Add an integration test for analysis.occurrences.

pkg/analysis_server/test/integration/analysis/occurrences_test.dart

+// Copyright (c) 2014, 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 test.integration.analysis.occurrences;
+
+import 'package:analysis_testing/reflective_tests.dart';
+import 'package:unittest/unittest.dart';
+
+import '../integration_tests.dart';
+
+@ReflectiveTestCase()
+class Test extends AbstractAnalysisServerIntegrationTest {
+  test_occurrences() {
+    String pathname = sourcePath('test.dart');
+    String text =
+        r'''
+main() {
+  int sum = 0;
+  for (int i = 0; i < 10; i++) {
+    for (int j = 0; j < i; j++) {
+      sum += j;
+    }
+  }
+  print(sum);
+}
+''';
+    writeFile(pathname, text);
+    standardAnalysisSetup();
+    sendAnalysisSetSubscriptions({
+      'OCCURRENCES': [pathname]
+    });
+    List occurrences;
+    onAnalysisOccurrences.listen((params) {
+      expect(params['file'], equals(pathname));
+      occurrences = params['occurrences'];
+    });
+    return analysisFinished.then((_) {
+      expect(currentAnalysisErrors[pathname], isEmpty);
+      Set<int> findOffsets(String elementName) {
+        for (Map occurrence in occurrences) {
+          if (occurrence['element']['name'] == elementName) {
+            return occurrence['offsets'].toSet();
+          }
+        }
+        fail('No element found matching $elementName');
+        return null;
+      }
+      void check(String elementName, Iterable<String> expectedOccurrences) {
+        Set<int> expectedOffsets = expectedOccurrences.map((String substring) =>
+            text.indexOf(substring)).toSet();
+        Set<int> foundOffsets = findOffsets(elementName);
+        expect(foundOffsets, equals(expectedOffsets));
+      }
+      check('i', ['i = 0', 'i < 10', 'i++', 'i;']);
+      check('j', ['j = 0', 'j < i', 'j++', 'j;']);
+      check('sum', ['sum = 0', 'sum +=', 'sum)']);
+    });
+  }
+}
+
+main() {
+  runReflectiveTests(Test);
+}