New NodeLocator which uses positions of characters, not between them.

pkg/analyzer/test/generated/ast_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 engine.ast_test;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/java_core.dart';
 import 'package:analyzer/src/generated/java_engine.dart' show Predicate;
 import 'package:analyzer/src/generated/java_engine.dart';
@@ skipping 11 matching lines @@
   initializeTestEnvironment();
   runReflectiveTests(BreadthFirstVisitorTest);
   runReflectiveTests(ClassDeclarationTest);
   runReflectiveTests(ClassTypeAliasTest);
   runReflectiveTests(ConstantEvaluatorTest);
   runReflectiveTests(ConstructorDeclarationTest);
   runReflectiveTests(FieldFormalParameterTest);
   runReflectiveTests(IndexExpressionTest);
   runReflectiveTests(NodeListTest);
   runReflectiveTests(NodeLocatorTest);
+  runReflectiveTests(NodeLocator2Test);
   runReflectiveTests(SimpleIdentifierTest);
   runReflectiveTests(SimpleStringLiteralTest);
   runReflectiveTests(StringInterpolationTest);
   runReflectiveTests(ToSourceVisitorTest);
   runReflectiveTests(VariableDeclarationTest);
 }
 
 class AssignmentKind extends Enum<AssignmentKind> {
   static const AssignmentKind BINARY = const AssignmentKind('BINARY', 0);
 
@@ skipping 896 matching lines @@
     try {
       javaListSet(list, 1, node);
       fail("Expected IndexOutOfBoundsException");
     } on RangeError {
       // Expected
     }
   }
 }
 
 @reflectiveTest
+class NodeLocator2Test extends ParserTestCase {
+  void test_onlyStartOffset() {
+    CompilationUnit unit = ParserTestCase.parseCompilationUnit(' int vv;');
+    TopLevelVariableDeclaration declaration = unit.declarations[0];
+    VariableDeclarationList variableList = declaration.variables;
+    Identifier typeName = variableList.type.name;
+    expect(new NodeLocator2(0).searchWithin(unit), same(unit));
+    expect(new NodeLocator2(1).searchWithin(unit), same(typeName));
+    expect(new NodeLocator2(2).searchWithin(unit), same(typeName));
+    expect(new NodeLocator2(3).searchWithin(unit), same(typeName));
+    expect(new NodeLocator2(4).searchWithin(unit), same(variableList));
+  }
+
+  void test_startEndOffset() {
+    CompilationUnit unit = ParserTestCase.parseCompilationUnit(' int vv; ');
+    TopLevelVariableDeclaration declaration = unit.declarations[0];
+    VariableDeclarationList variableList = declaration.variables;
+    Identifier typeName = variableList.type.name;
+    SimpleIdentifier varName = variableList.variables[0].name;
+    expect(new NodeLocator2(0, 2).searchWithin(unit), same(unit));
+    expect(new NodeLocator2(1, 2).searchWithin(unit), same(typeName));
+    expect(new NodeLocator2(1, 3).searchWithin(unit), same(typeName));
+    expect(new NodeLocator2(1, 4).searchWithin(unit), same(variableList));
+    expect(new NodeLocator2(5, 6).searchWithin(unit), same(varName));
+    expect(new NodeLocator2(5, 7).searchWithin(unit), same(declaration));
+  }
+}
+
+@reflectiveTest
 class NodeLocatorTest extends ParserTestCase {
   void test_range() {
     CompilationUnit unit =
         ParserTestCase.parseCompilationUnit("library myLib;");
     _assertLocate(
         unit, 4, 10, (node) => node is LibraryDirective, LibraryDirective);
   }
 
   void test_searchWithin_null() {
     NodeLocator locator = new NodeLocator(0, 0);
@@ skipping 2962 matching lines @@
   static const List<WrapperKind> values = const [
     PREFIXED_LEFT,
     PREFIXED_RIGHT,
     PROPERTY_LEFT,
     PROPERTY_RIGHT,
     NONE
   ];
 
   const WrapperKind(String name, int ordinal) : super(name, ordinal);
 }