Get computeError working

pkg/analyzer/lib/src/context/context.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 analyzer.src.context.context;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/src/cancelable_future.dart';
@@ skipping 744 matching lines @@
     } catch (exception) {
       // If the location cannot be decoded for some reason then the underlying
       // cause should have been logged already and we can fall though to return
       // null.
     }
     return null;
   }
 
   @override
   AnalysisErrorInfo getErrors(Source source) {
-    List<AnalysisError> errors = _getResult(source, DART_ERRORS);
+    // TODO(brianwilkerson) Figure out how to implement this cleanly. The
+    // problem is that _getResult doesn't know to go into the individual inputs
+    // for the task to get their values for tasks that are just merging other
+    // result values. Therefore, if some, but not all, of the error lists have
+    // been computed, no errors will be returned by it.
+    List<List<AnalysisError>> errorLists = <List<AnalysisError>>[];
+    errorLists.add(_getResult(source, BUILD_DIRECTIVES_ERRORS));
+    errorLists.add(_getResult(source, BUILD_LIBRARY_ERRORS));
+    errorLists.add(_getResult(source, PARSE_ERRORS));
+    errorLists.add(_getResult(source, SCAN_ERRORS));
+    for (Source library in getLibrariesContaining(source)) {
+      LibrarySpecificUnit unit = new LibrarySpecificUnit(library, source);
+      errorLists.add(_getResult(unit, BUILD_FUNCTION_TYPE_ALIASES_ERRORS));
+      errorLists.add(_getResult(unit, HINTS));
+      errorLists.add(_getResult(unit, RESOLVE_REFERENCES_ERRORS));
+      errorLists.add(_getResult(unit, RESOLVE_TYPE_NAMES_ERRORS));
+      errorLists.add(_getResult(unit, VERIFY_ERRORS));
+    }
     LineInfo lineInfo = _getResult(source, LINE_INFO);
-    return new AnalysisErrorInfoImpl(errors, lineInfo);
+    return new AnalysisErrorInfoImpl(
+        AnalysisError.mergeLists(errorLists), lineInfo);
   }
 
   @override
   HtmlElement getHtmlElement(Source source) {
     // TODO(brianwilkerson) Implement this.
 //    SourceEntry sourceEntry = getReadableSourceEntryOrNull(source);
 //    if (sourceEntry is HtmlEntry) {
 //      return sourceEntry.getValue(HtmlEntry.ELEMENT);
 //    }
     return null;
@@ skipping 1344 matching lines @@
     PendingFuture pendingFuture =
         new PendingFuture<T>(_context, target, computeValue);
     if (!pendingFuture.evaluate(entry)) {
       _context._pendingFutureTargets
           .putIfAbsent(target, () => <PendingFuture>[])
           .add(pendingFuture);
     }
     return pendingFuture.future;
   }
 }