improve keyword suggestions

pkg/analysis_server/lib/src/services/completion/keyword_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.keyword;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
@@ skipping 23 matching lines @@
 class _KeywordVisitor extends GeneralizingAstVisitor {
   final DartCompletionRequest request;
   final Object entity;
 
   _KeywordVisitor(DartCompletionRequest request)
       : this.request = request,
         this.entity = request.target.entity;
 
   @override
   visitBlock(Block node) {
-    if (_isInClassMemberBody(node)) {
-      _addSuggestions([Keyword.SUPER, Keyword.THIS,]);
-    }
-    _addSuggestions([
-      Keyword.ASSERT,
-      Keyword.CASE,
-      Keyword.CONTINUE,
-      Keyword.DO,
-      Keyword.FINAL,
-      Keyword.FOR,
-      Keyword.IF,
-      Keyword.NEW,
-      Keyword.RETHROW,
-      Keyword.RETURN,
-      Keyword.SWITCH,
-      Keyword.THROW,
-      Keyword.TRY,
-      Keyword.VAR,
-      Keyword.VOID,
-      Keyword.WHILE
-    ]);
+    _addStatementKeywords(node);
   }
 
   @override
   visitClassDeclaration(ClassDeclaration node) {
     // Don't suggest class name
     if (entity == node.name) {
       return;
     }
     if (entity == node.rightBracket || entity is ClassMember) {
       _addSuggestions([
@@ skipping 56 matching lines @@
         Keyword.DYNAMIC,
         Keyword.FINAL,
         Keyword.TYPEDEF,
         Keyword.VAR,
         Keyword.VOID
       ], DART_RELEVANCE_HIGH);
     }
   }
 
   @override
+  visitIfStatement(IfStatement node) {
+    if (entity == node.thenStatement) {
+      _addStatementKeywords(node);
+    }
+  }
+
+  @override
   visitImportDirective(ImportDirective node) {
     if (entity == node.asKeyword) {
       if (node.deferredKeyword == null) {
         _addSuggestion(Keyword.DEFERRED, DART_RELEVANCE_HIGH);
       }
     }
     if (entity == node.semicolon || node.combinators.contains(entity)) {
       _addImportDirectiveKeywords(node);
     }
   }
 
-  void _addImportDirectiveKeywords(ImportDirective node) {
-    if (node.asKeyword == null) {
-      _addSuggestion(Keyword.AS, DART_RELEVANCE_HIGH);
-      if (node.deferredKeyword == null) {
-        _addSuggestion(Keyword.DEFERRED, DART_RELEVANCE_HIGH);
-      }
-    }
-  }
-
   void _addClassDeclarationKeywords(ClassDeclaration node) {
     // Very simplistic suggestion because analyzer will warn if
     // the extends / with / implements keywords are out of order
     if (node.extendsClause == null) {
       _addSuggestion(Keyword.EXTENDS, DART_RELEVANCE_HIGH);
     } else if (node.withClause == null) {
       _addSuggestion(Keyword.WITH, DART_RELEVANCE_HIGH);
     }
     if (node.implementsClause == null) {
       _addSuggestion(Keyword.IMPLEMENTS, DART_RELEVANCE_HIGH);
     }
   }
 
+  void _addImportDirectiveKeywords(ImportDirective node) {
+    if (node.asKeyword == null) {
+      _addSuggestion(Keyword.AS, DART_RELEVANCE_HIGH);
+      if (node.deferredKeyword == null) {
+        _addSuggestion(Keyword.DEFERRED, DART_RELEVANCE_HIGH);
+      }
+    }
+  }
+
+  void _addStatementKeywords(AstNode node) {
+    if (_isInClassMemberBody(node)) {
+      _addSuggestions([Keyword.SUPER, Keyword.THIS,]);
+    }
+    _addSuggestions([
+      Keyword.ASSERT,
+      Keyword.CASE,
+      Keyword.CONTINUE,
+      Keyword.DO,
+      Keyword.FINAL,
+      Keyword.FOR,
+      Keyword.IF,
+      Keyword.NEW,
+      Keyword.RETHROW,
+      Keyword.RETURN,
+      Keyword.SWITCH,
+      Keyword.THROW,
+      Keyword.TRY,
+      Keyword.VAR,
+      Keyword.VOID,
+      Keyword.WHILE
+    ]);
+  }
+
   void _addSuggestion(Keyword keyword,
       [int relevance = DART_RELEVANCE_DEFAULT]) {
     String completion = keyword.syntax;
     request.addSuggestion(new CompletionSuggestion(
         CompletionSuggestionKind.KEYWORD, relevance, completion,
         completion.length, 0, false, false));
   }
 
   void _addSuggestions(List<Keyword> keywords,
       [int relevance = DART_RELEVANCE_KEYWORD]) {
     keywords.forEach((Keyword keyword) {
       _addSuggestion(keyword, relevance);
     });
   }
 
   bool _isInClassMemberBody(AstNode node) {
     while (true) {
       AstNode body = node.getAncestor((n) => n is FunctionBody);
       if (body == null) {
         return false;
       }
       AstNode parent = body.parent;
       if (parent is ConstructorDeclaration || parent is MethodDeclaration) {
         return true;
       }
       node = parent;
     }
   }
 }