@isTest
public class FeedCommentTriggerTest {
    
    @isTest
    public static void testFeedCommentTrigger() {
        
        //Create a User with Profile 'Net Planning Department'
        Id pid = [Select Id FROM Profile WHERE Name = 'Net Planning Department'].Id;
        
        User u = new User();
        u.ProfileId = pid;
        //here fill all the required fields for the User Record
        insert u;
        
        SALES_ENGINEERING_REQUEST__c s = new SALES_ENGINEERING_REQUEST__c();
        s.Status__c = //any Value othe than "Approved" and "Unable to Meet Request"
        //here fill all the required fields for the SALES_ENGINEERING_REQUEST__c Record
        insert s;
        
        //Since test class runs in the current user mode and in this Trigger lines will be covered only when the    //User has a Profile - 'Net Planning Department' hence we need trigger this event as the new User created with this //Profile
        System.runAs(u) {
            FeedComment f = new FeedComment();
            f.ParentId = s.Id;
            //here fill all the required fields for FeedCommentRecord
            
            Test.startTest();
            insert f;
            Test.stopTest();
        }
        
        
        SALES_ENGINEERING_REQUEST__c updatedRecord = [SELECT Id,Status__c  FROM SALES_ENGINEERING_REQUEST__c WHERE Id =: s.Id];
        System.assertequals('Approved',updatedRecord.Status__c);
    }
    
}