Need of Test Class

Question

I have written a simple trigger which does some validation. I am trying to understand, if it's really necessary to write Test Class for this. The code coverage is 0%, hence please someone help to understand how to write Test Class for the below code.

trigger Duplicate_Prospect_Check on Account (before insert)

{    
list <Account> Acc = [Select id from Account where Account.name=:trigger.new[0].name and Account.Siebel_Account_ID__c=:trigger.new[0].Siebel_Account_ID__c];

    if(Acc.size()>0)
    {
        trigger.new[0].name.addError('Prospect Account with same Name and Account Id already exists');
     }
}

So I added below code in my Test Class and it ran successfully. But my actual trigger is still not giving 100% code coverage. It's not covering 'addError' statement.

private class Duplicate_Prospect_Check_TriggerTest

 {

static testmethod void test()

    {
        List<Account> acts = new List<Account>();
        for(Integer i=0; i<2; i++)
        {
            Account a = new Account(Name='Duptest',ShippingCity='Boston',ShippingCountry='United States',ShippingState='MA'); 
            acts.add(a);
        }  
        try
        {      
           test.startTest();
           insert acts;
           test.stopTest();
         }  
         catch(Exception e)
        {
            System.Assert(e.getMessage().contains('FIELD_CUSTOM_VALIDATION_EXCEPTION'));
        }
    }
}

Answer 1

To test a trigger all you need is for your test method to perform the operations for which the trigger is declared. In this case you declared a trigger for insertions. So an insertion of an Account will do. More or less like:

@isTest
static testMethod testInsert() {
  Account account = new Account();
  // set account fields according to your needs
  insert account;
  // your assertions
}

Answer 2

Hi @Amulya i shared a sample test class for you.As per i understood about your problem there are two types of users.So,create a user with your required profile and try to create account with user.And always try to bulk testing it is also one of the best practice.

@isTest
public class TestFssTeamUpdateoppo
{
static testMethod void testStandardUseropp() 
{
    // Create a new user with the Standard User profile
    Profile standardProf = [select id from profile where name='Standard User']; 
    User su = new User(alias = 'standt', email='standarduser@testorg.com',emailencodingkey='UTF-8',FirstName='opp',
                       lastname='testing',languagelocalekey='en_US',localesidkey='en_US',profileid = standardProf.Id,
                       timezonesidkey='America/Los_Angeles',username='sample@opptest.com');
    // Switch current user to Standard User
    System.runAs(su)
    {

        List<account> Accounts = new List<account> {};
        for(Integer i = 0; i < 200; i++)
        {
                Account a = new Account();
                Accounts.add(a);
        }
        test.startTest();
        // Insert the Account records that cause the trigger to execute.
        insert Accounts;
      // Stop the test, this changes limit context back to test fromtrigger.
        test.stopTest();

    }
}
}