Fix cache corruption in incremental resolver

pkg/analyzer/lib/src/context/cache.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.cache;
 
 import 'dart:async';
 import 'dart:collection';
 
+import 'package:analyzer/src/dart/element/element.dart'
+    show ElementImpl, Modifier;
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_collection.dart';
 import 'package:analyzer/src/task/model.dart';
 import 'package:analyzer/task/model.dart';
 
 /**
  * Return `true` if the given [target] is a priority one.
  */
@@ skipping 212 matching lines @@
    */
   CacheEntry remove(AnalysisTarget target) {
     int count = _partitions.length;
     for (int i = 0; i < count; i++) {
       CachePartition partition = _partitions[i];
       if (partition.isResponsibleFor(target)) {
         if (_TRACE_CHANGES) {
           AnalysisEngine.instance.logger
               .logInformation('Removed the cache entry for $target.');
         }
-        return partition.remove(target);
+        var entry = partition.remove(target);

[Brian Wilkerson, 2016/02/16 15:10:48]

Missing type

[skybrian, 2016/02/17 01:23:41]

Done.

+        if (entry != null) {
+          entry.dispose();
+          if (target is ElementImpl) {
+            target.setModifier(Modifier.CACHE_KEY, false);

[Brian Wilkerson, 2016/02/16 15:10:48]

Won't `dispose` have already cleared the flag?

[skybrian, 2016/02/17 01:23:41]

Fixed. (Yes, this was left over from debugging.)

+          }
+        }
+        return entry;
       }
     }
     return null;
   }
 
   /**
    * Return the number of targets that are mapped to cache entries.
    */
   int size() {
     int size = 0;
@@ skipping 47 matching lines @@
    * A bit-encoding of boolean flags associated with this entry's target.
    */
   int _flags = 0;
 
   /**
    * A table mapping result descriptors to the cached values of those results.
    */
   Map<ResultDescriptor, ResultData> _resultMap =
       new HashMap<ResultDescriptor, ResultData>();
 
-  CacheEntry(this.target);
+  CacheEntry(this.target) {
+    if (target is ElementImpl) {
+      (target as ElementImpl).setModifier(Modifier.CACHE_KEY, true);

[skybrian, 2016/02/16 07:11:06]

Since target is a field, the extra cast is necessary to avoid a warning.

+    }
+  }
 
   /**
    * The exception that caused one or more values to have a state of
    * [CacheState.ERROR].
    */
   CaughtException get exception => _exception;
 
   /**
    * Return `true` if the source was explicitly added to the context or `false`
    * if the source was implicitly added because it was referenced by another
@@ skipping 22 matching lines @@
     _resultMap.forEach((descriptor, data) {
       TargetedResult result = new TargetedResult(target, descriptor);
       for (TargetedResult dependedOnResult in data.dependedOnResults) {
         ResultData dependedOnData = _partition._getDataFor(dependedOnResult);
         if (dependedOnData != null) {
           dependedOnData.dependentResults.remove(result);
         }
       }
     });
     _resultMap.clear();
+    if (target is ElementImpl) {
+      (target as ElementImpl).setModifier(Modifier.CACHE_KEY, false);
+    }
   }
 
   /**
    * Fix the state of the [exception] to match the current state of the entry.
    */
   void fixExceptionState() {
     if (!hasErrorState()) {
       _exception = null;
     }
   }
@@ skipping 14 matching lines @@
     if (data == null) {
       return CacheState.INVALID;
     }
     return data.state;
   }
 
   /**
    * Return the value of the result represented by the given [descriptor], or
    * the default value for the result if this entry does not have a valid value.
    */
-  dynamic /*=V*/ getValue /*<V>*/ (ResultDescriptor /*<V>*/ descriptor) {
+  dynamic/*=V*/ getValue/*<V>*/(ResultDescriptor/*<V>*/ descriptor) {
     ResultData data = _resultMap[descriptor];
     if (data == null) {
       return descriptor.defaultValue;
     }
     if (_partition != null) {
       _partition.resultAccessed(target, descriptor);
     }
     return data.value;
   }
 
@@ skipping 77 matching lines @@
         //
         data.value = descriptor.defaultValue;
       }
     }
   }
 
   /**
    * Set the value of the result represented by the given [descriptor] to the
    * given [value].
    */
-  void setValue /*<V>*/ (ResultDescriptor /*<V>*/ descriptor,
-      dynamic /*=V*/ value, List<TargetedResult> dependedOn) {
+  void setValue/*<V>*/(ResultDescriptor/*<V>*/ descriptor, dynamic/*=V*/ value,
+      List<TargetedResult> dependedOn) {
 //    {
 //      String valueStr = '$value';
 //      if (valueStr.length > 20) {
 //        valueStr = valueStr.substring(0, 20) + '...';
 //      }
 //      valueStr = valueStr.replaceAll('\n', '\\n');
 //      print(
 //          'setValue $descriptor for $target value=$valueStr $dependedOn=$dependedOn');
 //    }
     _validateStateChange(descriptor, CacheState.VALID);
@@ skipping 77 matching lines @@
     for (TargetedResult dependedOnResult in thisData.dependedOnResults) {
       ResultData data = _partition._getDataFor(dependedOnResult);
       if (data != null && deltaResult != DeltaResult.KEEP_CONTINUE) {
         data.dependentResults.remove(thisResult);
       }
     }
     // Invalidate results that depend on this result.
     _invalidateDependentResults(id, thisData, delta, level + 1);
     // If empty and not explicitly added, remove the entry altogether.
     if (_resultMap.isEmpty && !explicitlyAdded) {
-      _partition.entryMap.remove(target);
+      var entry = _partition.entryMap.remove(target);

[Brian Wilkerson, 2016/02/16 15:10:48]

Missing type

[skybrian, 2016/02/17 01:23:41]

Done.

+      if (entry != null) {
+        entry.dispose();
+        if (target is ElementImpl) {
+          (target as ElementImpl).setModifier(Modifier.CACHE_KEY, false);
+        }
+      }
       _partition._removeIfSource(target);
     }
     // Notify controller.
     _partition.onResultInvalidated
         .add(new InvalidatedResult(this, descriptor, thisData.value));
   }
 
   /**
    * Invalidates all the results of this entry, with propagation.
    */
@@ skipping 657 matching lines @@
   void resultAccessed(TargetedResult result) {}
 
   @override
   List<TargetedResult> resultStored(TargetedResult newResult, newValue) {
     return TargetedResult.EMPTY_LIST;
   }
 
   @override
   void targetRemoved(AnalysisTarget target) {}
 }