Resolve initializers in constructors.

frog/leg/resolver.dart

Index: frog/leg/resolver.dart
diff --git a/frog/leg/resolver.dart b/frog/leg/resolver.dart
index 5385643239268eff3fc5a95883dbd50667327e3e..4b1fd25b426607ca805d104c01b3b9f5cd529cf7 100644
--- a/frog/leg/resolver.dart
+++ b/frog/leg/resolver.dart
@@ -20,14 +20,13 @@ class ResolverTask extends CompilerTask {
   TreeElements resolve(FunctionElement element) {
     return measure(() {
       FunctionExpression tree = element.parseNode(compiler, compiler);
-      if (tree.initializers !== null) {
-        compiler.cancel('initializers are not implemented',
-                        node: tree.initializers);
-      }
       ResolverVisitor visitor = new SignatureResolverVisitor(compiler, element);
       visitor.visit(tree);
 
       visitor = new FullResolverVisitor.from(visitor);
+      if (tree.initializers != null) {
+        resolveInitializers(element, tree, visitor);
+      }
       visitor.visit(tree.body);
 
       // Resolve the type annotations encountered in the method.
@@ -38,6 +37,42 @@ class ResolverTask extends CompilerTask {
     });
   }
 
+  void resolveInitializers(element, node, visitor) {

[ngeoffray, 2011/12/21 11:52:11]

Types on parameters?

[ahe, 2011/12/21 12:01:58]

I'd like a type on node.

[karlklose, 2011/12/21 16:33:46]

Done.

[karlklose, 2011/12/21 16:33:46]

Done.

+    Map<SourceString, Node> initialized = new Map<SourceString, Node>();
+    for (Link<Node> link = node.initializers.nodes;
+         !link.isEmpty();
+         link = link.tail) {
+      if (link.head.asSendSet() != null) {
+        SendSet init = link.head;
+        SourceString name = init.getInitializerFieldName(
+          () => visitor.error(init,
+                              MessageKind.INVALID_RECEIVER_IN_INITIALIZER));
+        ClassElement classElement = element.enclosingElement;
+        Element target = classElement.lookupLocalElement(name);
+        Node selector = init.selector;
+        if (target == null) {
+          visitor.error(selector, MessageKind.CANNOT_RESOLVE, [name]);
+        } else if (target.kind != ElementKind.FIELD) {
+          visitor.error(selector, MessageKind.NOT_A_FIELD, [name]);
+        } else if (!target.isInstanceMember()) {
+          visitor.error(selector, MessageKind.INIT_STATIC_FIELD, [name]);
+        }
+        visitor.useElement(init, target);
+        if (initialized.containsKey(name)) {
+          visitor.warning(init, MessageKind.DUPLICATE_INITIALIZER,

[ngeoffray, 2011/12/21 11:52:11]

The spec says it's a compile time error, so should that be a visitor.error?

[karlklose, 2011/12/21 16:33:46]

Done.

+                          [name, initialized[name]]);
+        }
+        initialized[name] = init;
+        Node value = init.arguments.head;
+        visitor.visitInStaticContext(value);
+      } else {
+        // TODO(karlklose): super(...), this(...).
+        compiler.cancel('internal error: invalid initializer',

[ngeoffray, 2011/12/21 11:52:11]

invalid -> unimplemented

[ahe, 2011/12/21 12:01:58]

This is not an internal error, and the initializer is not invalid. I would just
say "unimplemented".

[karlklose, 2011/12/21 16:33:46]

Done.

[karlklose, 2011/12/21 16:33:46]

Done.

+                        node: link.head);
+      }
+    }
+  }
+
   void resolveType(ClassElement element) {
     measure(() {
       ClassNode tree = element.node;
@@ -61,6 +96,7 @@ class ResolverVisitor implements Visitor<Element> {
   final TreeElements mapping;
   final Element enclosingElement;
   Scope context;
+  bool isStaticContext;

[ngeoffray, 2011/12/21 11:52:11]

isStaticContext always looks weird to me (is it a static method, meaning does it
have the static modifier?). I'd rather have a 'inInstanceContext'. This field
should be set during construction of the visitor:

inInstanceContext = element.isInstanceMember().

We could then use it for closures.

[karlklose, 2011/12/21 16:33:46]

Done.

 
   ResolverVisitor(Compiler compiler, Element element)
     : this.compiler = compiler,
@@ -68,7 +104,8 @@ class ResolverVisitor implements Visitor<Element> {
       this.enclosingElement = element,
       this.context  = element.isMember()
         ? new ClassScope(element.enclosingElement, compiler.universe)
-        : new TopScope(compiler.universe);
+        : new TopScope(compiler.universe),
+      this.isStaticContext = false;
 
   ResolverVisitor.from(ResolverVisitor other)
     : compiler = other.compiler,
@@ -90,13 +127,28 @@ class ResolverVisitor implements Visitor<Element> {
     compiler.cancel(message);
   }
 
+  Element lookup(Node node, SourceString name) {
+    Element result = context.lookup(name);
+    if (isStaticContext && result != null && result.isInstanceMember()) {
+      error(node, MessageKind.NOT_STATIC, [node]);
+    }
+    return result;
+  }
+
+  visitInStaticContext(Node node) {
+    bool wasStaticContext = isStaticContext;
+    isStaticContext = true;
+    visit(node);
+    isStaticContext = wasStaticContext;
+  }
+
   visit(Node node) {
     if (node == null) return null;
     return node.accept(this);
   }
 
   visitIdentifier(Identifier node) {
-    Element element = context.lookup(node.source);
+    Element element = lookup(node, node.source);
     if (element == null) {
       error(node, MessageKind.CANNOT_RESOLVE, [node]);
     }
@@ -146,7 +198,6 @@ class SignatureResolverVisitor extends ResolverVisitor {
   visitFunctionExpression(FunctionExpression node) {
     useElement(node, element);
     context = new MethodScope(context, element);
-
     if (element.parameters == null) {
       ParametersVisitor visitor = new ParametersVisitor(this);
       visitor.visit(node.parameters);
@@ -300,7 +351,7 @@ class FullResolverVisitor extends ResolverVisitor {
       SourceString opName = mapOperatorToMethodName(name, node.isPrefix);
       target = compiler.universe.find(opName);
     } else if (node.receiver === null) {
-      target = context.lookup(name);
+      target = lookup(node, name);

[ngeoffray, 2011/12/21 11:52:11]

I think this should be changed to target = visit(node.selector);

[karlklose, 2011/12/21 16:33:46]

Done.

       if (target == null && !enclosingElement.isInstanceMember()) {
         error(node, MessageKind.CANNOT_RESOLVE, [name]);
       }
@@ -344,7 +395,7 @@ class FullResolverVisitor extends ResolverVisitor {
       if (node.isIndex) {
         getter = target;
       } else {
-        getter = context.lookup(node.selector.asIdentifier().source);
+        getter = lookup(node, node.selector.asIdentifier().source);

[ngeoffray, 2011/12/21 11:52:11]

ditto.

[karlklose, 2011/12/21 16:33:46]

Done.

       }
       useElement(node.selector, getter);
     }
@@ -566,7 +617,7 @@ class Scope {
 
   Scope(this.parent, this.element);
   abstract Element add(Element element);
-  abstract Element lookup(Element element);
+  abstract Element lookup(SourceString name);
 }
 
 class MethodScope extends Scope {