Sample Triggers and test classes

trigger createopp on Account (after insert) {

    list<opportunity> opp = new list<opportunity>();

    for(account a : trigger.new){

        if(a.industry == 'Education'){

            opportunity op = new opportunity();

            op.name = a.Name;

            op.AccountId = a.Id;

            op.Amount = 500;

            op.CloseDate = system.today()+30;

            op.StageName = 'prospecting';

            opp.add(op);

        }

       

    }

    insert opp;

}

Testclass:

@istest

public class createopp {

    public static testmethod void insertopp(){

        account a = new account(name = 'parugu',industry = 'education');

        opportunity o = new opportunity(name ='parugu',accountid = a.id,amount = 500,

                                        closedate = system.today()+30,StageName = 'prospecting');

       

        insert a;

        insert o;

       

    }

}

trigger samenoonaccount on Contact (before insert) {

   list<account> acc = new list<account>();

  

   for(contact c:trigger.new){

   acc = [select id,name,phone from account where phone =:c.accountid];

   if(acc.size()>0){

  

      c.adderror('phone no aleredy exists in account');

     

   }

  

   }

}

Testclass

@isTest

public class samnoaccount {

    public static testmethod void testphone(){

        string mphone = '9090909090';

        string adderror ;

        account a = new account(name = 'vedam',phone = mphone);

        contact c = new contact(lastname = 'anushka',accountid = a.id,phone = '9090909090');

        insert a;

        list<account> acc = [select id,phone from account where phone =: c.phone];

        if(acc.size()>0)

        try{

            insert c;

        }

        catch(Exception e){

           

            System.AssertEquals('phone no aleredy exists in account', adderror);

        }

     

       

       

    }

}

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