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// Test Class

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@isTest

public class SSFInvokeMethodTester {

    @isTest static void TestInvokeThisMethod(){   

    Test.startTest(); 

    String accountNameNew = 'How Now Brown Cow Enterprises' ;    

    //Create Account

    String AccountNameOrig ='Acme' ;    

    Account testAcct = new Account() ;

    testAcct.Name = AccountNameOrig ;

    testAcct.Phone = '(415)555-1212';

    testAcct.NumberOfEmployees = 100;

    Insert testAcct ;

    Account acctQuery = [select Id, Name from Account where Id = :testAcct.id  ]   ;

     // Load Input Parameters   

     SSFInvokeMethod.methodInputs params = new SSFInvokeMethod.methodInputs() ;

      params.accountSobj = acctQuery ;    

     params.newAccountName=accountNameNew; 

     List<SSFInvokeMethod.methodInputs> paramList = new List<SSFInvokeMethod.methodInputs>() ;

      paramList.add(params) ;

     List<SSFInvokeMethod.methodOutputs> returnedResults =  SSFInvokeMethod.invokeThisMethod(paramList) ;

     System.debug('result DMLResult:  ' +  returnedResults[0].DMLResult   ) ;

      System.debug('result accountPreviousName:  ' +  returnedResults[0].accountPreviousName   ) ;

     System.assertEquals( returnedResults[0].DMLResult , 'Success' , 'DMLResult failed assertion');   

     System.assertEquals( returnedResults[0].accountPreviousName , AccountNameOrig , 'accountPreviousName  failed assertion');       

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       Test.stopTest();

    }

}