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-rw-r--r--lib/Tooling/Refactoring/ASTSelection.cpp453
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diff --git a/lib/Tooling/Refactoring/ASTSelection.cpp b/lib/Tooling/Refactoring/ASTSelection.cpp
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+//===--- ASTSelection.cpp - Clang refactoring library ---------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Tooling/Refactoring/ASTSelection.h"
+#include "clang/AST/LexicallyOrderedRecursiveASTVisitor.h"
+#include "clang/Lex/Lexer.h"
+#include "llvm/Support/SaveAndRestore.h"
+
+using namespace clang;
+using namespace tooling;
+using ast_type_traits::DynTypedNode;
+
+namespace {
+
+CharSourceRange getLexicalDeclRange(Decl *D, const SourceManager &SM,
+ const LangOptions &LangOpts) {
+ if (!isa<ObjCImplDecl>(D))
+ return CharSourceRange::getTokenRange(D->getSourceRange());
+ // Objective-C implementation declarations end at the '@' instead of the 'end'
+ // keyword. Use the lexer to find the location right after 'end'.
+ SourceRange R = D->getSourceRange();
+ SourceLocation LocAfterEnd = Lexer::findLocationAfterToken(
+ R.getEnd(), tok::raw_identifier, SM, LangOpts,
+ /*SkipTrailingWhitespaceAndNewLine=*/false);
+ return LocAfterEnd.isValid()
+ ? CharSourceRange::getCharRange(R.getBegin(), LocAfterEnd)
+ : CharSourceRange::getTokenRange(R);
+}
+
+/// Constructs the tree of selected AST nodes that either contain the location
+/// of the cursor or overlap with the selection range.
+class ASTSelectionFinder
+ : public LexicallyOrderedRecursiveASTVisitor<ASTSelectionFinder> {
+public:
+ ASTSelectionFinder(SourceRange Selection, FileID TargetFile,
+ const ASTContext &Context)
+ : LexicallyOrderedRecursiveASTVisitor(Context.getSourceManager()),
+ SelectionBegin(Selection.getBegin()),
+ SelectionEnd(Selection.getBegin() == Selection.getEnd()
+ ? SourceLocation()
+ : Selection.getEnd()),
+ TargetFile(TargetFile), Context(Context) {
+ // The TU decl is the root of the selected node tree.
+ SelectionStack.push_back(
+ SelectedASTNode(DynTypedNode::create(*Context.getTranslationUnitDecl()),
+ SourceSelectionKind::None));
+ }
+
+ Optional<SelectedASTNode> getSelectedASTNode() {
+ assert(SelectionStack.size() == 1 && "stack was not popped");
+ SelectedASTNode Result = std::move(SelectionStack.back());
+ SelectionStack.pop_back();
+ if (Result.Children.empty())
+ return None;
+ return std::move(Result);
+ }
+
+ bool TraversePseudoObjectExpr(PseudoObjectExpr *E) {
+ // Avoid traversing the semantic expressions. They should be handled by
+ // looking through the appropriate opaque expressions in order to build
+ // a meaningful selection tree.
+ llvm::SaveAndRestore<bool> LookThrough(LookThroughOpaqueValueExprs, true);
+ return TraverseStmt(E->getSyntacticForm());
+ }
+
+ bool TraverseOpaqueValueExpr(OpaqueValueExpr *E) {
+ if (!LookThroughOpaqueValueExprs)
+ return true;
+ llvm::SaveAndRestore<bool> LookThrough(LookThroughOpaqueValueExprs, false);
+ return TraverseStmt(E->getSourceExpr());
+ }
+
+ bool TraverseDecl(Decl *D) {
+ if (isa<TranslationUnitDecl>(D))
+ return LexicallyOrderedRecursiveASTVisitor::TraverseDecl(D);
+ if (D->isImplicit())
+ return true;
+
+ // Check if this declaration is written in the file of interest.
+ const SourceRange DeclRange = D->getSourceRange();
+ const SourceManager &SM = Context.getSourceManager();
+ SourceLocation FileLoc;
+ if (DeclRange.getBegin().isMacroID() && !DeclRange.getEnd().isMacroID())
+ FileLoc = DeclRange.getEnd();
+ else
+ FileLoc = SM.getSpellingLoc(DeclRange.getBegin());
+ if (SM.getFileID(FileLoc) != TargetFile)
+ return true;
+
+ SourceSelectionKind SelectionKind =
+ selectionKindFor(getLexicalDeclRange(D, SM, Context.getLangOpts()));
+ SelectionStack.push_back(
+ SelectedASTNode(DynTypedNode::create(*D), SelectionKind));
+ LexicallyOrderedRecursiveASTVisitor::TraverseDecl(D);
+ popAndAddToSelectionIfSelected(SelectionKind);
+
+ if (DeclRange.getEnd().isValid() &&
+ SM.isBeforeInTranslationUnit(SelectionEnd.isValid() ? SelectionEnd
+ : SelectionBegin,
+ DeclRange.getEnd())) {
+ // Stop early when we've reached a declaration after the selection.
+ return false;
+ }
+ return true;
+ }
+
+ bool TraverseStmt(Stmt *S) {
+ if (!S)
+ return true;
+ if (auto *Opaque = dyn_cast<OpaqueValueExpr>(S))
+ return TraverseOpaqueValueExpr(Opaque);
+ // Avoid selecting implicit 'this' expressions.
+ if (auto *TE = dyn_cast<CXXThisExpr>(S)) {
+ if (TE->isImplicit())
+ return true;
+ }
+ // FIXME (Alex Lorenz): Improve handling for macro locations.
+ SourceSelectionKind SelectionKind =
+ selectionKindFor(CharSourceRange::getTokenRange(S->getSourceRange()));
+ SelectionStack.push_back(
+ SelectedASTNode(DynTypedNode::create(*S), SelectionKind));
+ LexicallyOrderedRecursiveASTVisitor::TraverseStmt(S);
+ popAndAddToSelectionIfSelected(SelectionKind);
+ return true;
+ }
+
+private:
+ void popAndAddToSelectionIfSelected(SourceSelectionKind SelectionKind) {
+ SelectedASTNode Node = std::move(SelectionStack.back());
+ SelectionStack.pop_back();
+ if (SelectionKind != SourceSelectionKind::None || !Node.Children.empty())
+ SelectionStack.back().Children.push_back(std::move(Node));
+ }
+
+ SourceSelectionKind selectionKindFor(CharSourceRange Range) {
+ SourceLocation End = Range.getEnd();
+ const SourceManager &SM = Context.getSourceManager();
+ if (Range.isTokenRange())
+ End = Lexer::getLocForEndOfToken(End, 0, SM, Context.getLangOpts());
+ if (!SourceLocation::isPairOfFileLocations(Range.getBegin(), End))
+ return SourceSelectionKind::None;
+ if (!SelectionEnd.isValid()) {
+ // Do a quick check when the selection is of length 0.
+ if (SM.isPointWithin(SelectionBegin, Range.getBegin(), End))
+ return SourceSelectionKind::ContainsSelection;
+ return SourceSelectionKind::None;
+ }
+ bool HasStart = SM.isPointWithin(SelectionBegin, Range.getBegin(), End);
+ bool HasEnd = SM.isPointWithin(SelectionEnd, Range.getBegin(), End);
+ if (HasStart && HasEnd)
+ return SourceSelectionKind::ContainsSelection;
+ if (SM.isPointWithin(Range.getBegin(), SelectionBegin, SelectionEnd) &&
+ SM.isPointWithin(End, SelectionBegin, SelectionEnd))
+ return SourceSelectionKind::InsideSelection;
+ // Ensure there's at least some overlap with the 'start'/'end' selection
+ // types.
+ if (HasStart && SelectionBegin != End)
+ return SourceSelectionKind::ContainsSelectionStart;
+ if (HasEnd && SelectionEnd != Range.getBegin())
+ return SourceSelectionKind::ContainsSelectionEnd;
+
+ return SourceSelectionKind::None;
+ }
+
+ const SourceLocation SelectionBegin, SelectionEnd;
+ FileID TargetFile;
+ const ASTContext &Context;
+ std::vector<SelectedASTNode> SelectionStack;
+ /// Controls whether we can traverse through the OpaqueValueExpr. This is
+ /// typically enabled during the traversal of syntactic form for
+ /// PseudoObjectExprs.
+ bool LookThroughOpaqueValueExprs = false;
+};
+
+} // end anonymous namespace
+
+Optional<SelectedASTNode>
+clang::tooling::findSelectedASTNodes(const ASTContext &Context,
+ SourceRange SelectionRange) {
+ assert(SelectionRange.isValid() &&
+ SourceLocation::isPairOfFileLocations(SelectionRange.getBegin(),
+ SelectionRange.getEnd()) &&
+ "Expected a file range");
+ FileID TargetFile =
+ Context.getSourceManager().getFileID(SelectionRange.getBegin());
+ assert(Context.getSourceManager().getFileID(SelectionRange.getEnd()) ==
+ TargetFile &&
+ "selection range must span one file");
+
+ ASTSelectionFinder Visitor(SelectionRange, TargetFile, Context);
+ Visitor.TraverseDecl(Context.getTranslationUnitDecl());
+ return Visitor.getSelectedASTNode();
+}
+
+static const char *selectionKindToString(SourceSelectionKind Kind) {
+ switch (Kind) {
+ case SourceSelectionKind::None:
+ return "none";
+ case SourceSelectionKind::ContainsSelection:
+ return "contains-selection";
+ case SourceSelectionKind::ContainsSelectionStart:
+ return "contains-selection-start";
+ case SourceSelectionKind::ContainsSelectionEnd:
+ return "contains-selection-end";
+ case SourceSelectionKind::InsideSelection:
+ return "inside";
+ }
+ llvm_unreachable("invalid selection kind");
+}
+
+static void dump(const SelectedASTNode &Node, llvm::raw_ostream &OS,
+ unsigned Indent = 0) {
+ OS.indent(Indent * 2);
+ if (const Decl *D = Node.Node.get<Decl>()) {
+ OS << D->getDeclKindName() << "Decl";
+ if (const auto *ND = dyn_cast<NamedDecl>(D))
+ OS << " \"" << ND->getNameAsString() << '"';
+ } else if (const Stmt *S = Node.Node.get<Stmt>()) {
+ OS << S->getStmtClassName();
+ }
+ OS << ' ' << selectionKindToString(Node.SelectionKind) << "\n";
+ for (const auto &Child : Node.Children)
+ dump(Child, OS, Indent + 1);
+}
+
+void SelectedASTNode::dump(llvm::raw_ostream &OS) const { ::dump(*this, OS); }
+
+/// Returns true if the given node has any direct children with the following
+/// selection kind.
+///
+/// Note: The direct children also include children of direct children with the
+/// "None" selection kind.
+static bool hasAnyDirectChildrenWithKind(const SelectedASTNode &Node,
+ SourceSelectionKind Kind) {
+ assert(Kind != SourceSelectionKind::None && "invalid predicate!");
+ for (const auto &Child : Node.Children) {
+ if (Child.SelectionKind == Kind)
+ return true;
+ if (Child.SelectionKind == SourceSelectionKind::None)
+ return hasAnyDirectChildrenWithKind(Child, Kind);
+ }
+ return false;
+}
+
+namespace {
+struct SelectedNodeWithParents {
+ SelectedNodeWithParents(SelectedNodeWithParents &&) = default;
+ SelectedNodeWithParents &operator=(SelectedNodeWithParents &&) = default;
+ SelectedASTNode::ReferenceType Node;
+ llvm::SmallVector<SelectedASTNode::ReferenceType, 8> Parents;
+
+ /// Canonicalizes the given selection by selecting different related AST nodes
+ /// when it makes sense to do so.
+ void canonicalize();
+};
+
+enum SelectionCanonicalizationAction { KeepSelection, SelectParent };
+
+/// Returns the canonicalization action which should be applied to the
+/// selected statement.
+SelectionCanonicalizationAction
+getSelectionCanonizalizationAction(const Stmt *S, const Stmt *Parent) {
+ // Select the parent expression when:
+ // - The string literal in ObjC string literal is selected, e.g.:
+ // @"test" becomes @"test"
+ // ~~~~~~ ~~~~~~~
+ if (isa<StringLiteral>(S) && isa<ObjCStringLiteral>(Parent))
+ return SelectParent;
+ // The entire call should be selected when just the member expression
+ // that refers to the method or the decl ref that refers to the function
+ // is selected.
+ // f.call(args) becomes f.call(args)
+ // ~~~~ ~~~~~~~~~~~~
+ // func(args) becomes func(args)
+ // ~~~~ ~~~~~~~~~~
+ else if (const auto *CE = dyn_cast<CallExpr>(Parent)) {
+ if ((isa<MemberExpr>(S) || isa<DeclRefExpr>(S)) &&
+ CE->getCallee()->IgnoreImpCasts() == S)
+ return SelectParent;
+ }
+ // FIXME: Syntactic form -> Entire pseudo-object expr.
+ return KeepSelection;
+}
+
+} // end anonymous namespace
+
+void SelectedNodeWithParents::canonicalize() {
+ const Stmt *S = Node.get().Node.get<Stmt>();
+ assert(S && "non statement selection!");
+ const Stmt *Parent = Parents[Parents.size() - 1].get().Node.get<Stmt>();
+ if (!Parent)
+ return;
+
+ // Look through the implicit casts in the parents.
+ unsigned ParentIndex = 1;
+ for (; (ParentIndex + 1) <= Parents.size() && isa<ImplicitCastExpr>(Parent);
+ ++ParentIndex) {
+ const Stmt *NewParent =
+ Parents[Parents.size() - ParentIndex - 1].get().Node.get<Stmt>();
+ if (!NewParent)
+ break;
+ Parent = NewParent;
+ }
+
+ switch (getSelectionCanonizalizationAction(S, Parent)) {
+ case SelectParent:
+ Node = Parents[Parents.size() - ParentIndex];
+ for (; ParentIndex != 0; --ParentIndex)
+ Parents.pop_back();
+ break;
+ case KeepSelection:
+ break;
+ }
+}
+
+/// Finds the set of bottom-most selected AST nodes that are in the selection
+/// tree with the specified selection kind.
+///
+/// For example, given the following selection tree:
+///
+/// FunctionDecl "f" contains-selection
+/// CompoundStmt contains-selection [#1]
+/// CallExpr inside
+/// ImplicitCastExpr inside
+/// DeclRefExpr inside
+/// IntegerLiteral inside
+/// IntegerLiteral inside
+/// FunctionDecl "f2" contains-selection
+/// CompoundStmt contains-selection [#2]
+/// CallExpr inside
+/// ImplicitCastExpr inside
+/// DeclRefExpr inside
+/// IntegerLiteral inside
+/// IntegerLiteral inside
+///
+/// This function will find references to nodes #1 and #2 when searching for the
+/// \c ContainsSelection kind.
+static void findDeepestWithKind(
+ const SelectedASTNode &ASTSelection,
+ llvm::SmallVectorImpl<SelectedNodeWithParents> &MatchingNodes,
+ SourceSelectionKind Kind,
+ llvm::SmallVectorImpl<SelectedASTNode::ReferenceType> &ParentStack) {
+ if (ASTSelection.Node.get<DeclStmt>()) {
+ // Select the entire decl stmt when any of its child declarations is the
+ // bottom-most.
+ for (const auto &Child : ASTSelection.Children) {
+ if (!hasAnyDirectChildrenWithKind(Child, Kind)) {
+ MatchingNodes.push_back(SelectedNodeWithParents{
+ std::cref(ASTSelection), {ParentStack.begin(), ParentStack.end()}});
+ return;
+ }
+ }
+ } else {
+ if (!hasAnyDirectChildrenWithKind(ASTSelection, Kind)) {
+ // This node is the bottom-most.
+ MatchingNodes.push_back(SelectedNodeWithParents{
+ std::cref(ASTSelection), {ParentStack.begin(), ParentStack.end()}});
+ return;
+ }
+ }
+ // Search in the children.
+ ParentStack.push_back(std::cref(ASTSelection));
+ for (const auto &Child : ASTSelection.Children)
+ findDeepestWithKind(Child, MatchingNodes, Kind, ParentStack);
+ ParentStack.pop_back();
+}
+
+static void findDeepestWithKind(
+ const SelectedASTNode &ASTSelection,
+ llvm::SmallVectorImpl<SelectedNodeWithParents> &MatchingNodes,
+ SourceSelectionKind Kind) {
+ llvm::SmallVector<SelectedASTNode::ReferenceType, 16> ParentStack;
+ findDeepestWithKind(ASTSelection, MatchingNodes, Kind, ParentStack);
+}
+
+Optional<CodeRangeASTSelection>
+CodeRangeASTSelection::create(SourceRange SelectionRange,
+ const SelectedASTNode &ASTSelection) {
+ // Code range is selected when the selection range is not empty.
+ if (SelectionRange.getBegin() == SelectionRange.getEnd())
+ return None;
+ llvm::SmallVector<SelectedNodeWithParents, 4> ContainSelection;
+ findDeepestWithKind(ASTSelection, ContainSelection,
+ SourceSelectionKind::ContainsSelection);
+ // We are looking for a selection in one body of code, so let's focus on
+ // one matching result.
+ if (ContainSelection.size() != 1)
+ return None;
+ SelectedNodeWithParents &Selected = ContainSelection[0];
+ if (!Selected.Node.get().Node.get<Stmt>())
+ return None;
+ const Stmt *CodeRangeStmt = Selected.Node.get().Node.get<Stmt>();
+ if (!isa<CompoundStmt>(CodeRangeStmt)) {
+ Selected.canonicalize();
+ return CodeRangeASTSelection(Selected.Node, Selected.Parents,
+ /*AreChildrenSelected=*/false);
+ }
+ // FIXME (Alex L): First selected SwitchCase means that first case statement.
+ // is selected actually
+ // (See https://github.com/apple/swift-clang & CompoundStmtRange).
+
+ // FIXME (Alex L): Tweak selection rules for compound statements, see:
+ // https://github.com/apple/swift-clang/blob/swift-4.1-branch/lib/Tooling/
+ // Refactor/ASTSlice.cpp#L513
+ // The user selected multiple statements in a compound statement.
+ Selected.Parents.push_back(Selected.Node);
+ return CodeRangeASTSelection(Selected.Node, Selected.Parents,
+ /*AreChildrenSelected=*/true);
+}
+
+static bool isFunctionLikeDeclaration(const Decl *D) {
+ // FIXME (Alex L): Test for BlockDecl.
+ return isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D);
+}
+
+bool CodeRangeASTSelection::isInFunctionLikeBodyOfCode() const {
+ bool IsPrevCompound = false;
+ // Scan through the parents (bottom-to-top) and check if the selection is
+ // contained in a compound statement that's a body of a function/method
+ // declaration.
+ for (const auto &Parent : llvm::reverse(Parents)) {
+ const DynTypedNode &Node = Parent.get().Node;
+ if (const auto *D = Node.get<Decl>()) {
+ if (isFunctionLikeDeclaration(D))
+ return IsPrevCompound;
+ // Stop the search at any type declaration to avoid returning true for
+ // expressions in type declarations in functions, like:
+ // function foo() { struct X {
+ // int m = /*selection:*/ 1 + 2 /*selection end*/; }; };
+ if (isa<TypeDecl>(D))
+ return false;
+ }
+ IsPrevCompound = Node.get<CompoundStmt>() != nullptr;
+ }
+ return false;
+}
+
+const Decl *CodeRangeASTSelection::getFunctionLikeNearestParent() const {
+ for (const auto &Parent : llvm::reverse(Parents)) {
+ const DynTypedNode &Node = Parent.get().Node;
+ if (const auto *D = Node.get<Decl>()) {
+ if (isFunctionLikeDeclaration(D))
+ return D;
+ }
+ }
+ return nullptr;
+}
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