extract LabelContributor from local reference contributor

pkg/analysis_server/lib/src/services/completion/local_reference_contributor.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 services.completion.contributor.dart.local;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/protocol/protocol.dart' as protocol
     show Element, ElementKind;
@@ skipping 23 matching lines @@
     // Collect suggestions from the specific child [AstNode] that contains
     // the completion offset and all of its parents recursively.
     if (!optype.isPrefixed) {
       if (optype.includeReturnValueSuggestions ||
           optype.includeTypeNameSuggestions ||
           optype.includeVoidReturnSuggestions) {
         _LocalVisitor localVisitor =
             new _LocalVisitor(request, request.offset, optype);
         localVisitor.visit(request.target.containingNode);
       }
-      if (optype.includeStatementLabelSuggestions ||
-          optype.includeCaseLabelSuggestions) {
-        _LabelVisitor labelVisitor = new _LabelVisitor(
-            request,
-            optype.includeStatementLabelSuggestions,
-            optype.includeCaseLabelSuggestions);
-        labelVisitor.visit(request.target.containingNode);
-      }
       if (optype.includeConstructorSuggestions) {
         new _ConstructorVisitor(request).visit(request.target.containingNode);
       }
     }
 
     // If target is an argument in an argument list
     // then suggestions may need to be adjusted
     return request.target.argIndex == null;
   }
 
@@ skipping 169 matching lines @@
             }
           }
         }
       }
     }
     return DYNAMIC;
   }
 }
 
 /**
- * A visitor for collecting suggestions for break and continue labels.
- */
-class _LabelVisitor extends LocalDeclarationVisitor {
-  final DartCompletionRequest request;
-
-  /**
-   * True if statement labels should be included as suggestions.
-   */
-  final bool includeStatementLabels;
-
-  /**
-   * True if case labels should be included as suggestions.
-   */
-  final bool includeCaseLabels;
-
-  _LabelVisitor(DartCompletionRequest request, this.includeStatementLabels,
-      this.includeCaseLabels)
-      : super(request.offset),
-        request = request;
-
-  @override
-  void declaredClass(ClassDeclaration declaration) {
-    // ignored
-  }
-
-  @override
-  void declaredClassTypeAlias(ClassTypeAlias declaration) {
-    // ignored
-  }
-
-  @override
-  void declaredField(FieldDeclaration fieldDecl, VariableDeclaration varDecl) {
-    // ignored
-  }
-
-  @override
-  void declaredFunction(FunctionDeclaration declaration) {
-    // ignored
-  }
-
-  @override
-  void declaredFunctionTypeAlias(FunctionTypeAlias declaration) {
-    // ignored
-  }
-
-  @override
-  void declaredLabel(Label label, bool isCaseLabel) {
-    if (isCaseLabel ? includeCaseLabels : includeStatementLabels) {
-      CompletionSuggestion suggestion = _addSuggestion(label.label);
-      if (suggestion != null) {
-        suggestion.element = createElement(
-            request.source, protocol.ElementKind.LABEL, label.label,
-            returnType: NO_RETURN_TYPE);
-      }
-    }
-  }
-
-  @override
-  void declaredLocalVar(SimpleIdentifier name, TypeName type) {
-    // ignored
-  }
-
-  @override
-  void declaredMethod(MethodDeclaration declaration) {
-    // ignored
-  }
-
-  @override
-  void declaredParam(SimpleIdentifier name, TypeName type) {
-    // ignored
-  }
-
-  @override
-  void declaredTopLevelVar(
-      VariableDeclarationList varList, VariableDeclaration varDecl) {
-    // ignored
-  }
-
-  @override
-  void visitFunctionExpression(FunctionExpression node) {
-    // Labels are only accessible within the local function, so stop visiting
-    // once we reach a function boundary.
-    finished();
-  }
-
-  @override
-  void visitMethodDeclaration(MethodDeclaration node) {
-    // Labels are only accessible within the local function, so stop visiting
-    // once we reach a function boundary.
-    finished();
-  }
-
-  CompletionSuggestion _addSuggestion(SimpleIdentifier id) {
-    if (id != null) {
-      String completion = id.name;
-      if (completion != null && completion.length > 0 && completion != '_') {
-        CompletionSuggestion suggestion = new CompletionSuggestion(
-            CompletionSuggestionKind.IDENTIFIER,
-            DART_RELEVANCE_DEFAULT,
-            completion,
-            completion.length,
-            0,
-            false,
-            false);
-        request.addSuggestion(suggestion);
-        return suggestion;
-      }
-    }
-    return null;
-  }
-}
-
-/**
  * A visitor for collecting suggestions from the most specific child [AstNode]
  * that contains the completion offset to the [CompilationUnit].
  */
 class _LocalVisitor extends LocalDeclarationVisitor {
   final DartCompletionRequest request;
   final OpType optype;
   int privateMemberRelevance = DART_RELEVANCE_DEFAULT;
 
   _LocalVisitor(this.request, int offset, this.optype) : super(offset) {
     includeLocalInheritedTypes = !optype.inStaticMethodBody;
@@ skipping 228 matching lines @@
   bool _isVoid(TypeName returnType) {
     if (returnType != null) {
       Identifier id = returnType.name;
       if (id != null && id.name == 'void') {
         return true;
       }
     }
     return false;
   }
 }