text: const ts = require('typescript');
  var chai = require('chai');
  var expect = chai.expect;
  
  
  describe('fetures:test', function() {
  
  
      it('toCode test', function(){
          const node = ts.createSourceFile(
              'x.ts',`
                import { Component } from '@angular/core';
                @Component({selector: 'my', template: 'hello me.' })
                export class MyComponent {}`,
              ts.ScriptTarget.Latest
            );
  
            expect(node).to.be.not.null;
  
      });
  
      it('change code', function(){
          const node = ts.createSourceFile(
              'x.ts',`
                import { Component } from '@angular/core';
                @Component({selector: 'my', template: 'hello me.' })
                export class MyComponent {}`,
              ts.ScriptTarget.Latest
            );
          var classDecl;
          node.forEachChild(child => {
              if (ts.SyntaxKind[child.kind] === 'ClassDeclaration') {
              classDecl = child;
              }
          });
          classDecl.name.escapedText = 'ClassNameChanged';
          const printer = ts.createPrinter();
          const newContent = printer.printFile(node);
  
          let expected = 'import { Component } from "@angular/core";\n' +
                          '@Component({ selector: "my", template: "hello me." })\n' +
                          'export class ClassNameChanged {\n' +
                          '}\n';
          expect(newContent).to.be.eql(expected);
      });
  
  });