Improve 'length' instance property reference encoding.

pkg/analyzer/lib/src/summary/summarize_const_expr.dart

 // 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 serialization.summarize_const_expr;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/scanner.dart';
 import 'package:analyzer/src/summary/format.dart';
 
@@ skipping 75 matching lines @@
     } else if (expr is BinaryExpression) {
       _serializeBinaryExpression(expr);
     } else if (expr is ConditionalExpression) {
       serialize(expr.condition);
       serialize(expr.thenExpression);
       serialize(expr.elseExpression);
       operations.add(UnlinkedConstOperation.conditional);
     } else if (expr is PrefixExpression) {
       _serializePrefixExpression(expr);
     } else if (expr is PropertyAccess) {
-      // TODO(scheglov) solve ambiguity of `a.b.length` where `a` and `b` are
-      // identifiers
-      if (expr.propertyName.name == 'length') {
+      if (expr.target is StringLiteral && expr.propertyName.name == 'length') {

[Paul Berry, 2016/01/27 16:48:59]

I think this should be:

    if (expr.target is! PrefixedIdentifier && expr.propertyName.name ==
'length')

That way we correctly handle cases like:

    const x = ('abc' + 'def').length;

and:

    const x = ('abc').length;

[scheglov, 2016/01/27 17:55:10]

Done.

         serialize(expr.target);
         operations.add(UnlinkedConstOperation.length);
       } else {
         references.add(serializePropertyAccess(expr));
         operations.add(UnlinkedConstOperation.pushReference);
       }
     } else if (expr is ParenthesizedExpression) {
       serialize(expr.expression);
     } else {
       throw new _ConstExprSerializationError('Unknown expression type: $expr');
     }
   }
 
   /**
+   * Return [EntityRefBuilder] that corresponds to the given [constructor].
+   */
+  EntityRefBuilder serializeConstructorName(ConstructorName constructor);
+
+  /**
    * Return [EntityRefBuilder] that corresponds to the given [identifier].
    */
   EntityRefBuilder serializeIdentifier(Identifier identifier);
 
   /**
    * Return [EntityRefBuilder] that corresponds to the given [access].
    */
   EntityRefBuilder serializePropertyAccess(PropertyAccess access);
 
   /**
    * Return [EntityRefBuilder] that corresponds to the given [type].
    */
   EntityRefBuilder serializeType(TypeName type);
 
   /**
-   * Return [EntityRefBuilder] that corresponds to the given [constructor].
-   */
-  EntityRefBuilder serializeConstructorName(ConstructorName constructor);
-
-  /**
    * Return the [UnlinkedConstBuilder] that corresponds to the state of this
    * serializer.
    */
   UnlinkedConstBuilder toBuilder() {
     return new UnlinkedConstBuilder(
         operations: operations,
         ints: ints,
         doubles: doubles,
         strings: strings,
         references: references);
@@ skipping 157 matching lines @@
  * Error that describes a problem during a constant expression serialization.
  */
 class _ConstExprSerializationError {
   final String message;
 
   _ConstExprSerializationError(this.message);
 
   @override
   String toString() => message;
 }