process sorter analysis request(s)

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

Index: pkg/analysis_server/lib/src/services/completion/dart_completion_manager.dart
diff --git a/pkg/analysis_server/lib/src/services/completion/dart_completion_manager.dart b/pkg/analysis_server/lib/src/services/completion/dart_completion_manager.dart
index 0a23c17499274fad7532f35080057071c0ff8b61..2edb62a95be4aee106e2e62c3cc70585b0c4fdb4 100644
--- a/pkg/analysis_server/lib/src/services/completion/dart_completion_manager.dart
+++ b/pkg/analysis_server/lib/src/services/completion/dart_completion_manager.dart
@@ -9,7 +9,7 @@ import 'dart:async';
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/provisional/completion/completion_core.dart'
-    show CompletionRequest;
+    show AnalysisRequest, CompletionRequest;
 import 'package:analysis_server/src/provisional/completion/completion_dart.dart'
     as newApi;
 import 'package:analysis_server/src/provisional/completion/dart/completion_target.dart';
@@ -27,10 +27,14 @@ import 'package:analysis_server/src/services/completion/prefixed_element_contrib
 import 'package:analysis_server/src/services/completion/uri_contributor.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/src/cancelable_future.dart';
+import 'package:analyzer/src/context/context.dart'
+    show AnalysisFutureHelper, AnalysisContextImpl;
 import 'package:analyzer/src/generated/ast.dart';
-import 'package:analyzer/src/generated/engine.dart';
+import 'package:analyzer/src/generated/engine.dart' hide AnalysisContextImpl;
 import 'package:analyzer/src/generated/scanner.dart';
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/task/model.dart';
 
 const int DART_RELEVANCE_COMMON_USAGE = 1200;
 const int DART_RELEVANCE_DEFAULT = 1000;
@@ -181,11 +185,11 @@ class DartCompletionManager extends CompletionManager {
           return c.computeFast(request);
         });
       });
-      // TODO(danrubel) Process the AnalysisRequest returned by the
-      // contribution sorter. At this point, the target unit has been fully
-      // resolved, thus no need for additional resolution, but in the future...
-      contributionSorter.sort(request, request.suggestions);
-
+      _processAnalysisRequest(request,
+          contributionSorter.sort(request, request.suggestions));
+      // TODO (danrubel) if request is obsolete
+      // (processAnalysisRequest returns false)
+      // then send empty results
       if (todo.isEmpty) {
         sendResults(request, todo.isEmpty);

[Brian Wilkerson, 2015/11/17 15:11:37]

If I understand correctly, this will only work if the `sort` method returns
`null`. If it actually needed additional results we would end up sending the
results before the results could be computed. If that's true, we should fail
quickly until we've implemented the rest of the support for it.

And this will necessitate that every method that could eventually invoke this
method be made asynchronous. Is it really worth while in order to allow sorting
to request additional results? Would it be better / possible to allow the
suggestions to capture enough information that we don't need more data in order
to sort them?

[danrubel, 2015/11/17 18:35:44]

Correct. Per discussion, I will be adding support for this over the next several
CLs as I incrementally convert all contributors to the new API.
The _processAnalysisRequest method will be used to process every analysis
request for every contributor. Requests for analysis from the sorter will be
handled in the same way after contributors. In addition, the computeFast and
computeFull methods will be combined into a single compute suggestions method.
Given this, I think supporting the sorter in this way will add only minimal
complexity.

       }
@@ -225,11 +229,11 @@ class DartCompletionManager extends CompletionManager {
               performance.logElapseTime(completeTag);
               bool last = --count == 0;
               if (changed || last) {
-                // TODO(danrubel) Process the AnalysisRequest returned by the
-                // contribution sorter. At this point, the target unit has been
-                // fully resolved, thus no need for additional resolution,
-                // but in the future...
-                contributionSorter.sort(request, request.suggestions);
+                _processAnalysisRequest(request,
+                    contributionSorter.sort(request, request.suggestions));
+                // TODO (danrubel) if request is obsolete
+                // (processAnalysisRequest returns false)
+                // then send empty results
                 sendResults(request, last);
               }
             });
@@ -287,6 +291,38 @@ class DartCompletionManager extends CompletionManager {
       return null;
     }, test: (e) => e is AnalysisNotScheduledError);
   }
+
+  /**
+   * Process the analysis [analysis] and any subsequent requests.
+   * Return a [Future] that returns `true`
+   * once all analysis requests have been processed
+   * or `false` if the original completion request is obsolete
+   * and processing requests was terminated before finished.
+   */
+  Future<bool> _processAnalysisRequest(
+      CompletionRequest request, AnalysisRequest analysis) {
+    // Return if no additional analysis is necessary
+    if (analysis == null) {
+      return new Future.value(true);
+    }
+
+    // Check to see if the result is already cached
+    var cachedValue = context.getResult(analysis.target, analysis.descriptor);
+    if (cachedValue != null) {
+      return _processAnalysisRequest(
+          request, analysis.callback(request, cachedValue));
+    }
+
+    // TODO (danrubel) determine when completion request is obsolete
+    // and analysis should be terminated before requesting additional analysis
+
+    // Request additional analysis
+    return new AnalysisFutureHelper((context as AnalysisContextImpl),
+        analysis.target, analysis.descriptor).computeAsync().then((value) {
+      return _processAnalysisRequest(
+          request, analysis.callback(request, cachedValue));
+    });
+  }
 }
 
 /**