binary expression suggestion fix

pkg/analysis_server/lib/src/services/completion/imported_computer.dart

 // Copyright (c) 2014, 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 services.completion.computer.dart.toplevel;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol_server.dart' hide Element,
     ElementKind;
@@ skipping 51 matching lines @@
     }
     return new Future.value(false);
   }
 
   @override
   Future<bool> visitCombinator(Combinator node) {
     return _addCombinatorSuggestions(node);
   }
 
   @override
+  Future<bool> visitExpression(Expression node) {
+    return _addImportedElementSuggestions();
+  }
+
+  @override
   Future<bool> visitExpressionStatement(ExpressionStatement node) {
     Expression expression = node.expression;
     // A pre-variable declaration (e.g. C ^) is parsed as an expression
     // statement. Do not make suggestions for the variable name.
     if (expression is SimpleIdentifier && request.offset <= expression.end) {
       return _addImportedElementSuggestions();
     }
     return new Future.value(false);
   }
 
   @override
   Future<bool> visitNode(AstNode node) {
     return new Future.value(false);
   }
 
   @override
   Future<bool> visitPrefixedIdentifier(PrefixedIdentifier node) {
     // Make suggestions for the prefix, but not for the selector
     // InvocationComputer makes selector suggestions
-    if (request.offset <= node.prefix.end) {
+    Token period = node.period;
+    if (period != null && request.offset <= period.offset) {
       return _addImportedElementSuggestions();
     }
     return new Future.value(false);
+  }
+
+  @override
+  Future<bool> visitPropertyAccess(PropertyAccess node) {
+    // Make suggestions for the target, but not for the property name
+    // InvocationComputer makes property name suggestions
+    var operator = node.operator;
+    if (operator != null && request.offset < operator.offset) {
+      return _addImportedElementSuggestions();
+    }
+    return new Future.value(false);
   }
 
   @override
   Future<bool> visitSimpleIdentifier(SimpleIdentifier node) {
     return node.parent.accept(this);
   }
 
   @override
+  Future<bool> visitStringLiteral(StringLiteral node) {
+    return new Future.value(false);
+  }
+
+  @override
   Future<bool> visitTypeName(TypeName node) {
     return _addImportedElementSuggestions(typesOnly: true);
   }
 
   @override
   visitVariableDeclaration(VariableDeclaration node) {
     Token equals = node.equals;
     // Make suggestions for the RHS of a variable declaration
     if (equals != null && request.offset >= equals.end) {
       return _addImportedElementSuggestions();
@@ skipping 122 matching lines @@
           importElem.isDeprecated,
           false);
       LibraryElement lib = importElem.importedLibrary;
       if (lib != null) {
         suggestion.element = newElement_fromEngine(lib);
       }
       request.suggestions.add(suggestion);
     }
   }
 }