangedCode = tooling::applyAllReplacements(Code, Replaces);
if (!ChangedCode) {
llvm::errs() << llvm::toString(ChangedCode.takeError()) << "\n";
continue;
}
// Replacements on the changed code for moving namespaces and inserting
// forward declarations to old namespaces.
tooling::Replacements NewReplacements;
// Cut the changed code from the old namespace and paste the code in the new
// namespace.
for (const auto &NsMove : NsMoves) {
// Calculate the range of the old namespace block in the changed
// code.
const unsigned NewOffset = Replaces.getShiftedCodePosition(NsMove.Offset);
const unsigned NewLength =
Replaces.getShiftedCodePosition(NsMove.Offset + NsMove.Length) -
NewOffset;
tooling::Replacement Deletion(FilePath, NewOffset, NewLength, "");
std::string MovedCode = ChangedCode->substr(NewOffset, NewLength);
std::string MovedCodeWrappedInNewNs =
wrapCodeInNamespace(DiffNewNamespace, MovedCode);
// Calculate the new offset at which the code will be inserted in the
// changed code.
unsigned NewInsertionOffset =
Replaces.getShiftedCodePosition(NsMove.InsertionOffset);
tooling::Replacement Insertion(FilePath, NewInsertionOffset, 0,
MovedCodeWrappedInNewNs);
addOrMergeReplacement(Deletion, &NewReplacements);
addOrMergeReplacement(Insertion, &NewReplacements);
}
// After moving namespaces, insert forward declarations back to old
// namespaces.
const auto &FwdDeclInsertions = InsertFwdDecls[FilePath];
for (const auto &FwdDeclInsertion : FwdDeclInsertions) {
unsigned NewInsertionOffset =
Replaces.getShiftedCodePosition(FwdDeclInsertion.InsertionOffset);
tooling::Replacement Insertion(FilePath, NewInsertionOffset, 0,
FwdDeclInsertion.ForwardDeclText);
addOrMergeReplacement(Insertion, &NewReplacements);
}
// Add replacements referring to the changed code to existing replacements,
// which refers to the original code.
Replaces = Replaces.merge(NewReplacements);
format::FormatStyle Style =
format::getStyle("file", FilePath, FallbackStyle);
// Clean up old namespaces if there is nothing in it after moving.
auto CleanReplacements =
format::cleanupAroundReplacements(Code, Replaces, Style);
if (!CleanReplacements) {
llvm::errs() << llvm::toString(CleanReplacements.takeError()) << "\n";
continue;
}
FileToReplacements[FilePath] = *CleanReplacements;
}
}
} // namespace change_namespace
} // namespace clang