next step toward completion plugin API

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

 // Copyright (c) 2015, 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.invocation;
 
+import 'dart:async';
+
 import 'package:analysis_server/plugin/edit/utilities/change_builder_dart.dart';
 import 'package:analysis_server/src/protocol_server.dart'
     show CompletionSuggestion, CompletionSuggestionKind, SourceChange;
 import 'package:analysis_server/src/protocol_server.dart' as protocol
     hide CompletionSuggestion, CompletionSuggestionKind;
 import 'package:analysis_server/src/provisional/completion/completion_dart.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart'
     show DART_RELEVANCE_HIGH;
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/src/task/dart.dart';
+import 'package:analyzer/task/model.dart';
+import 'package:analysis_server/src/provisional/completion/dart/completion_target.dart';
 
 /**
  * A completion contributor used to suggest replacing partial identifiers inside
  * a class declaration with templates for inherited members.
  */
 class InheritedContributor extends DartCompletionContributor {
   @override
-  List<CompletionSuggestion> internalComputeSuggestions(
-      DartCompletionRequest request) {
-    if (!request.isResolved) {
-      return null;
-    }
-    AstNode node = new NodeLocator(request.offset).searchWithin(request.unit);
-    if (node == null || !_isMemberLevelIdentifier(node)) {
-      return null;
-    }
-    ClassDeclaration classDeclaration =
-        node.getAncestor((AstNode node) => node is ClassDeclaration);
-    if (classDeclaration != null) {
-      ClassElement element = classDeclaration.element;
-      if (element == null) {
-        return null;
-      }
-      return _suggestInheritedMembers(request, node, element);
+  Future computeSuggestions(
+      DartCompletionRequest request, DartSuggestionCollector collector) {
+    if (request.parsedTarget.containingNode is ClassDeclaration) {
+      return request.resolvedDeclarationTarget
+          .then((CompletionTarget resolvedTarget) {
+        _suggestInheritedMembers(
+            request,
+            (resolvedTarget.containingNode as ClassDeclaration).element,
+            collector);
+      });
     }
     return null;
   }
 
   /**
    * Return a template for an override of the given [element] in the given
    * [source]. If selected, the template will replace the given [identifier].
    */
-  String _buildRepacementText(
-      Source source, SimpleIdentifier identifier, Element element) {
-    AnalysisContext context = element.context;
+  String _buildRepacementText(DartCompletionRequest request, Element element) {
+    AnalysisContext context = request.context;
     DartChangeBuilder builder = new DartChangeBuilder(context);
-    builder.addFileEdit(source, context.getModificationStamp(source),
+    builder.addFileEdit(
+        request.source, context.getModificationStamp(request.source),
         (DartFileEditBuilder builder) {
-      builder.addReplacement(identifier.offset, identifier.length,
-          (DartEditBuilder builder) {
+      builder.addReplacement(0, 0, (DartEditBuilder builder) {
         builder.writeOverrideOfInheritedMember(element);
       });
     });
     return builder.sourceChange.edits[0].edits[0].replacement.trim();
   }
 
   /**
    * Build a suggestion to replace the partial [identifier] in the given
    * [source] with an override of the given [element].
    */
   CompletionSuggestion _buildSuggestion(
-      Source source, SimpleIdentifier identifier, Element element) {
-    String completion = _buildRepacementText(source, identifier, element);
+      DartCompletionRequest request, Element element) {
+    String completion = _buildRepacementText(request, element);
     CompletionSuggestion suggestion = new CompletionSuggestion(
         CompletionSuggestionKind.IDENTIFIER,
         DART_RELEVANCE_HIGH,
         completion,
-        identifier.offset,
         0,
+        completion.length,
         element.isDeprecated,
         false);
     suggestion.element = protocol.convertElement(element);
     return suggestion;
   }
 
   /**
    * Return a list containing the names of all of the inherited by not
    * implemented members of the class represented by the given [element] that
    * start with the given [prefix]. The [map] is used to find all of the members
    * that are inherited.
    */
-  List<String> _computeMemberNames(
-      MemberMap map, ClassElement element, String prefix) {
+  List<String> _computeMemberNames(MemberMap map, ClassElement element) {
     List<String> memberNames = <String>[];
     int count = map.size;
+    RegExp prefix = new RegExp('[A-Za-z_]');
     for (int i = 0; i < count; i++) {
       String memberName = map.getKey(i);
       if (memberName.startsWith(prefix) && !_hasMember(element, memberName)) {
         memberNames.add(memberName);
       }
     }
     return memberNames;
   }
 
   /**
    * Return `true` if the given [classElement] directly declares a member with
    * the given [memberName].
    */
   bool _hasMember(ClassElement classElement, String memberName) {
     return classElement.getField(memberName) != null ||
         classElement.getGetter(memberName) != null ||
         classElement.getMethod(memberName) != null ||
         classElement.getSetter(memberName) != null;
   }
 
   /**
-   * Return `true` if the given [node] looks like a partial identifier inside a
-   * class declaration.
-   */
-  bool _isMemberLevelIdentifier(AstNode node) {
-    if (node is SimpleIdentifier) {
-      AstNode parent1 = node.parent;
-      if (parent1 is TypeName) {
-        AstNode parent2 = parent1.parent;
-        if (parent2 is VariableDeclarationList) {
-          AstNode parent3 = parent2.parent;
-          if (parent3 is FieldDeclaration) {
-            NodeList<VariableDeclaration> variables = parent2.variables;
-            return variables.length == 1 && variables[0].name.name.isEmpty;
-          }
-        }
-      }
-    }
-    return false;
-  }
-
-  /**
    * Add any suggestions that are appropriate to the given [request], using the
    * given [element] to find inherited members whose name has the given
    * [identifier] as a prefix.
    */
-  List<CompletionSuggestion> _suggestInheritedMembers(
-      DartCompletionRequest request,
-      SimpleIdentifier identifier,
-      ClassElement element) {
-    String name = identifier.name;
+  void _suggestInheritedMembers(DartCompletionRequest request,
+      ClassElement element, DartSuggestionCollector collector) {
     InheritanceManager manager = new InheritanceManager(element.library);
     MemberMap map = manager.getMapOfMembersInheritedFromInterfaces(element);
-    List<String> memberNames = _computeMemberNames(map, element, name);
+    List<String> memberNames = _computeMemberNames(map, element);
     memberNames.sort();
-    List<CompletionSuggestion> suggestions = <CompletionSuggestion>[];
     for (String memberName in memberNames) {
-      CompletionSuggestion suggestion =
-          _buildSuggestion(request.source, identifier, map.get(memberName));
-      if (suggestion != null) {
-        suggestions.add(suggestion);
-      }
+      collector.addCompletionSuggestion(
+          _buildSuggestion(request, map.get(memberName)));
     }
-    return suggestions;
   }
 }