blob: d07fd3629489d882da6b408fda54f9fc437f71f1 [file] [log] [blame]
// Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
library kernel.clone;
import 'ast.dart';
import 'type_algebra.dart';
typedef Member MemberSubstitutor(TreeNode receiver, Member m, Arguments arguments);
Member _noopMemberSubstitutor(TreeNode receiver, Member m, Arguments arguments) => m;
typedef DartType TypeSubstitutor(DartType m);
DartType _noopTypeSubstitutor(DartType t) => t;
/// Visitor that return a clone of a tree, maintaining references to cloned
/// objects.
///
/// It is safe to clone members, but cloning a class or library is not
/// supported.
class CloneVisitor extends TreeVisitor {
final Map<VariableDeclaration, VariableDeclaration> variables =
<VariableDeclaration, VariableDeclaration>{};
final Map<LabeledStatement, LabeledStatement> labels =
<LabeledStatement, LabeledStatement>{};
final Map<SwitchCase, SwitchCase> switchCases = <SwitchCase, SwitchCase>{};
final Map<TypeParameter, DartType> typeSubstitution;
final MemberSubstitutor memberSubstitutor;
final TypeSubstitutor typeSubstitutor;
CloneVisitor(
{Map<TypeParameter, DartType> typeSubstitution,
this.memberSubstitutor: _noopMemberSubstitutor,
this.typeSubstitutor: _noopTypeSubstitutor})
: this.typeSubstitution = ensureMutable(typeSubstitution);
static Map<TypeParameter, DartType> ensureMutable(
Map<TypeParameter, DartType> map) {
// We need to mutate this map, so make sure we don't use a constant map.
if (map == null || map.isEmpty) {
return <TypeParameter, DartType>{};
}
return map;
}
TreeNode defaultTreeNode(TreeNode node) =>
throw "Cloning of ${node.runtimeType} is not implemented";
TreeNode visitLibrary(Library node) =>
throw 'Cloning of libraries is not implemented';
TreeNode visitClass(Class node) =>
throw 'Clonning of classes is not implemented';
TreeNode clone(TreeNode node) =>
node.accept(this)..fileOffset = node.fileOffset;
TreeNode cloneOptional(TreeNode node) {
TreeNode result = node?.accept(this);
if (result != null) result.fileOffset = node.fileOffset;
return result;
}
DartType visitType(DartType type) =>
typeSubstitutor(substitute(type, typeSubstitution));
DartType visitOptionalType(DartType type) {
return type == null ? null : visitType(type);
}
visitInvalidExpression(InvalidExpression node) => new InvalidExpression();
visitVariableGet(VariableGet node) {
return new VariableGet(
variables[node.variable], visitOptionalType(node.promotedType));
}
visitVariableSet(VariableSet node) {
return new VariableSet(variables[node.variable], clone(node.value));
}
Member redirect(TreeNode receiver, Member m, Arguments arguments) =>
m == null ? null : memberSubstitutor(receiver, m, arguments);
visitPropertyGet(PropertyGet node) {
final receiver = clone(node.receiver);
return new PropertyGet(
receiver, node.name, redirect(receiver, node.interfaceTarget, null));
}
visitPropertySet(PropertySet node) {
final receiver = clone(node.receiver);
return new PropertySet(receiver, node.name, clone(node.value),
redirect(receiver, node.interfaceTarget, null));
}
visitDirectPropertyGet(DirectPropertyGet node) {
final receiver = clone(node.receiver);
return new DirectPropertyGet(receiver, redirect(receiver, node.target, null));
}
visitDirectPropertySet(DirectPropertySet node) {
final receiver = clone(node.receiver);
return new DirectPropertySet(
receiver, redirect(receiver, node.target, null), clone(node.value));
}
visitSuperPropertyGet(SuperPropertyGet node) {
return new SuperPropertyGet(node.name, redirect(null, node.interfaceTarget, null));
}
visitSuperPropertySet(SuperPropertySet node) {
return new SuperPropertySet(
node.name, clone(node.value), redirect(null, node.interfaceTarget, null));
}
visitStaticGet(StaticGet node) {
return new StaticGet(redirect(null, node.target, null));
}
visitStaticSet(StaticSet node) {
return new StaticSet(redirect(null, node.target, null), clone(node.value));
}
visitMethodInvocation(MethodInvocation node) {
final receiver = clone(node.receiver);
final arguments = clone(node.arguments);
return new MethodInvocation(receiver, node.name,
arguments, redirect(receiver, node.interfaceTarget, arguments));
}
visitDirectMethodInvocation(DirectMethodInvocation node) {
final receiver = clone(node.receiver);
final arguments = clone(node.arguments);
return new DirectMethodInvocation(
receiver, redirect(receiver, node.target, arguments), arguments);
}
visitSuperMethodInvocation(SuperMethodInvocation node) {
final arguments = clone(node.arguments);
return new SuperMethodInvocation(
node.name, arguments, redirect(null, node.interfaceTarget, clone(node.arguments)));
}
visitStaticInvocation(StaticInvocation node) {
final arguments = clone(node.arguments);
return new StaticInvocation(redirect(null, node.target, arguments), arguments,
isConst: node.isConst);
}
@override
visitConstructorInvocation(ConstructorInvocation node) {
return new ConstructorInvocation(
node.target, clone(node.arguments),
isConst: node.isConst);
}
visitFieldInitializer(FieldInitializer node) {
final receiver = clone(node.value);
return new FieldInitializer(redirect(receiver, node.field, null), receiver);
}
visitSuperInitializer(SuperInitializer node) {
return new SuperInitializer(
redirect(null, node.target, node.arguments), visitArguments(node.arguments));
}
visitNot(Not node) {
return new Not(clone(node.operand));
}
visitLogicalExpression(LogicalExpression node) {
return new LogicalExpression(
clone(node.left), node.operator, clone(node.right));
}
visitConditionalExpression(ConditionalExpression node) {
return new ConditionalExpression(clone(node.condition), clone(node.then),
clone(node.otherwise), visitOptionalType(node.staticType));
}
visitStringConcatenation(StringConcatenation node) {
return new StringConcatenation(node.expressions.map(clone).toList());
}
visitIsExpression(IsExpression node) {
return new IsExpression(clone(node.operand), visitType(node.type));
}
visitAsExpression(AsExpression node) {
return new AsExpression(clone(node.operand), visitType(node.type));
}
visitSymbolLiteral(SymbolLiteral node) {
return new SymbolLiteral(node.value);
}
visitTypeLiteral(TypeLiteral node) {
return new TypeLiteral(visitType(node.type));
}
visitThisExpression(ThisExpression node) {
return new ThisExpression();
}
visitRethrow(Rethrow node) {
return new Rethrow();
}
visitThrow(Throw node) {
return new Throw(cloneOptional(node.expression));
}
visitListLiteral(ListLiteral node) {
return new ListLiteral(node.expressions.map(clone).toList(),
typeArgument: visitType(node.typeArgument), isConst: node.isConst);
}
visitMapLiteral(MapLiteral node) {
return new MapLiteral(node.entries.map(clone).toList(),
keyType: visitType(node.keyType),
valueType: visitType(node.valueType),
isConst: node.isConst);
}
visitMapEntry(MapEntry node) {
return new MapEntry(clone(node.key), clone(node.value));
}
visitAwaitExpression(AwaitExpression node) {
return new AwaitExpression(clone(node.operand));
}
visitFunctionExpression(FunctionExpression node) {
return new FunctionExpression(clone(node.function));
}
visitStringLiteral(StringLiteral node) {
return new StringLiteral(node.value);
}
visitIntLiteral(IntLiteral node) {
return new IntLiteral(node.value);
}
visitDoubleLiteral(DoubleLiteral node) {
return new DoubleLiteral(node.value);
}
visitBoolLiteral(BoolLiteral node) {
return new BoolLiteral(node.value);
}
visitNullLiteral(NullLiteral node) {
return new NullLiteral();
}
visitLet(Let node) {
var newVariable = clone(node.variable);
return new Let(newVariable, clone(node.body));
}
visitVectorCreation(VectorCreation node) {
return new VectorCreation(node.length);
}
visitClosureCreation(ClosureCreation node) {
return new ClosureCreation.byReference(
node.topLevelFunctionReference,
cloneOptional(node.contextVector),
visitOptionalType(node.functionType),
node.typeArguments.map(visitType).toList());
}
visitVectorSet(VectorSet node) {
return new VectorSet(
clone(node.vectorExpression), node.index, clone(node.value));
}
visitVectorGet(VectorGet node) {
return new VectorGet(clone(node.vectorExpression), node.index);
}
visitVectorCopy(VectorCopy node) {
return new VectorCopy(clone(node.vectorExpression));
}
// Statements
visitInvalidStatement(InvalidStatement node) {
return new InvalidStatement();
}
visitExpressionStatement(ExpressionStatement node) {
return new ExpressionStatement(clone(node.expression));
}
visitBlock(Block node) {
return new Block(node.statements.map(clone).toList());
}
visitEmptyStatement(EmptyStatement node) {
return new EmptyStatement();
}
visitAssertStatement(AssertStatement node) {
return new AssertStatement(clone(node.condition),
conditionStartOffset: node.conditionStartOffset,
conditionEndOffset: node.conditionEndOffset,
message: cloneOptional(node.message));
}
visitLabeledStatement(LabeledStatement node) {
LabeledStatement newNode = new LabeledStatement(null);
labels[node] = newNode;
newNode.body = clone(node.body)..parent = newNode;
return newNode;
}
visitBreakStatement(BreakStatement node) {
return new BreakStatement(labels[node.target]);
}
visitWhileStatement(WhileStatement node) {
return new WhileStatement(clone(node.condition), clone(node.body));
}
visitDoStatement(DoStatement node) {
return new DoStatement(clone(node.body), clone(node.condition));
}
visitForStatement(ForStatement node) {
var variables = node.variables.map(clone).toList();
return new ForStatement(variables, cloneOptional(node.condition),
node.updates.map(clone).toList(), clone(node.body));
}
visitForInStatement(ForInStatement node) {
var newVariable = clone(node.variable);
return new ForInStatement(
newVariable, clone(node.iterable), clone(node.body));
}
visitSwitchStatement(SwitchStatement node) {
for (SwitchCase switchCase in node.cases) {
switchCases[switchCase] = new SwitchCase(
switchCase.expressions.map(clone).toList(),
new List<int>.from(switchCase.expressionOffsets),
null);
}
return new SwitchStatement(
clone(node.expression), node.cases.map(clone).toList());
}
visitSwitchCase(SwitchCase node) {
var switchCase = switchCases[node];
switchCase.body = clone(node.body)..parent = switchCase;
return switchCase;
}
visitContinueSwitchStatement(ContinueSwitchStatement node) {
return new ContinueSwitchStatement(switchCases[node.target]);
}
visitIfStatement(IfStatement node) {
return new IfStatement(
clone(node.condition), clone(node.then), cloneOptional(node.otherwise));
}
visitReturnStatement(ReturnStatement node) {
return new ReturnStatement(cloneOptional(node.expression));
}
visitTryCatch(TryCatch node) {
return new TryCatch(clone(node.body), node.catches.map(clone).toList());
}
visitCatch(Catch node) {
var newException = cloneOptional(node.exception);
var newStackTrace = cloneOptional(node.stackTrace);
return new Catch(newException, clone(node.body),
stackTrace: newStackTrace, guard: visitType(node.guard));
}
visitTryFinally(TryFinally node) {
return new TryFinally(clone(node.body), clone(node.finalizer));
}
visitYieldStatement(YieldStatement node) {
return new YieldStatement(clone(node.expression));
}
visitVariableDeclaration(VariableDeclaration node) {
return variables[node] = new VariableDeclaration(node.name,
initializer: cloneOptional(node.initializer),
type: visitType(node.type),
isCovariant: node.isCovariant,
isFinal: node.isFinal,
isConst: node.isConst,
isFieldFormal: node.isFieldFormal);
}
visitFunctionDeclaration(FunctionDeclaration node) {
var newVariable = clone(node.variable);
return new FunctionDeclaration(newVariable, clone(node.function));
}
// Members
visitConstructor(Constructor node) {
return new Constructor(clone(node.function),
name: node.name,
isConst: node.isConst,
isExternal: node.isExternal,
initializers: node.initializers.map(clone).toList(),
transformerFlags: node.transformerFlags)
..fileEndOffset = node.fileEndOffset;
}
visitProcedure(Procedure node) {
return new Procedure(node.name, node.kind, clone(node.function),
isAbstract: node.isAbstract,
isStatic: node.isStatic,
isExternal: node.isExternal,
isConst: node.isConst,
isForwardingStub: node.isForwardingStub,
transformerFlags: node.transformerFlags,
fileUri: node.fileUri)
..fileEndOffset = node.fileEndOffset;
}
visitField(Field node) {
return new Field(node.name,
type: visitType(node.type),
initializer: cloneOptional(node.initializer),
isCovariant: node.isCovariant,
isFinal: node.isFinal,
isConst: node.isConst,
isStatic: node.isStatic,
hasImplicitGetter: node.hasImplicitGetter,
hasImplicitSetter: node.hasImplicitSetter,
transformerFlags: node.transformerFlags,
fileUri: node.fileUri)
..fileEndOffset = node.fileEndOffset;
}
visitTypeParameter(TypeParameter node) {
if (typeSubstitution.containsKey(node)) {
return null;
}
var newNode = new TypeParameter(node.name);
typeSubstitution[node] = new TypeParameterType(newNode);
newNode.bound = visitType(node.bound);
return newNode;
}
TreeNode cloneFunctionNodeBody(FunctionNode node) => cloneOptional(node.body);
visitFunctionNode(FunctionNode node) {
var typeParameters = node.typeParameters.map(visitTypeParameter).where((node) => node != null).toList();
var positional = node.positionalParameters.map(clone).toList();
var named = node.namedParameters.map(clone).toList();
return new FunctionNode(cloneFunctionNodeBody(node),
typeParameters: typeParameters,
positionalParameters: positional,
namedParameters: named,
requiredParameterCount: node.requiredParameterCount,
returnType: visitType(node.returnType),
asyncMarker: node.asyncMarker,
dartAsyncMarker: node.dartAsyncMarker)
..fileEndOffset = node.fileEndOffset;
}
visitArguments(Arguments node) {
return new Arguments(node.positional.map(clone).toList(),
types: node.types.map(visitType).toList(),
named: node.named.map(clone).toList());
}
visitNamedExpression(NamedExpression node) {
return new NamedExpression(node.name, clone(node.value));
}
}