next step toward completion plugin API

pkg/analysis_server/lib/src/services/completion/completion_dart.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 analysis_server.src.services.completion.completion_dart;
 
+import 'dart:async';
+
 import 'package:analysis_server/src/provisional/completion/completion_core.dart';
 import 'package:analysis_server/src/provisional/completion/completion_dart.dart';
 import 'package:analysis_server/src/provisional/completion/dart/completion_target.dart';
 import 'package:analysis_server/src/services/completion/completion_core.dart';
+import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/generated/ast.dart';
+import 'package:analyzer/src/task/dart.dart';
+import 'package:analyzer/task/dart.dart';
+import 'package:analyzer/task/model.dart';
+import 'package:analyzer/src/generated/element.dart';
 
 /**
  * The information about a requested list of completions within a Dart file.
  */
 class DartCompletionRequestImpl extends CompletionRequestImpl
     implements DartCompletionRequest {
   /**
-   * The compilation unit in which the completion was requested.
+   * The parsed completion target.  This determines
+   * what part of the parse tree will receive the newly inserted text.
+   * Use [resolvedDeclarationTarget] to obtain a resolved completion target.
    */
-  final CompilationUnit unit;
+  final CompletionTarget parsedTarget;
 
-  /**
-   * A flag indicating whether the compilation [unit] is resolved.
-   */
-  final bool isResolved;
+  @deprecated // Use parsedTarget
+  CompletionTarget get target => parsedTarget;
 
-  /**
-   * The completion target.  This determines what part of the parse tree
-   * will receive the newly inserted text.
-   */
-  final CompletionTarget target;
+  @deprecated // Use parsedTarget.unit or resolvedTarget(...).unit
+  CompilationUnit get unit => parsedTarget.unit;
 
   /**
    * Initialize a newly created completion request based on the given arguments.
    */
-  DartCompletionRequestImpl(
-      CompletionRequest request, this.unit, this.isResolved, this.target)
+  DartCompletionRequestImpl(CompletionRequest request, this.parsedTarget)
       : super(request.context, request.resourceProvider, request.source,
             request.offset);
+
+  @override
+  Future<CompletionTarget> get resolvedDeclarationTarget {

[Brian Wilkerson, 2015/10/19 23:15:46]

Consider making this an async function body.

[danrubel, 2015/10/20 00:11:17]

Good idea. It's now easier to read.

+    return (context as AnalysisContextImpl)
+        .computeResolvedCompilationUnitAsync2(source, LIBRARY_ELEMENT1)
+        .then((LibraryElement libraryElement) {
+      return (context as AnalysisContextImpl)
+          .computeResolvedCompilationUnitAsync2(
+              new LibrarySpecificUnit(libraryElement.source, source),
+              RESOLVED_UNIT3);
+    }).then((CompilationUnit resolvedUnit) {
+      return new CompletionTarget.forOffset(resolvedUnit, offset);
+    });
+  }
 }