Test for duplicate referenced in index and clean up super types.

pkg/analyzer/test/src/summary/index_unit_test.dart

 // Copyright (c) 2016, 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.
 
 import 'dart:convert';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/idl.dart';
@@ skipping 504 matching lines @@
 ''');
     Element element = findElement('A');
     assertThat(element).isReferencedAt('A myVariable');
   }
 
   /**
    * Asserts that [unitIndex] has an item with the expected properties.
    */
   void _assertHasRelation(
       Element element,
-      IndexRelationKind expectedRelationship,
+      IndexRelationKind expectedRelationKind,
       ExpectedLocation expectedLocation) {
     int elementId = _findElementId(element);
+    int matchIndex;
     for (int i = 0; i < unitIndex.locationOffsets.length; i++) {
       if (unitIndex.elements[i] == elementId &&
           unitIndex.locationOffsets[i] == expectedLocation.offset &&
           unitIndex.locationLengths[i] == expectedLocation.length) {
-        // TODO(scheglov) continue looking to check that only one usage at one
-        // location, e.g. no both 'reference' and 'invocation'.
-        return;
+        if (matchIndex == null) {
+          matchIndex = i;
+        } else {
+          _failWithIndexDump('more then one ($matchIndex and $i) match found\n'
+              '$element at $expectedLocation');
+        }
       }
     }
+    if (matchIndex != null &&
+        unitIndex.kinds[matchIndex] == expectedRelationKind) {
+      return;
+    }
     _failWithIndexDump(
-        'not found\n$element $expectedRelationship at $expectedLocation');
+        'not found\n$element $expectedRelationKind at $expectedLocation');
   }
 
   ExpectedLocation _expectedLocation(String search,
       {int length, bool isQualified: false, bool isResolved: true}) {
     int offset = findOffset(search);
     if (length == null) {
       length = getLeadingIdentifierLength(search);
     }
     return new ExpectedLocation(
         testUnitElement, offset, length, isQualified, isResolved);
   }
 
   void _failWithIndexDump(String msg) {
     String packageIndexJsonString =
         new JsonEncoder.withIndent('  ').convert(packageIndex.toJson());
     fail('$msg in\n' + packageIndexJsonString);
   }
 
   /**
    * Return the [element] identifier in [packageIndex] or fail.
    */
   int _findElementId(Element element) {
     int elementUnitId = _getElementUnitId(element);
     int offset = element.nameOffset;
     if (element is LibraryElement || element is CompilationUnitElement) {
       offset = 0;
     }
-    IndexSyntheticElementKind kind = PackageIndexAssembler.getIndexElementKind(element);
+    IndexSyntheticElementKind kind =
+        PackageIndexAssembler.getIndexElementKind(element);
     for (int elementId = 0;
         elementId < packageIndex.elementUnits.length;
         elementId++) {
       if (packageIndex.elementUnits[elementId] == elementUnitId &&
           packageIndex.elementOffsets[elementId] == offset &&
           packageIndex.elementKinds[elementId] == kind) {
         return elementId;
       }
     }
     _failWithIndexDump('Element $element is not referenced');
@@ skipping 62 matching lines @@
     test._assertHasRelation(element, IndexRelationKind.IS_MIXED_IN_BY,
         test._expectedLocation(search, length: length));
   }
 
   void isReferencedAt(String search, {int length, bool qualified: false}) {
     // TODO(scheglov) use 'qualified'
     test._assertHasRelation(element, IndexRelationKind.IS_REFERENCED_BY,
         test._expectedLocation(search, length: length));
   }
 }