fix ENUM_CONSTANT suggestions

pkg/analysis_server/lib/src/protocol_server.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 protocol.server;
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart'
     as engine;
 import 'package:analyzer/src/generated/ast.dart' as engine;
@@ skipping 69 matching lines @@
 }
 
 /**
  * Construct based on a value from the analyzer engine.
  */
 Element newElement_fromEngine(engine.Element element) {
   String name = element.displayName;
   String elementTypeParameters = _getTypeParametersString(element);
   String elementParameters = _getParametersString(element);
   String elementReturnType = _getReturnTypeString(element);
-  ElementKind kind = newElementKind_fromEngine(element.kind);
-  // TODO(danrubel) this check should be in newElementKind_fromEngine
-  if (element is engine.ClassElement && element.isEnum) {
-    kind = ElementKind.ENUM;
-  }
-  return new Element(kind, name, Element
-          .makeFlags(
-              isPrivate: element.isPrivate,
-              isDeprecated: element.isDeprecated,
-              isAbstract: _isAbstract(element),
-              isConst: _isConst(element),
-              isFinal: _isFinal(element),
-              isStatic: _isStatic(element)),
+  ElementKind kind = newElementKind_fromEngineElement(element);
+  return new Element(kind, name, Element.makeFlags(
+          isPrivate: element.isPrivate,
+          isDeprecated: element.isDeprecated,
+          isAbstract: _isAbstract(element),
+          isConst: _isConst(element),
+          isFinal: _isFinal(element),
+          isStatic: _isStatic(element)),
       location: newLocation_fromElement(element),
       typeParameters: elementTypeParameters,
       parameters: elementParameters,
       returnType: elementReturnType);
 }
 
 /**
  * Construct based on a value from the analyzer engine.
+ * This does not take into account that 
+ * instances of ClassElement can be an enum and
+ * instances of FieldElement can be an enum constant.
+ * Use [newElementKind_fromEngineElement] where possible.
  */
 ElementKind newElementKind_fromEngine(engine.ElementKind kind) {

[scheglov, 2015/06/04 21:55:37]

This function is always invoked for some "elementInstance.kind" in production,
so maybe we could merge it with newElementKind_fromEngineElement().

[danrubel, 2015/06/04 22:00:08]

There are a number of tests for this method which I did not want to touch for
this CL, but yes, that would be a good next step.

   if (kind == engine.ElementKind.CLASS) {
-    // TODO(danrubel) check if element.isEnum and return ElementKind.ENUM
     return ElementKind.CLASS;
   }
   if (kind == engine.ElementKind.COMPILATION_UNIT) {
     return ElementKind.COMPILATION_UNIT;
   }
   if (kind == engine.ElementKind.CONSTRUCTOR) {
     return ElementKind.CONSTRUCTOR;
   }
   if (kind == engine.ElementKind.FIELD) {
     return ElementKind.FIELD;
@@ skipping 31 matching lines @@
   if (kind == engine.ElementKind.TOP_LEVEL_VARIABLE) {
     return ElementKind.TOP_LEVEL_VARIABLE;
   }
   if (kind == engine.ElementKind.TYPE_PARAMETER) {
     return ElementKind.TYPE_PARAMETER;
   }
   return ElementKind.UNKNOWN;
 }
 
 /**
+ * Construct based on a value from the analyzer engine.
+ */
+ElementKind newElementKind_fromEngineElement(engine.Element element) {
+  if (element is engine.ClassElement && element.isEnum) {
+    return ElementKind.ENUM;
+  }
+  if (element is engine.FieldElement && element.isEnumConstant &&
+      // MyEnum.values and MyEnum.one.index return isEnumConstant = true
+      // so these additional checks are necessary.
+      // TODO(danrubel) MyEnum.values is constant, but is a list
+      // so should it return isEnumConstant = true?
+      // MyEnum.one.index is final but *not* constant
+      // so should it return isEnumConstant = true?
+      // Or should we return ElementKind.ENUM_CONSTANT here
+      // in either or both of these cases?
+      element.type != null &&
+      element.type.element == element.enclosingElement) {
+    return ElementKind.ENUM_CONSTANT;
+  }
+  return newElementKind_fromEngine(element.kind);
+}
+
+/**
  * Create a Location based on an [engine.Element].
  */
 Location newLocation_fromElement(engine.Element element) {
   engine.AnalysisContext context = element.context;
   engine.Source source = element.source;
   if (context == null || source == null) {
     return null;
   }
   String name = element.displayName;
   int offset = element.nameOffset;
@@ skipping 240 matching lines @@
     if (lineInfo != null) {
       engine.LineInfo_Location offsetLocation =
           lineInfo.getLocation(range.offset);
       startLine = offsetLocation.lineNumber;
       startColumn = offsetLocation.columnNumber;
     }
   }
   return new Location(
       source.fullName, range.offset, range.length, startLine, startColumn);
 }