/**
* @param name The Name whose properties references should be updated.
* @param value The value to use when rewriting.
* @param depth The chain depth.
* @param newNodes Expression nodes that have been updated.
*/
private static void rewriteAliasProps(Name name, Node value, int depth, Set<AstChange> newNodes) {
if (name.props == null) {
return;
}
Preconditions.checkState(!value.matchesQualifiedName(name.getFullName()));
for (Name prop : name.props) {
rewriteAliasProps(prop, value, depth + 1, newNodes);
List<Ref> refs = new ArrayList<>(prop.getRefs());
for (Ref ref : refs) {
Node target = ref.node;
for (int i = 0; i <= depth; i++) {
if (target.isGetProp()) {
target = target.getFirstChild();
} else if (NodeUtil.isObjectLitKey(target)) {
// Object literal key definitions are a little trickier, as we
// need to find the assignment target
Node gparent = target.getParent().getParent();
if (gparent.isAssign()) {
target = gparent.getFirstChild();
} else {
Preconditions.checkState(NodeUtil.isObjectLitKey(gparent));
target = gparent;
}
} else {
throw new IllegalStateException("unexpected: " + target);
}
}
Preconditions.checkState(target.isGetProp() || target.isName());
target.getParent().replaceChild(target, value.cloneTree());
prop.removeRef(ref);
// Rescan the expression root.
newNodes.add(new AstChange(ref.module, ref.scope, ref.node));
}
}
}
static ClassDeclarationMetadata create(Node classNode, Node parent) {
Node classNameNode = classNode.getFirstChild();
Node superClassNameNode = classNameNode.getNext();
// If this is a class statement, or a class expression in a simple
// assignment or var statement, convert it. In any other case, the
// code is too dynamic, so return null.
if (NodeUtil.isStatement(classNode)) {
return new ClassDeclarationMetadata(
classNode, classNameNode.getString(), false, classNameNode, superClassNameNode);
} else if (parent.isAssign() && parent.getParent().isExprResult()) {
// Add members after the EXPR_RESULT node:
// example.C = class {}; example.C.prototype.foo = function() {};
String fullClassName = parent.getFirstChild().getQualifiedName();
if (fullClassName == null) {
return null;
}
return new ClassDeclarationMetadata(
parent.getParent(), fullClassName, true, classNameNode, superClassNameNode);
} else if (parent.isName()) {
// Add members after the 'var' statement.
// var C = class {}; C.prototype.foo = function() {};
return new ClassDeclarationMetadata(
parent.getParent(), parent.getString(), true, classNameNode, superClassNameNode);
} else {
// Cannot handle this class declaration.
return null;
}
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (!n.isAssign() || n.getFirstChild() == className) {
return;
}
if (className.matchesQualifiedName(n.getFirstChild())) {
compiler.report(JSError.make(n, CLASS_REASSIGNMENT));
}
}
/**
* Attempt to inline an global alias of a global name. This requires that the name is well
* defined: assigned unconditionally, assigned exactly once. It is assumed that, the name for
* which it is an alias must already meet these same requirements.
*
* @param alias The alias to inline
* @return Whether the alias was inlined.
*/
private boolean inlineGlobalAliasIfPossible(Name name, Ref alias, GlobalNamespace namespace) {
// Ensure that the alias is assigned to global name at that the
// declaration.
Node aliasParent = alias.node.getParent();
if (aliasParent.isAssign() && NodeUtil.isExecutedExactlyOnce(aliasParent)
// We special-case for constructors here, to inline constructor aliases
// more aggressively in global scope.
// We do this because constructor properties are always collapsed,
// so we want to inline the aliases also to avoid breakages.
|| aliasParent.isName() && name.isConstructor()) {
Node lvalue = aliasParent.isName() ? aliasParent : aliasParent.getFirstChild();
if (!lvalue.isQualifiedName()) {
return false;
}
name = namespace.getSlot(lvalue.getQualifiedName());
if (name != null && name.isInlinableGlobalAlias()) {
Set<AstChange> newNodes = new LinkedHashSet<>();
List<Ref> refs = new ArrayList<>(name.getRefs());
for (Ref ref : refs) {
switch (ref.type) {
case SET_FROM_GLOBAL:
continue;
case DIRECT_GET:
case ALIASING_GET:
Node newNode = alias.node.cloneTree();
Node node = ref.node;
node.getParent().replaceChild(node, newNode);
newNodes.add(new AstChange(ref.module, ref.scope, newNode));
name.removeRef(ref);
break;
default:
throw new IllegalStateException();
}
}
rewriteAliasProps(name, alias.node, 0, newNodes);
// just set the original alias to null.
aliasParent.replaceChild(alias.node, IR.nullNode());
compiler.reportCodeChange();
// Inlining the variable may have introduced new references
// to descendants of {@code name}. So those need to be collected now.
namespace.scanNewNodes(newNodes);
return true;
}
}
return false;
}
private void maybeReplaceJqueryPrototypeAlias(Node n) {
// Check to see if this is the assignment of the original alias.
// If so, leave it intact.
if (NodeUtil.isLValue(n)) {
Node maybeAssign = n.getParent();
while (!NodeUtil.isStatement(maybeAssign) && !maybeAssign.isAssign()) {
maybeAssign = maybeAssign.getParent();
}
if (maybeAssign.isAssign()) {
maybeAssign = maybeAssign.getParent();
if (maybeAssign.isBlock() || maybeAssign.isScript() || NodeUtil.isStatement(maybeAssign)) {
return;
}
}
}
Node fn = n.getLastChild();
if (fn != null) {
n.replaceChild(fn, IR.string("prototype").srcref(fn));
compiler.reportCodeChange();
}
}
private void rewriteClassDefinition(Node n, Node parent, NodeTraversal t) {
if (parent.getParent().isConst() || parent.getParent().isLet()) {
compiler.report(JSError.make(n, POLYMER_INVALID_DECLARATION));
return;
}
ClassDefinition def = extractClassDefinition(n);
if (def != null) {
if (NodeUtil.isNameDeclaration(parent.getParent()) || parent.isAssign()) {
rewritePolymerClass(parent.getParent(), def, t);
} else {
rewritePolymerClass(parent, def, t);
}
}
}
@Override
public CheckLevel level(JSError error) {
Node node = error.node;
if (node != null) {
boolean visitedFunction = false;
for (Node current = node; current != null; current = current.getParent()) {
Token type = current.getToken();
JSDocInfo info = null;
if (type == Token.FUNCTION) {
info = NodeUtil.getBestJSDocInfo(current);
visitedFunction = true;
} else if (type == Token.SCRIPT) {
info = current.getJSDocInfo();
} else if (current.isVar() || current.isAssign()) {
// There's one edge case we're worried about:
// if the warning points to an assignment to a function, we
// want the suppressions on that function to apply.
// It's OK if we double-count some cases.
Node rhs = NodeUtil.getRValueOfLValue(current.getFirstChild());
if (rhs != null) {
if (rhs.isCast()) {
rhs = rhs.getFirstChild();
}
if (rhs.isFunction() && !visitedFunction) {
info = NodeUtil.getBestJSDocInfo(current);
}
}
}
if (info != null) {
for (String suppressor : info.getSuppressions()) {
WarningsGuard guard = suppressors.get(suppressor);
// Some @suppress tags are for other tools, and
// may not have a warnings guard.
if (guard != null) {
CheckLevel newLevel = guard.level(error);
if (newLevel != null) {
return newLevel;
}
}
}
}
}
}
return null;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (n.isFunction()) {
checkFunctionUse(t, n);
} else if (n.isAssign()) {
checkAssignment(t, n);
} else if (n.isDelProp()) {
checkDelete(t, n);
} else if (n.isObjectLit()) {
checkObjectLiteralOrClass(t, n);
} else if (n.isClass()) {
checkObjectLiteralOrClass(t, n.getLastChild());
} else if (n.isWith()) {
checkWith(t, n);
}
}
/**
* If this returns true, check for @extends and @implements annotations on this node. Otherwise,
* it's probably an alias for an existing class, so skip those annotations.
*
* @return Whether the given node declares a function. True for the following forms:
* <li>
* <pre>function foo() {}</pre>
* <li>
* <pre>var foo = function() {};</pre>
* <li>
* <pre>foo.bar = function() {};</pre>
*/
private boolean declaresFunction(Node n) {
if (n.isFunction()) {
return true;
}
if (n.isAssign() && n.getLastChild().isFunction()) {
return true;
}
if (NodeUtil.isNameDeclaration(n)
&& n.getFirstChild().hasChildren()
&& n.getFirstFirstChild().isFunction()) {
return true;
}
return false;
}
/**
* Returns whether the node is the right hand side of an assignment or initialization of a
* variable named *_ID of *_ID_.
*/
private boolean insideAssignmentToIdConstant(Node n) {
Node parent = n.getParent();
if (parent.isAssign()) {
String qname = parent.getFirstChild().getQualifiedName();
return qname != null && isIdName(qname);
} else if (parent.isName()) {
Node grandParent = parent.getParent();
if (grandParent != null && NodeUtil.isNameDeclaration(grandParent)) {
String name = parent.getString();
return isIdName(name);
} else {
return false;
}
} else {
return false;
}
}
/** Find functions that can be inlined. */
private void checkNameUsage(Node n, Node parent) {
Preconditions.checkState(n.isName());
if (isCandidateUsage(n)) {
return;
}
// Other refs to a function name remove its candidacy for inlining
String name = n.getString();
FunctionState fs = fns.get(name);
if (fs == null) {
return;
}
// Unlike normal call/new parameters, references passed to
// JSCompiler_ObjectPropertyString are not aliases of a value, but
// a reference to the name itself, as such the value of the name is
// unknown and can not be inlined.
if (parent.isNew()) {
Node target = parent.getFirstChild();
if (target.isName()
&& target
.getString()
.equals(ObjectPropertyStringPreprocess.EXTERN_OBJECT_PROPERTY_STRING)) {
// This method is going to be replaced so don't inline it anywhere.
fs.setInline(false);
}
}
// If the name is being assigned to it can not be inlined.
if (parent.isAssign() && parent.getFirstChild() == n) {
// e.g. bar = something; <== we can't inline "bar"
// so mark the function as uninlinable.
// TODO(johnlenz): Should we just remove it from fns here?
fs.setInline(false);
} else {
// e.g. var fn = bar; <== we can't inline "bar"
// As this reference can't be inlined mark the function as
// unremovable.
fs.setRemove(false);
}
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (isBehavior(n)) {
if (!n.isVar() && !n.isAssign()) {
compiler.report(JSError.make(n, POLYMER_UNQUALIFIED_BEHAVIOR));
return;
}
// Add @nocollapse.
JSDocInfoBuilder newDocs = JSDocInfoBuilder.maybeCopyFrom(n.getJSDocInfo());
newDocs.recordNoCollapse();
n.setJSDocInfo(newDocs.build());
Node behaviorValue = n.getChildAtIndex(1);
if (n.isVar()) {
behaviorValue = n.getFirstChild().getFirstChild();
}
suppressBehavior(behaviorValue);
}
}
private void visitCallNode(NodeTraversal t, Node call, Node parent) {
String required = codingConvention.extractClassNameIfRequire(call, parent);
if (required != null) {
visitRequire(required, call);
return;
}
String provided = codingConvention.extractClassNameIfProvide(call, parent);
if (provided != null) {
providedNames.add(provided);
return;
}
if (codingConvention.isClassFactoryCall(call)) {
if (parent.isName()) {
providedNames.add(parent.getString());
} else if (parent.isAssign()) {
providedNames.add(parent.getFirstChild().getQualifiedName());
}
}
Node callee = call.getFirstChild();
if (callee.isName()) {
weakUsages.put(callee.getString(), callee);
} else if (callee.isQualifiedName()) {
Node root = NodeUtil.getRootOfQualifiedName(callee);
if (root.isName()) {
Var var = t.getScope().getVar(root.getString());
if (var == null || (!var.isExtern() && !var.isLocal())) {
String name = getOutermostClassName(callee.getQualifiedName());
if (name == null) {
name = callee.getQualifiedName();
}
usages.put(name, call);
}
}
}
}
private void visitScriptNode(NodeTraversal t) {
if (mode == Mode.SINGLE_FILE && requires.isEmpty()) {
// Likely a file that isn't using Closure at all.
return;
}
Set<String> namespaces = new HashSet<>();
// For every usage, check that there is a goog.require, and warn if not.
for (Map.Entry<String, Node> entry : usages.entrySet()) {
String namespace = entry.getKey();
if (namespace.endsWith(".call") || namespace.endsWith(".apply")) {
namespace = namespace.substring(0, namespace.lastIndexOf('.'));
}
if (namespace.startsWith("goog.global.")) {
continue;
}
Node node = entry.getValue();
JSDocInfo info = NodeUtil.getBestJSDocInfo(NodeUtil.getEnclosingStatement(node));
if (info != null && info.getSuppressions().contains("missingRequire")) {
continue;
}
String outermostClassName = getOutermostClassName(namespace);
// The parent namespace is also checked as part of the requires so that classes
// used by goog.module are still checked properly. This may cause missing requires
// to be missed but in practice that should happen rarely.
String nonNullClassName = outermostClassName != null ? outermostClassName : namespace;
String parentNamespace = null;
int separatorIndex = nonNullClassName.lastIndexOf('.');
if (separatorIndex > 0) {
parentNamespace = nonNullClassName.substring(0, separatorIndex);
}
boolean notProvidedByConstructors =
!providedNames.contains(namespace)
&& !providedNames.contains(outermostClassName)
&& !providedNames.contains(parentNamespace);
boolean notProvidedByRequires =
!requires.containsKey(namespace)
&& !requires.containsKey(outermostClassName)
&& !requires.containsKey(parentNamespace);
if (notProvidedByConstructors
&& notProvidedByRequires
&& !namespaces.contains(namespace)
&& !"goog".equals(parentNamespace)) {
// TODO(mknichel): If the symbol is not explicitly provided, find the next best
// symbol from the provides in the same file.
String rootName = Splitter.on('.').split(namespace).iterator().next();
if (mode != Mode.SINGLE_FILE || closurizedNamespaces.contains(rootName)) {
if (node.isCall()) {
compiler.report(t.makeError(node, MISSING_REQUIRE_CALL_WARNING, namespace));
} else {
compiler.report(t.makeError(node, MISSING_REQUIRE_WARNING, namespace));
}
namespaces.add(namespace);
}
}
}
// For every goog.require, check that there is a usage (in either usages or weakUsages)
// and warn if there is not.
for (Map.Entry<String, Node> entry : requires.entrySet()) {
String require = entry.getKey();
Node call = entry.getValue();
Node parent = call.getParent();
if (parent.isAssign()) {
// var baz = goog.require('foo.bar.baz');
// Assume that the var 'baz' is used somewhere, and don't warn.
continue;
}
if (!usages.containsKey(require) && !weakUsages.containsKey(require)) {
reportExtraRequireWarning(call, require);
}
}
}
/**
* Classes are processed in 3 phases: 1) The class name is extracted. 2) Class members are
* processed and rewritten. 3) The constructor is built.
*/
private void visitClass(Node classNode, Node parent) {
checkClassReassignment(classNode);
// Collect Metadata
Node className = classNode.getFirstChild();
Node superClassName = className.getNext();
Node classMembers = classNode.getLastChild();
// This is a statement node. We insert methods of the
// transpiled class after this node.
Node insertionPoint;
if (!superClassName.isEmpty() && !superClassName.isQualifiedName()) {
compiler.report(JSError.make(superClassName, DYNAMIC_EXTENDS_TYPE));
return;
}
// The fully qualified name of the class, which will be used in the output.
// May come from the class itself or the LHS of an assignment.
String fullClassName = null;
// Whether the constructor function in the output should be anonymous.
boolean anonymous;
// If this is a class statement, or a class expression in a simple
// assignment or var statement, convert it. In any other case, the
// code is too dynamic, so just call cannotConvert.
if (NodeUtil.isStatement(classNode)) {
fullClassName = className.getString();
anonymous = false;
insertionPoint = classNode;
} else if (parent.isAssign() && parent.getParent().isExprResult()) {
// Add members after the EXPR_RESULT node:
// example.C = class {}; example.C.prototype.foo = function() {};
fullClassName = parent.getFirstChild().getQualifiedName();
if (fullClassName == null) {
cannotConvert(
parent,
"Can only convert classes that are declarations or the right hand"
+ " side of a simple assignment.");
return;
}
anonymous = true;
insertionPoint = parent.getParent();
} else if (parent.isName()) {
// Add members after the 'var' statement.
// var C = class {}; C.prototype.foo = function() {};
fullClassName = parent.getString();
anonymous = true;
insertionPoint = parent.getParent();
} else {
cannotConvert(
parent,
"Can only convert classes that are declarations or the right hand"
+ " side of a simple assignment.");
return;
}
if (!className.isEmpty() && !className.getString().equals(fullClassName)) {
// cannot bind two class names in the case of: var Foo = class Bar {};
cannotConvertYet(classNode, "named class in an assignment");
return;
}
boolean useUnique = NodeUtil.isStatement(classNode) && !isInFunction(classNode);
String uniqueFullClassName = useUnique ? getUniqueClassName(fullClassName) : fullClassName;
String superClassString = superClassName.getQualifiedName();
Verify.verify(NodeUtil.isStatement(insertionPoint));
Node constructor = null;
JSDocInfo ctorJSDocInfo = null;
// Process all members of the class
for (Node member : classMembers.children()) {
if (member.isEmpty()) {
continue;
}
if (member.isMemberDef() && member.getString().equals("constructor")) {
ctorJSDocInfo = member.getJSDocInfo();
constructor = member.getFirstChild().detachFromParent();
if (!anonymous) {
constructor.replaceChild(constructor.getFirstChild(), className.cloneNode());
}
} else {
Node qualifiedMemberName;
Node method;
if (member.isMemberDef()) {
if (member.isStaticMember()) {
qualifiedMemberName =
NodeUtil.newQualifiedNameNode(
compiler.getCodingConvention(),
Joiner.on(".").join(uniqueFullClassName, member.getString()));
} else {
qualifiedMemberName =
NodeUtil.newQualifiedNameNode(
compiler.getCodingConvention(),
Joiner.on(".").join(uniqueFullClassName, "prototype", member.getString()));
}
method = member.getFirstChild().detachFromParent();
} else if (member.isComputedProp()) {
if (member.isStaticMember()) {
qualifiedMemberName =
IR.getelem(
NodeUtil.newQualifiedNameNode(
compiler.getCodingConvention(), uniqueFullClassName),
member.removeFirstChild());
} else {
qualifiedMemberName =
IR.getelem(
NodeUtil.newQualifiedNameNode(
compiler.getCodingConvention(),
Joiner.on('.').join(uniqueFullClassName, "prototype")),
member.removeFirstChild());
}
method = member.getLastChild().detachFromParent();
} else {
throw new IllegalStateException("Unexpected class member: " + member);
}
Node assign = IR.assign(qualifiedMemberName, method);
assign.useSourceInfoIfMissingFromForTree(member);
JSDocInfo info = member.getJSDocInfo();
if (member.isStaticMember() && NodeUtil.referencesThis(assign.getLastChild())) {
JSDocInfoBuilder memberDoc;
if (info == null) {
memberDoc = new JSDocInfoBuilder(true);
} else {
memberDoc = JSDocInfoBuilder.copyFrom(info);
}
memberDoc.recordThisType(
new JSTypeExpression(
new Node(Token.BANG, new Node(Token.QMARK)), member.getSourceFileName()));
info = memberDoc.build(assign);
}
if (info != null) {
info.setAssociatedNode(assign);
assign.setJSDocInfo(info);
}
Node newNode = NodeUtil.newExpr(assign);
insertionPoint.getParent().addChildAfter(newNode, insertionPoint);
insertionPoint = newNode;
}
}
// Rewrite constructor
if (constructor == null) {
Node body = IR.block();
if (!superClassName.isEmpty()) {
Node superCall = baseCall(classNode, "constructor", null);
body.addChildToBack(IR.exprResult(superCall));
}
Node name = anonymous ? IR.name("").srcref(className) : className.detachFromParent();
constructor =
IR.function(name, IR.paramList(), body).useSourceInfoIfMissingFromForTree(classNode);
}
JSDocInfo classJSDoc = classNode.getJSDocInfo();
JSDocInfoBuilder newInfo =
(classJSDoc != null) ? JSDocInfoBuilder.copyFrom(classJSDoc) : new JSDocInfoBuilder(true);
newInfo.recordConstructor();
if (!superClassName.isEmpty()) {
if (newInfo.isInterfaceRecorded()) {
newInfo.recordExtendedInterface(
new JSTypeExpression(
new Node(Token.BANG, IR.string(superClassString)),
superClassName.getSourceFileName()));
} else {
Node inherits =
IR.call(
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), INHERITS),
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), fullClassName),
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), superClassString));
Node inheritsCall = IR.exprResult(inherits);
inheritsCall.useSourceInfoIfMissingFromForTree(classNode);
Node enclosingStatement = NodeUtil.getEnclosingStatement(classNode);
enclosingStatement.getParent().addChildAfter(inheritsCall, enclosingStatement);
newInfo.recordBaseType(
new JSTypeExpression(
new Node(Token.BANG, IR.string(superClassString)),
superClassName.getSourceFileName()));
Node copyProps =
IR.call(
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), COPY_PROP),
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), fullClassName),
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), superClassString));
copyProps.useSourceInfoIfMissingFromForTree(classNode);
enclosingStatement
.getParent()
.addChildAfter(IR.exprResult(copyProps).srcref(classNode), enclosingStatement);
}
}
// Classes are @struct by default.
if (!newInfo.isUnrestrictedRecorded()
&& !newInfo.isDictRecorded()
&& !newInfo.isStructRecorded()) {
newInfo.recordStruct();
}
if (ctorJSDocInfo != null) {
newInfo.recordSuppressions(ctorJSDocInfo.getSuppressions());
for (String param : ctorJSDocInfo.getParameterNames()) {
newInfo.recordParameter(param, ctorJSDocInfo.getParameterType(param));
}
}
insertionPoint = constructor;
if (NodeUtil.isStatement(classNode)) {
constructor.getFirstChild().setString("");
Node ctorVar = IR.var(IR.name(fullClassName), constructor);
ctorVar.useSourceInfoIfMissingFromForTree(classNode);
parent.replaceChild(classNode, ctorVar);
} else {
parent.replaceChild(classNode, constructor);
}
if (NodeUtil.isStatement(constructor)) {
insertionPoint.setJSDocInfo(newInfo.build(insertionPoint));
} else if (parent.isName()) {
// The constructor function is the RHS of a var statement.
// Add the JSDoc to the VAR node.
Node var = parent.getParent();
var.setJSDocInfo(newInfo.build(var));
} else if (constructor.getParent().isName()) {
// Is a newly created VAR node.
Node var = constructor.getParent().getParent();
var.setJSDocInfo(newInfo.build(var));
} else if (parent.isAssign()) {
// The constructor function is the RHS of an assignment.
// Add the JSDoc to the ASSIGN node.
parent.setJSDocInfo(newInfo.build(parent));
} else {
throw new IllegalStateException("Unexpected parent node " + parent);
}
compiler.reportCodeChange();
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
JSDocInfo docInfo = n.getJSDocInfo();
if (docInfo != null && docInfo.isExport()) {
if (parent.isAssign() && (n.isFunction() || n.isClass())) {
JSDocInfo parentInfo = parent.getJSDocInfo();
if (parentInfo != null && parentInfo.isExport()) {
// ScopedAliases produces export annotations on both the function/class
// node and assign node, we only want to visit the assign node.
return;
}
}
String export = null;
GenerateNodeContext context = null;
switch (n.getType()) {
case Token.FUNCTION:
case Token.CLASS:
if (parent.isScript()) {
export = NodeUtil.getName(n);
context = new GenerateNodeContext(n, Mode.EXPORT);
}
break;
case Token.MEMBER_FUNCTION_DEF:
export = n.getString();
context = new GenerateNodeContext(n, Mode.EXPORT);
break;
case Token.ASSIGN:
Node grandparent = parent.getParent();
if (parent.isExprResult() && !n.getLastChild().isAssign()) {
if (grandparent != null
&& grandparent.isScript()
&& n.getFirstChild().isQualifiedName()) {
export = n.getFirstChild().getQualifiedName();
context = new GenerateNodeContext(n, Mode.EXPORT);
} else if (allowLocalExports && n.getFirstChild().isGetProp()) {
Node target = n.getFirstChild();
export = target.getLastChild().getString();
context = new GenerateNodeContext(n, Mode.EXTERN);
}
}
break;
case Token.VAR:
case Token.LET:
case Token.CONST:
if (parent.isScript()) {
if (n.getFirstChild().hasChildren() && !n.getFirstChild().getFirstChild().isAssign()) {
export = n.getFirstChild().getString();
context = new GenerateNodeContext(n, Mode.EXPORT);
}
}
break;
case Token.GETPROP:
if (allowLocalExports && parent.isExprResult()) {
export = n.getLastChild().getString();
context = new GenerateNodeContext(n, Mode.EXTERN);
}
break;
case Token.STRING_KEY:
case Token.GETTER_DEF:
case Token.SETTER_DEF:
if (allowLocalExports) {
export = n.getString();
context = new GenerateNodeContext(n, Mode.EXTERN);
}
break;
}
if (export != null) {
exports.put(export, context);
} else {
// Don't produce extra warnings for functions values of object literals
if (!n.isFunction() || !NodeUtil.isObjectLitKey(parent)) {
if (allowLocalExports) {
compiler.report(t.makeError(n, EXPORT_ANNOTATION_NOT_ALLOWED));
} else {
compiler.report(t.makeError(n, NON_GLOBAL_ERROR));
}
}
}
}
}
/**
* Classes are processed in 3 phases:
*
* <ol>
* <li>The class name is extracted.
* <li>Class members are processed and rewritten.
* <li>The constructor is built.
* </ol>
*/
private void visitClass(Node classNode, Node parent) {
checkClassReassignment(classNode);
// Collect Metadata
ClassDeclarationMetadata metadata = ClassDeclarationMetadata.create(classNode, parent);
if (metadata == null || metadata.fullClassName == null) {
cannotConvert(
parent,
"Can only convert classes that are declarations or the right hand"
+ " side of a simple assignment.");
return;
}
if (metadata.hasSuperClass() && !metadata.superClassNameNode.isQualifiedName()) {
compiler.report(JSError.make(metadata.superClassNameNode, DYNAMIC_EXTENDS_TYPE));
return;
}
boolean useUnique = NodeUtil.isStatement(classNode) && !NodeUtil.isInFunction(classNode);
String uniqueFullClassName =
useUnique ? getUniqueClassName(metadata.fullClassName) : metadata.fullClassName;
Node classNameAccess = NodeUtil.newQName(compiler, uniqueFullClassName);
Node prototypeAccess = NodeUtil.newPropertyAccess(compiler, classNameAccess, "prototype");
Preconditions.checkState(
NodeUtil.isStatement(metadata.insertionPoint),
"insertion point must be a statement: %s",
metadata.insertionPoint);
Node constructor = null;
JSDocInfo ctorJSDocInfo = null;
// Process all members of the class
Node classMembers = classNode.getLastChild();
Map<String, JSDocInfo> prototypeMembersToDeclare = new LinkedHashMap<>();
Map<String, JSDocInfo> classMembersToDeclare = new LinkedHashMap<>();
for (Node member : classMembers.children()) {
if (member.isEmpty()) {
continue;
}
Preconditions.checkState(
member.isMemberFunctionDef()
|| member.isGetterDef()
|| member.isSetterDef()
|| (member.isComputedProp() && !member.getBooleanProp(Node.COMPUTED_PROP_VARIABLE)),
"Member variables should have been transpiled earlier: ",
member);
if (member.isGetterDef() || member.isSetterDef()) {
JSTypeExpression typeExpr = getTypeFromGetterOrSetter(member).clone();
addToDefinePropertiesObject(metadata, member);
Map<String, JSDocInfo> membersToDeclare =
member.isStaticMember() ? classMembersToDeclare : prototypeMembersToDeclare;
JSDocInfo existingJSDoc = membersToDeclare.get(member.getString());
JSTypeExpression existingType = existingJSDoc == null ? null : existingJSDoc.getType();
if (existingType != null && !existingType.equals(typeExpr)) {
compiler.report(JSError.make(member, CONFLICTING_GETTER_SETTER_TYPE, member.getString()));
} else {
JSDocInfoBuilder jsDoc = new JSDocInfoBuilder(false);
jsDoc.recordType(typeExpr);
if (member.getJSDocInfo() != null && member.getJSDocInfo().isExport()) {
jsDoc.recordExport();
}
if (member.isStaticMember()) {
jsDoc.recordNoCollapse();
}
membersToDeclare.put(member.getString(), jsDoc.build());
}
} else if (member.isMemberFunctionDef() && member.getString().equals("constructor")) {
ctorJSDocInfo = member.getJSDocInfo();
constructor = member.getFirstChild().detachFromParent();
if (!metadata.anonymous) {
// Turns class Foo { constructor: function() {} } into function Foo() {},
// i.e. attaches the name the ctor function.
constructor.replaceChild(constructor.getFirstChild(), metadata.classNameNode.cloneNode());
}
} else {
Node qualifiedMemberAccess =
getQualifiedMemberAccess(compiler, member, classNameAccess, prototypeAccess);
Node method = member.getLastChild().detachFromParent();
Node assign = IR.assign(qualifiedMemberAccess, method);
assign.useSourceInfoIfMissingFromForTree(member);
JSDocInfo info = member.getJSDocInfo();
if (member.isStaticMember() && NodeUtil.referencesThis(assign.getLastChild())) {
JSDocInfoBuilder memberDoc = JSDocInfoBuilder.maybeCopyFrom(info);
memberDoc.recordThisType(
new JSTypeExpression(
new Node(Token.BANG, new Node(Token.QMARK)), member.getSourceFileName()));
info = memberDoc.build();
}
if (info != null) {
assign.setJSDocInfo(info);
}
Node newNode = NodeUtil.newExpr(assign);
metadata.insertNodeAndAdvance(newNode);
}
}
// Add declarations for properties that were defined with a getter and/or setter,
// so that the typechecker knows those properties exist on the class.
// This is a temporary solution. Eventually, the type checker should understand
// Object.defineProperties calls directly.
for (Map.Entry<String, JSDocInfo> entry : prototypeMembersToDeclare.entrySet()) {
String declaredMember = entry.getKey();
Node declaration = IR.getprop(prototypeAccess.cloneTree(), IR.string(declaredMember));
declaration.setJSDocInfo(entry.getValue());
metadata.insertNodeAndAdvance(
IR.exprResult(declaration).useSourceInfoIfMissingFromForTree(classNode));
}
for (Map.Entry<String, JSDocInfo> entry : classMembersToDeclare.entrySet()) {
String declaredMember = entry.getKey();
Node declaration = IR.getprop(classNameAccess.cloneTree(), IR.string(declaredMember));
declaration.setJSDocInfo(entry.getValue());
metadata.insertNodeAndAdvance(
IR.exprResult(declaration).useSourceInfoIfMissingFromForTree(classNode));
}
if (metadata.definePropertiesObjForPrototype.hasChildren()) {
Node definePropsCall =
IR.exprResult(
IR.call(
NodeUtil.newQName(compiler, "Object.defineProperties"),
prototypeAccess.cloneTree(),
metadata.definePropertiesObjForPrototype));
definePropsCall.useSourceInfoIfMissingFromForTree(classNode);
metadata.insertNodeAndAdvance(definePropsCall);
}
if (metadata.definePropertiesObjForClass.hasChildren()) {
Node definePropsCall =
IR.exprResult(
IR.call(
NodeUtil.newQName(compiler, "Object.defineProperties"),
classNameAccess.cloneTree(),
metadata.definePropertiesObjForClass));
definePropsCall.useSourceInfoIfMissingFromForTree(classNode);
metadata.insertNodeAndAdvance(definePropsCall);
}
Preconditions.checkNotNull(constructor);
JSDocInfo classJSDoc = NodeUtil.getBestJSDocInfo(classNode);
JSDocInfoBuilder newInfo = JSDocInfoBuilder.maybeCopyFrom(classJSDoc);
newInfo.recordConstructor();
if (metadata.hasSuperClass()) {
String superClassString = metadata.superClassNameNode.getQualifiedName();
if (newInfo.isInterfaceRecorded()) {
newInfo.recordExtendedInterface(
new JSTypeExpression(
new Node(Token.BANG, IR.string(superClassString)),
metadata.superClassNameNode.getSourceFileName()));
} else {
Node inherits =
IR.call(
NodeUtil.newQName(compiler, INHERITS),
NodeUtil.newQName(compiler, metadata.fullClassName),
NodeUtil.newQName(compiler, superClassString));
Node inheritsCall = IR.exprResult(inherits);
compiler.needsEs6Runtime = true;
inheritsCall.useSourceInfoIfMissingFromForTree(classNode);
Node enclosingStatement = NodeUtil.getEnclosingStatement(classNode);
enclosingStatement.getParent().addChildAfter(inheritsCall, enclosingStatement);
newInfo.recordBaseType(
new JSTypeExpression(
new Node(Token.BANG, IR.string(superClassString)),
metadata.superClassNameNode.getSourceFileName()));
}
}
// Classes are @struct by default.
if (!newInfo.isUnrestrictedRecorded()
&& !newInfo.isDictRecorded()
&& !newInfo.isStructRecorded()) {
newInfo.recordStruct();
}
if (ctorJSDocInfo != null) {
newInfo.recordSuppressions(ctorJSDocInfo.getSuppressions());
for (String param : ctorJSDocInfo.getParameterNames()) {
newInfo.recordParameter(param, ctorJSDocInfo.getParameterType(param));
}
newInfo.mergePropertyBitfieldFrom(ctorJSDocInfo);
}
if (NodeUtil.isStatement(classNode)) {
constructor.getFirstChild().setString("");
Node ctorVar = IR.let(metadata.classNameNode.cloneNode(), constructor);
ctorVar.useSourceInfoIfMissingFromForTree(classNode);
parent.replaceChild(classNode, ctorVar);
} else {
parent.replaceChild(classNode, constructor);
}
if (NodeUtil.isStatement(constructor)) {
constructor.setJSDocInfo(newInfo.build());
} else if (parent.isName()) {
// The constructor function is the RHS of a var statement.
// Add the JSDoc to the VAR node.
Node var = parent.getParent();
var.setJSDocInfo(newInfo.build());
} else if (constructor.getParent().isName()) {
// Is a newly created VAR node.
Node var = constructor.getParent().getParent();
var.setJSDocInfo(newInfo.build());
} else if (parent.isAssign()) {
// The constructor function is the RHS of an assignment.
// Add the JSDoc to the ASSIGN node.
parent.setJSDocInfo(newInfo.build());
} else {
throw new IllegalStateException("Unexpected parent node " + parent);
}
compiler.reportCodeChange();
}
private void visitArrayPattern(NodeTraversal t, Node arrayPattern, Node parent) {
Node rhs, nodeToDetach;
if (NodeUtil.isNameDeclaration(parent) && !NodeUtil.isEnhancedFor(parent.getParent())) {
// The array pattern is the only child, because Es6SplitVariableDeclarations
// has already run.
Preconditions.checkState(arrayPattern.getNext() == null);
rhs = arrayPattern.getLastChild();
nodeToDetach = parent;
} else if (parent.isAssign()) {
rhs = arrayPattern.getNext();
nodeToDetach = parent.getParent();
Preconditions.checkState(nodeToDetach.isExprResult());
} else if (parent.isArrayPattern() || parent.isDefaultValue() || parent.isStringKey()) {
// This is a nested array pattern. Don't do anything now; we'll visit it
// after visiting the parent.
return;
} else if (NodeUtil.isEnhancedFor(parent) || NodeUtil.isEnhancedFor(parent.getParent())) {
visitDestructuringPatternInEnhancedFor(arrayPattern);
return;
} else {
Preconditions.checkState(parent.isCatch() || parent.isForOf());
cannotConvertYet(
arrayPattern, "ARRAY_PATTERN that is a child of a " + Token.name(parent.getType()));
return;
}
// Convert 'var [x, y] = rhs' to:
// var temp = rhs;
// var x = temp[0];
// var y = temp[1];
String tempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
Node tempDecl =
IR.var(IR.name(tempVarName), rhs.detachFromParent())
.useSourceInfoIfMissingFromForTree(arrayPattern);
nodeToDetach.getParent().addChildBefore(tempDecl, nodeToDetach);
int i = 0;
for (Node child = arrayPattern.getFirstChild(), next; child != null; child = next, i++) {
next = child.getNext();
if (child.isEmpty()) {
continue;
}
Node newLHS, newRHS;
if (child.isDefaultValue()) {
Node getElem = IR.getelem(IR.name(tempVarName), IR.number(i));
// [x = defaultValue] = rhs;
// becomes
// var temp = rhs;
// x = (temp[0] === undefined) ? defaultValue : temp[0];
newLHS = child.getFirstChild().detachFromParent();
newRHS = defaultValueHook(getElem, child.getLastChild().detachFromParent());
} else if (child.isRest()) {
newLHS = child.detachFromParent();
newLHS.setType(Token.NAME);
// [].slice.call(temp, i)
newRHS =
IR.call(
IR.getprop(IR.getprop(IR.arraylit(), IR.string("slice")), IR.string("call")),
IR.name(tempVarName),
IR.number(i));
} else {
newLHS = child.detachFromParent();
newRHS = IR.getelem(IR.name(tempVarName), IR.number(i));
}
Node newNode;
if (parent.isAssign()) {
Node assignment = IR.assign(newLHS, newRHS);
newNode = IR.exprResult(assignment);
} else {
newNode = IR.declaration(newLHS, newRHS, parent.getType());
}
newNode.useSourceInfoIfMissingFromForTree(arrayPattern);
nodeToDetach.getParent().addChildBefore(newNode, nodeToDetach);
// Explicitly visit the LHS of the new node since it may be a nested
// destructuring pattern.
visit(t, newLHS, newLHS.getParent());
}
nodeToDetach.detachFromParent();
compiler.reportCodeChange();
}
private void visitClass(Node classNode, Node parent) {
Node className = classNode.getFirstChild();
Node superClassName = className.getNext();
Node classMembers = classNode.getLastChild();
// This is a statement node. We insert methods of the
// transpiled class after this node.
Node insertionPoint;
// The fully qualified name of the class, which will be used in the output.
// May come from the class itself or the LHS of an assignment.
String fullClassName = null;
// Whether the constructor function in the output should be anonymous.
boolean anonymous;
// If this is a class statement, or a class expression in a simple
// assignment or var statement, convert it. In any other case, the
// code is too dynamic, so just call cannotConvert.
if (NodeUtil.isStatement(classNode)) {
fullClassName = className.getString();
anonymous = false;
insertionPoint = classNode;
} else if (parent.isAssign() && parent.getParent().isExprResult()) {
// Add members after the EXPR_RESULT node:
// example.C = class {}; example.C.prototype.foo = function() {};
fullClassName = parent.getFirstChild().getQualifiedName();
if (fullClassName == null) {
cannotConvert(parent);
return;
}
anonymous = true;
insertionPoint = parent.getParent();
} else if (parent.isName()) {
// Add members after the 'var' statement.
// var C = class {}; C.prototype.foo = function() {};
fullClassName = parent.getString();
anonymous = true;
insertionPoint = parent.getParent();
} else {
cannotConvert(parent);
return;
}
Verify.verify(NodeUtil.isStatement(insertionPoint));
className.detachFromParent();
Node constructor = null;
JSDocInfo ctorJSDocInfo = null;
for (Node member : classMembers.children()) {
if (member.getString().equals("constructor")) {
ctorJSDocInfo = member.getJSDocInfo();
constructor = member.getFirstChild().detachFromParent();
if (!anonymous) {
constructor.replaceChild(constructor.getFirstChild(), className);
}
} else {
String qualifiedMemberName;
if (member.isStaticMember()) {
if (NodeUtil.referencesThis(member.getFirstChild())) {
compiler.report(JSError.make(member, STATIC_METHOD_REFERENCES_THIS));
}
qualifiedMemberName = Joiner.on(".").join(fullClassName, member.getString());
} else {
qualifiedMemberName = Joiner.on(".").join(fullClassName, "prototype", member.getString());
}
Node assign =
IR.assign(
NodeUtil.newQualifiedNameNode(
compiler.getCodingConvention(),
qualifiedMemberName,
/* basis node */ member,
/* original name */ member.getString()),
member.getFirstChild().detachFromParent());
assign.srcref(member);
JSDocInfo info = member.getJSDocInfo();
if (info != null) {
info.setAssociatedNode(assign);
assign.setJSDocInfo(info);
}
Node newNode = NodeUtil.newExpr(assign);
insertionPoint.getParent().addChildAfter(newNode, insertionPoint);
insertionPoint = newNode;
}
}
if (constructor == null) {
Node name = anonymous ? IR.name("").srcref(className) : className;
constructor =
IR.function(name, IR.paramList().srcref(classNode), IR.block().srcref(classNode));
}
JSDocInfo classJSDoc = classNode.getJSDocInfo();
JSDocInfoBuilder newInfo =
(classJSDoc != null) ? JSDocInfoBuilder.copyFrom(classJSDoc) : new JSDocInfoBuilder(true);
newInfo.recordConstructor();
if (!superClassName.isEmpty()) {
if (!superClassName.isQualifiedName()) {
compiler.report(JSError.make(superClassName, DYNAMIC_EXTENDS_TYPE));
return;
}
Node superClassString = IR.string(superClassName.getQualifiedName());
if (newInfo.isInterfaceRecorded()) {
newInfo.recordExtendedInterface(
new JSTypeExpression(
new Node(Token.BANG, superClassString), superClassName.getSourceFileName()));
} else {
// TODO(mattloring) Remove dependency on Closure Library.
Node inherits =
NodeUtil.newQualifiedNameNode(compiler.getCodingConvention(), "goog.inherits");
Node inheritsCall =
IR.exprResult(IR.call(inherits, className.cloneTree(), superClassName.cloneTree()));
inheritsCall.useSourceInfoIfMissingFromForTree(classNode);
parent.addChildAfter(inheritsCall, classNode);
newInfo.recordBaseType(
new JSTypeExpression(
new Node(Token.BANG, superClassString), superClassName.getSourceFileName()));
}
}
// Classes are @struct by default.
if (!newInfo.isUnrestrictedRecorded()
&& !newInfo.isDictRecorded()
&& !newInfo.isStructRecorded()) {
newInfo.recordStruct();
}
if (ctorJSDocInfo != null) {
newInfo.recordSuppressions(ctorJSDocInfo.getSuppressions());
for (String param : ctorJSDocInfo.getParameterNames()) {
newInfo.recordParameter(param, ctorJSDocInfo.getParameterType(param));
}
}
parent.replaceChild(classNode, constructor);
if (NodeUtil.isStatement(constructor)) {
constructor.setJSDocInfo(newInfo.build(constructor));
} else if (parent.isName()) {
// The constructor function is the RHS of a var statement.
// Add the JSDoc to the VAR node.
Node var = parent.getParent();
var.setJSDocInfo(newInfo.build(var));
} else if (parent.isAssign()) {
// The constructor function is the RHS of an assignment.
// Add the JSDoc to the ASSIGN node.
parent.setJSDocInfo(newInfo.build(parent));
} else {
throw new IllegalStateException("Unexpected parent node " + parent);
}
compiler.reportCodeChange();
}
private Node tryFoldAssign(Node n, Node left, Node right) {
Preconditions.checkArgument(n.isAssign());
if (!late) {
return n;
}
// Tries to convert x = x + y -> x += y;
if (!right.hasChildren() || right.getSecondChild() != right.getLastChild()) {
// RHS must have two children.
return n;
}
if (mayHaveSideEffects(left)) {
return n;
}
Node newRight;
if (areNodesEqualForInlining(left, right.getFirstChild())) {
newRight = right.getLastChild();
} else if (NodeUtil.isCommutative(right.getType())
&& areNodesEqualForInlining(left, right.getLastChild())) {
newRight = right.getFirstChild();
} else {
return n;
}
Token newType = null;
switch (right.getType()) {
case ADD:
newType = Token.ASSIGN_ADD;
break;
case BITAND:
newType = Token.ASSIGN_BITAND;
break;
case BITOR:
newType = Token.ASSIGN_BITOR;
break;
case BITXOR:
newType = Token.ASSIGN_BITXOR;
break;
case DIV:
newType = Token.ASSIGN_DIV;
break;
case LSH:
newType = Token.ASSIGN_LSH;
break;
case MOD:
newType = Token.ASSIGN_MOD;
break;
case MUL:
newType = Token.ASSIGN_MUL;
break;
case RSH:
newType = Token.ASSIGN_RSH;
break;
case SUB:
newType = Token.ASSIGN_SUB;
break;
case URSH:
newType = Token.ASSIGN_URSH;
break;
default:
return n;
}
Node newNode = new Node(newType, left.detachFromParent(), newRight.detachFromParent());
n.getParent().replaceChild(n, newNode);
reportCodeChange();
return newNode;
}
private void rewritePolymerClass(Node exprRoot, final ClassDefinition cls, NodeTraversal t) {
// Add {@code @lends} to the object literal.
Node call = exprRoot.getFirstChild();
if (call.isAssign()) {
call = call.getChildAtIndex(1);
} else if (call.isName()) {
call = call.getFirstChild();
}
Node objLit = cls.descriptor;
if (hasShorthandAssignment(objLit)) {
compiler.report(JSError.make(objLit, POLYMER_SHORTHAND_NOT_SUPPORTED));
return;
}
JSDocInfoBuilder objLitDoc = new JSDocInfoBuilder(true);
objLitDoc.recordLends(cls.target.getQualifiedName() + ".prototype");
objLit.setJSDocInfo(objLitDoc.build());
this.addTypesToFunctions(objLit, cls.target.getQualifiedName());
this.switchDollarSignPropsToBrackets(objLit);
this.quoteListenerAndHostAttributeKeys(objLit);
// For simplicity add everything into a block, before adding it to the AST.
Node block = IR.block();
if (cls.nativeBaseElement != null) {
this.appendPolymerElementExterns(cls);
}
JSDocInfoBuilder constructorDoc = this.getConstructorDoc(cls);
// Remove the original constructor JS docs from the objlit.
Node ctorKey = cls.constructor.value.getParent();
if (ctorKey != null) {
ctorKey.removeProp(Node.JSDOC_INFO_PROP);
}
if (cls.target.isGetProp()) {
// foo.bar = Polymer({...});
Node assign = IR.assign(cls.target.cloneTree(), cls.constructor.value.cloneTree());
assign.setJSDocInfo(constructorDoc.build());
Node exprResult = IR.exprResult(assign);
block.addChildToBack(exprResult);
} else {
// var foo = Polymer({...}); OR Polymer({...});
Node var = IR.var(cls.target.cloneTree(), cls.constructor.value.cloneTree());
var.setJSDocInfo(constructorDoc.build());
block.addChildToBack(var);
}
appendPropertiesToBlock(cls, block, cls.target.getQualifiedName() + ".prototype.");
appendBehaviorMembersToBlock(cls, block);
List<MemberDefinition> readOnlyProps = parseReadOnlyProperties(cls, block);
addInterfaceExterns(cls, readOnlyProps);
removePropertyDocs(objLit);
block.useSourceInfoIfMissingFromForTree(exprRoot);
Node stmts = block.removeChildren();
Node parent = exprRoot.getParent();
// If the call to Polymer() is not in the global scope and the assignment target is not
// namespaced (which likely means it's exported to the global scope), put the type declaration
// into the global scope at the start of the current script.
//
// This avoids unknown type warnings which are a result of the compiler's poor understanding of
// types declared inside IIFEs or any non-global scope. We should revisit this decision after
// moving to the new type inference system which should be able to infer these types better.
if (!t.getScope().isGlobal() && !cls.target.isGetProp()) {
Node scriptNode = NodeUtil.getEnclosingScript(exprRoot);
scriptNode.addChildrenToFront(stmts);
} else {
Node beforeRoot = parent.getChildBefore(exprRoot);
if (beforeRoot == null) {
parent.addChildrenToFront(stmts);
} else {
parent.addChildrenAfter(stmts, beforeRoot);
}
}
if (exprRoot.isVar()) {
Node assignExpr = varToAssign(exprRoot);
parent.replaceChild(exprRoot, assignExpr);
}
compiler.reportCodeChange();
}
boolean isSimpleAssignmentToName() {
Node parent = getParent();
return parent.isAssign() && parent.getFirstChild() == nameNode;
}
private void visitObjectPattern(NodeTraversal t, Node objectPattern, Node parent) {
Node rhs, nodeToDetach;
if (NodeUtil.isNameDeclaration(parent) && !NodeUtil.isEnhancedFor(parent.getParent())) {
rhs = objectPattern.getLastChild();
nodeToDetach = parent;
} else if (parent.isAssign() && parent.getParent().isExprResult()) {
rhs = parent.getLastChild();
nodeToDetach = parent.getParent();
} else if (parent.isStringKey() || parent.isArrayPattern() || parent.isDefaultValue()) {
// Nested object pattern; do nothing. We will visit it after rewriting the parent.
return;
} else if (NodeUtil.isEnhancedFor(parent) || NodeUtil.isEnhancedFor(parent.getParent())) {
visitDestructuringPatternInEnhancedFor(objectPattern);
return;
} else {
Preconditions.checkState(parent.isCatch(), parent);
cannotConvertYet(
objectPattern, "OBJECT_PATTERN that is a child of a " + Token.name(parent.getType()));
return;
}
// Convert 'var {a: b, c: d} = rhs' to:
// var temp = rhs;
// var b = temp.a;
// var d = temp.c;
String tempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
Node tempDecl =
IR.var(IR.name(tempVarName), rhs.detachFromParent())
.useSourceInfoIfMissingFromForTree(objectPattern);
nodeToDetach.getParent().addChildBefore(tempDecl, nodeToDetach);
for (Node child = objectPattern.getFirstChild(), next; child != null; child = next) {
next = child.getNext();
Node newLHS, newRHS;
if (child.isStringKey()) {
Preconditions.checkState(child.hasChildren());
Node getprop =
new Node(
child.isQuotedString() ? Token.GETELEM : Token.GETPROP,
IR.name(tempVarName),
IR.string(child.getString()));
Node value = child.removeFirstChild();
if (!value.isDefaultValue()) {
newLHS = value;
newRHS = getprop;
} else {
newLHS = value.removeFirstChild();
Node defaultValue = value.removeFirstChild();
newRHS = defaultValueHook(getprop, defaultValue);
}
} else if (child.isComputedProp()) {
if (child.getLastChild().isDefaultValue()) {
newLHS = child.getLastChild().removeFirstChild();
Node getelem = IR.getelem(IR.name(tempVarName), child.removeFirstChild());
String intermediateTempVarName = DESTRUCTURING_TEMP_VAR + (destructuringVarCounter++);
Node intermediateDecl = IR.var(IR.name(intermediateTempVarName), getelem);
intermediateDecl.useSourceInfoIfMissingFromForTree(child);
nodeToDetach.getParent().addChildBefore(intermediateDecl, nodeToDetach);
newRHS =
defaultValueHook(
IR.name(intermediateTempVarName), child.getLastChild().removeFirstChild());
} else {
newRHS = IR.getelem(IR.name(tempVarName), child.removeFirstChild());
newLHS = child.removeFirstChild();
}
} else if (child.isDefaultValue()) {
newLHS = child.removeFirstChild();
Node defaultValue = child.removeFirstChild();
Node getprop = IR.getprop(IR.name(tempVarName), IR.string(newLHS.getString()));
newRHS = defaultValueHook(getprop, defaultValue);
} else {
throw new IllegalStateException("Unexpected OBJECT_PATTERN child: " + child);
}
Node newNode;
if (NodeUtil.isNameDeclaration(parent)) {
newNode = IR.declaration(newLHS, newRHS, parent.getType());
} else if (parent.isAssign()) {
newNode = IR.exprResult(IR.assign(newLHS, newRHS));
} else {
throw new IllegalStateException("not reached");
}
newNode.useSourceInfoIfMissingFromForTree(child);
nodeToDetach.getParent().addChildBefore(newNode, nodeToDetach);
// Explicitly visit the LHS of the new node since it may be a nested
// destructuring pattern.
visit(t, newLHS, newLHS.getParent());
}
nodeToDetach.detachFromParent();
compiler.reportCodeChange();
}