Add OCCURRENCES_CONTRIBUTOR_EXTENSION_POINT_ID.

pkg/analysis_server/lib/src/domains/analysis/occurrences_dart.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file

[Brian Wilkerson, 2015/09/11 20:26:24]

2015

+// 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 domains.analysis.occurrences_dart;
+
+import 'package:analysis_server/analysis/occurrences_core.dart';
+import 'package:analysis_server/src/protocol_server.dart' as protocol;
+import 'package:analyzer/src/generated/ast.dart';
+import 'package:analyzer/src/generated/element.dart';
+import 'package:analyzer/src/generated/engine.dart';
+import 'package:analyzer/src/generated/source.dart';
+
+/**
+ * A computer for occurrences in a Dart [CompilationUnit].
+ */
+class DartOccurrencesComputer implements OccurrencesContributor {
+  @override
+  void computeOccurrences(
+      OccurrencesCollector collector, AnalysisContext context, Source source) {
+    List<Source> libraries = context.getLibrariesContaining(source);
+    if (libraries.isNotEmpty) {
+      CompilationUnit unit =
+          context.getResolvedCompilationUnit2(source, libraries.first);
+      if (unit != null) {
+        _DartUnitOccurrencesComputerVisitor visitor =
+            new _DartUnitOccurrencesComputerVisitor();
+        unit.accept(visitor);
+        visitor.elementsOffsets.forEach((engineElement, offsets) {
+          int length = engineElement.displayName.length;
+          protocol.Element serverElement =
+              protocol.newElement_fromEngine(engineElement);
+          protocol.Occurrences occurrences =
+              new protocol.Occurrences(serverElement, offsets, length);
+          collector.addOccurrences(occurrences);
+        });
+      }
+    }
+  }
+}
+
+class _DartUnitOccurrencesComputerVisitor extends RecursiveAstVisitor {
+  final Map<Element, List<int>> elementsOffsets = <Element, List<int>>{};
+
+  @override
+  visitSimpleIdentifier(SimpleIdentifier node) {
+    Element element = node.bestElement;
+    if (element != null) {
+      _addOccurrence(element, node.offset);
+    }
+    return super.visitSimpleIdentifier(node);
+  }
+
+  void _addOccurrence(Element element, int offset) {
+    element = _canonicalizeElement(element);
+    if (element == null || element == DynamicElementImpl.instance) {
+      return;
+    }
+    List<int> offsets = elementsOffsets[element];
+    if (offsets == null) {
+      offsets = <int>[];
+      elementsOffsets[element] = offsets;
+    }
+    offsets.add(offset);
+  }
+
+  Element _canonicalizeElement(Element element) {
+    if (element is FieldFormalParameterElement) {
+      element = (element as FieldFormalParameterElement).field;
+    }
+    if (element is PropertyAccessorElement) {
+      element = (element as PropertyAccessorElement).variable;
+    }
+    if (element is Member) {
+      element = (element as Member).baseElement;
+    }
+    return element;
+  }
+}