convert engine element setter to completion element setter

pkg/analysis_server/test/computer/element_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.computer.element;
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart' as engine;
 import 'package:analyzer/src/generated/source.dart';
@@ skipping 265 matching lines @@
       expect(location.offset, 32);
       expect(location.length, 'myGetter'.length);
       expect(location.startLine, 2);
       expect(location.startColumn, 23);
     }
     expect(element.parameters, '(int a, {String b})');
     expect(element.returnType, 'List<String>');
     expect(element.flags, Element.FLAG_STATIC);
   }
 
+  void test_fromElement_SETTER() {
+    Source source = addSource('/test.dart', '''
+class A {
+  set mySetter(String x) {}
+}''');
+    CompilationUnit unit = resolveLibraryUnit(source);
+    engine.FieldElement engineFieldElement =
+        findElementInUnit(unit, 'mySetter', engine.ElementKind.FIELD);

[Brian Wilkerson, 2014/09/16 22:47:46]

The "engine.ElementKind.FIELD" argument looks strange, both because it's there
and because it isn't "engine.ElementKind.SETTER". But I'm not familiar enough
with these tests to know whether it's a problem.

[danrubel, 2014/09/16 23:12:30]

I was surprised as well, but my current understanding is that the element model
represents the synthetic field updated by the setter, thus the setter is
attached to and accessed via that field.

+    engine.PropertyAccessorElement engineElement = engineFieldElement.setter;
+    // create notification Element
+    Element element = new Element.fromEngine(engineElement);
+    expect(element.kind, ElementKind.SETTER);
+    expect(element.name, 'mySetter');
+    {
+      Location location = element.location;
+      expect(location.file, '/test.dart');
+      expect(location.offset, 16);
+      expect(location.length, 'mySetter'.length);
+      expect(location.startLine, 2);
+      expect(location.startColumn, 7);
+    }
+    expect(element.parameters, '(String x)');
+    expect(element.returnType, isNull);
+    expect(element.flags, 0);
+  }
+
   void test_fromElement_dynamic() {
     var engineElement = engine.DynamicElementImpl.instance;
     // create notification Element
     Element element = new Element.fromEngine(engineElement);
     expect(element.kind, ElementKind.UNKNOWN);
     expect(element.name, 'dynamic');
     expect(element.location, isNull);
     expect(element.parameters, isNull);
     expect(element.returnType, isNull);
     expect(element.flags, 0);
   }
 }