Hi everyone  am  very new in writing this apex code.. i have following trigger but any how i was able to write two test classes based on condition but was not able to code into single test class.. could anyone please provide me the code how to combine those two test classes into one.

Merging MQL Trigger:

trigger MQL on Opportunity (before update) 
{    
for(Opportunity a : Trigger.new)
{        
Opportunity beforeUpdate = System.Trigger.oldMap.get(a.Id);         
if(beforeUpdate.StageName =='Lead'||beforeUpdate.StageName == 'Qualified Lead')
{   
If(a.StageName != 'Lead' && a.StageName != 'Qualified Lead' && a.StageName != 'No Opportunity')
{         
a.MQL_Promotion_Date__c = System.today();            
system.debug('*** Oppty changed from Lead to something other than Lead or No Opportunity - date set to ' + System.today()+' ****');
}
if(a.StageName == 'No Opportunity')
{
a.MQL_Rejection_Date__c = System.today();  
system.debug('*** Oppty changed from Lead to No Opportunity-date set to'+System.today() +'****');  
}                     
}   
} 
}

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@isTest
private class TestMQLPromotionDateTrigger
{
     static testMethod void myTest()
 {
    Datetime t = system.now();
    Date d = Date.newInstance(t.year(),t.month(),t.day());
 
opportunity opp1=new opportunity(Name='MQL',ForecastCategoryName='Pipeline',Region__c='EMEA', LeadSource='Progress Employee', CurrencyIsoCode='INR-Indian Rupee', StageName='Qualified Lead', Type='New Customer', Opportunity_Source__c='sales Rep - Direct', Industry__c='Education',  CloseDate = d);

// insert test opportunity
insert opp1;

// get opportunity and change stage

Opportunity updateOpportunity = [Select Name from Opportunity WHERE Name = 'MQL'];
updateOpportunity.StageName = 'D - Qualify';
update updateOpportunity;

// get updated MQL Promotion Date to verify that trigger populated the field with today's date

Opportunity getOpportunity = [Select MQL_Promotion_Date__c from Opportunity WHERE Name = 'MQL'];

Datetime t2 = system.now();         
Date d2 = Date.newInstance(t2.year(),t2.month(),t2.day());

System.assertEquals(getOpportunity.MQL_Promotion_Date__c,d2);
    }
}

------------------------------------------------------------------------------------------------------------------------------------------------------------------------
@isTest
private class TestMQLPromotionDateTrigger
{
     static testMethod void myTest()
 {

    Datetime t = system.now();
    Date d = Date.newInstance(t.year(),t.month(),t.day());

Opportunity opp1 = new opportunity(Name='MQL',ForecastCategoryName='Pipeline',Region__c='EMEA', LeadSource='Progress Employee', CurrencyIsoCode='INR-Indian Rupee', StageName='Qualified Lead', Type='New Customer', Opportunity_Source__c='sales Rep - Direct', Industry__c='Education',  CloseDate = d);

// insert test opportunity
insert opp1;

// get opportunity and change stage

Opportunity updateOpportunity = [Select Name from Opportunity WHERE Name = 'MQL'];
updateOpportunity.StageName = 'No Opportunity';
updateOpportunity.Stage_Reason__c = 'N - No Solution Fit';
update updateOpportunity;

// get updated MQL Rejection Date to verify that trigger populated the field with today's date

Opportunity getOpportunity = [Select MQL_Rejection_Date__c from Opportunity WHERE Name = 'MQL'];

Datetime t2 = system.now();         
Date d2 = Date.newInstance(t2.year(),t2.month(),t2.day());

System.assertEquals(getOpportunity.MQL_Rejection_Date__c,d2);    
    }
}

can anyone please provide me solution for these two test classes into one with the same condition please..!!