refactor and cleanup code completion

pkg/analysis_services/lib/src/completion/local_computer.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.computer.dart.local;
 
 import 'dart:async';
 
-import 'package:analysis_services/completion/completion_computer.dart';
 import 'package:analysis_services/completion/completion_suggestion.dart';
+import 'package:analysis_services/src/completion/dart_completion_manager.dart';
 import 'package:analyzer/src/generated/ast.dart';
 
 /**
  * A computer for calculating `completion.getSuggestions` request results
  * for the local library in which the completion is requested.
  */
-class LocalComputer extends CompletionComputer {
+class LocalComputer extends DartCompletionComputer {
 
   @override
-  bool computeFast(CompilationUnit unit, AstNode node,
-      List<CompletionSuggestion> suggestions) {
+  bool computeFast(DartCompletionRequest request) {
 
     // Find the specific child [AstNode] that contains the completion offset
     // and collect suggestions starting with that node
-    if (node != null) {
-      node.accept(new _LocalVisitor(offset, suggestions));
-    }
+    request.node.accept(new _LocalVisitor(request));
 
     // If the unit is not a part and does not reference any parts
     // then work is complete
-    return !unit.directives.any(
+    return !request.unit.directives.any(
         (Directive directive) =>
             directive is PartOfDirective || directive is PartDirective);
   }
 
   @override
-  Future<bool> computeFull(CompilationUnit unit, AstNode node,
-      List<CompletionSuggestion> suggestions) {
+  Future<bool> computeFull(DartCompletionRequest request) {
     // TODO: implement computeFull
     // include results from part files that are included in the library
     return new Future.value(false);
   }
 }
 
 /**
  * A visitor for collecting suggestions from the most specific child [AstNode]
  * that contains the completion offset to the [CompilationUnit].
  */
 class _LocalVisitor extends GeneralizingAstVisitor<dynamic> {
-  final int offset;
-  final List<CompletionSuggestion> suggestions;
+  final DartCompletionRequest request;
 
-  _LocalVisitor(this.offset, this.suggestions);
+  _LocalVisitor(this.request);
 
-  void addSuggestion(SimpleIdentifier id, CompletionSuggestionKind kind) {
-    if (id != null) {
-      String completion = id.name;
-      if (completion != null && completion.length > 0) {
-        suggestions.add(
-            new CompletionSuggestion(
-                kind,
-                CompletionRelevance.DEFAULT,
-                completion,
-                completion.length,
-                0,
-                false,
-                false));
-      }
-    }
-  }
-
-  void addSuggestions(VariableDeclarationList variables,
-      CompletionSuggestionKind kind) {
-    variables.variables.forEach((VariableDeclaration varDecl) {
-      addSuggestion(varDecl.name, kind);
-    });
-  }
-
+  @override
   visitBlock(Block node) {
     node.statements.forEach((Statement stmt) {
-      if (stmt.offset < offset) {
+      if (stmt.offset < request.offset) {
         if (stmt is LabeledStatement) {
           stmt.labels.forEach((Label label) {
-//            addSuggestion(label.label, CompletionSuggestionKind.LABEL);
+//            _addSuggestion(label.label, CompletionSuggestionKind.LABEL);
           });
         } else if (stmt is VariableDeclarationStatement) {
           stmt.variables.variables.forEach((VariableDeclaration varDecl) {
-            if (varDecl.end < offset) {
-              addSuggestion(
+            if (varDecl.end < request.offset) {
+              _addSuggestion(
                   varDecl.name,
                   CompletionSuggestionKind.LOCAL_VARIABLE);
             }
           });
         }
       }
     });
     visitNode(node);
   }
 
+  @override
   visitCatchClause(CatchClause node) {
-    addSuggestion(node.exceptionParameter, CompletionSuggestionKind.PARAMETER);
-    addSuggestion(node.stackTraceParameter, CompletionSuggestionKind.PARAMETER);
+    _addSuggestion(node.exceptionParameter, CompletionSuggestionKind.PARAMETER);
+    _addSuggestion(node.stackTraceParameter, CompletionSuggestionKind.PARAMETER);
     visitNode(node);
   }
 
+  @override
   visitClassDeclaration(ClassDeclaration node) {
     node.members.forEach((ClassMember classMbr) {
       if (classMbr is FieldDeclaration) {
-        addSuggestions(classMbr.fields, CompletionSuggestionKind.FIELD);
+        _addSuggestions(classMbr.fields, CompletionSuggestionKind.FIELD);
       } else if (classMbr is MethodDeclaration) {
-        addSuggestion(classMbr.name, CompletionSuggestionKind.METHOD_NAME);
+        _addSuggestion(classMbr.name, CompletionSuggestionKind.METHOD_NAME);
       }
     });
     visitNode(node);
   }
 
+  @override
   visitCompilationUnit(CompilationUnit node) {
     node.directives.forEach((Directive directive) {
       if (directive is ImportDirective) {
-        addSuggestion(
+        _addSuggestion(
             directive.prefix,
             CompletionSuggestionKind.LIBRARY_PREFIX);
       }
     });
     node.declarations.forEach((Declaration declaration) {
       if (declaration is ClassDeclaration) {
-        addSuggestion(declaration.name, CompletionSuggestionKind.CLASS);
+        _addSuggestion(declaration.name, CompletionSuggestionKind.CLASS);
       } else if (declaration is EnumDeclaration) {
-//        addSuggestion(d.name, CompletionSuggestionKind.ENUM);
+//        _addSuggestion(d.name, CompletionSuggestionKind.ENUM);
       } else if (declaration is FunctionDeclaration) {
-        addSuggestion(declaration.name, CompletionSuggestionKind.FUNCTION);
+        _addSuggestion(declaration.name, CompletionSuggestionKind.FUNCTION);
       } else if (declaration is TopLevelVariableDeclaration) {
-        addSuggestions(
+        _addSuggestions(
             declaration.variables,
             CompletionSuggestionKind.TOP_LEVEL_VARIABLE);
       } else if (declaration is ClassTypeAlias) {
-        addSuggestion(declaration.name, CompletionSuggestionKind.CLASS_ALIAS);
+        _addSuggestion(declaration.name, CompletionSuggestionKind.CLASS_ALIAS);
       } else if (declaration is FunctionTypeAlias) {
-        addSuggestion(
+        _addSuggestion(
             declaration.name,
             CompletionSuggestionKind.FUNCTION_TYPE_ALIAS);
       }
     });
   }
 
+  @override
   visitForEachStatement(ForEachStatement node) {
-    addSuggestion(node.identifier, CompletionSuggestionKind.LOCAL_VARIABLE);
+    _addSuggestion(node.identifier, CompletionSuggestionKind.LOCAL_VARIABLE);
     visitNode(node);
   }
 
+  @override
   visitForStatement(ForStatement node) {
-    addSuggestions(node.variables, CompletionSuggestionKind.LOCAL_VARIABLE);
+    _addSuggestions(node.variables, CompletionSuggestionKind.LOCAL_VARIABLE);
     visitNode(node);
   }
 
+  @override
   visitFunctionDeclaration(FunctionDeclaration node) {
     // This is added by the compilation unit containing it
-    //addSuggestion(node.name, CompletionSuggestionKind.FUNCTION);
+    //_addSuggestion(node.name, CompletionSuggestionKind.FUNCTION);
     visitNode(node);
   }
 
+  @override
   visitFunctionExpression(FunctionExpression node) {
     node.parameters.parameters.forEach((FormalParameter param) {
-      addSuggestion(param.identifier, CompletionSuggestionKind.PARAMETER);
+      _addSuggestion(param.identifier, CompletionSuggestionKind.PARAMETER);
     });
     visitNode(node);
   }
 
+  @override
   visitMethodDeclaration(MethodDeclaration node) {
     node.parameters.parameters.forEach((FormalParameter param) {
       if (param.identifier != null) {
-        addSuggestion(param.identifier, CompletionSuggestionKind.PARAMETER);
+        _addSuggestion(param.identifier, CompletionSuggestionKind.PARAMETER);
       }
     });
     visitNode(node);
   }
 
+  @override
   visitNode(AstNode node) {
     node.parent.accept(this);
   }
 
+  @override
   visitVariableDeclaration(VariableDeclaration node) {
     // Do not add suggestions if editing the name in a var declaration
     SimpleIdentifier name = node.name;
-    if (name == null || name.offset < offset || offset > name.end) {
+    if (name == null ||
+        name.offset < request.offset ||
+        request.offset > name.end) {
       visitNode(node);
     }
   }
+
+  void _addSuggestion(SimpleIdentifier id, CompletionSuggestionKind kind) {
+    if (id != null) {
+      String completion = id.name;
+      if (completion != null && completion.length > 0) {
+        request.suggestions.add(
+            new CompletionSuggestion(
+                kind,
+                CompletionRelevance.DEFAULT,
+                completion,
+                completion.length,
+                0,
+                false,
+                false));
+      }
+    }
+  }
+
+  void _addSuggestions(VariableDeclarationList variables,
+      CompletionSuggestionKind kind) {
+    variables.variables.forEach((VariableDeclaration varDecl) {
+      _addSuggestion(varDecl.name, kind);
+    });
+  }
 }