How to write a test method/class

Question

I have created a simple apex class to be used in conjunction with a visualforce page. Everything is working as I had intended it to in the sandbox and I am now ready to push it over to production. The only problem is that I have no idea how or where to begin writing a test class to test my code coverage.

Here is the class that I created:

public with sharing class clsOpportunity10 {

    public PageReference save() {
        update opportunities;       
        update prospects;
        update pursuits;
        update closing;
        update budgeting;
        update promised;
        return null;
    }


    public List<Opportunity> opportunities {get;set;}
    public clsOpportunity10()
    {
        opportunities = [select name, Project_Delivery_Method__c, Amount, Gross_Margin__c, Gross_Margin1__c, Probability, Probability_of_Owner_Proceeding__c, Bid_Due_Date__c, CloseDate, stagename, First_Year_Burn__c, Second_Year_Burn__c, Third_Year_Burn__c, Fourth_Year_Burn__c, Current_120_Day_List__c, Affecting_Current_Year_Book_and_Burn__c, Pathway_to_CY_Plan__c from opportunity where StageName = 'Needs Qualifying' and Branch__c = '10 - Western PA' and RecordType.Name = 'Construction' ORDER BY Probability DESC];
    }

    public list<Opportunity> prospects {get;set;}

    {
        prospects = [select name, Project_Delivery_Method__c, Amount, Gross_Margin__c, Gross_Margin1__c, Probability, Probability_of_Owner_Proceeding__c, Bid_Due_Date__c, CloseDate, stagename, First_Year_Burn__c, Second_Year_Burn__c, Third_Year_Burn__c, Fourth_Year_Burn__c, Current_120_Day_List__c, Affecting_Current_Year_Book_and_Burn__c, Pathway_to_CY_Plan__c from opportunity where StageName = 'Selling' and Branch__c = '10 - Western PA' and RecordType.Name = 'Construction' ORDER BY Probability DESC];
    }

    public list<Opportunity> pursuits {get;set;}

    {
        pursuits = [select name, Project_Delivery_Method__c, Amount, Gross_Margin__c, Gross_Margin1__c, Probability, Probability_of_Owner_Proceeding__c, Bid_Due_Date__c, CloseDate, stagename, First_Year_Burn__c, Second_Year_Burn__c, Third_Year_Burn__c, Fourth_Year_Burn__c, Current_120_Day_List__c, Affecting_Current_Year_Book_and_Burn__c, Pathway_to_CY_Plan__c from opportunity where StageName = 'Proposal' and Branch__c = '10 - Western PA' and RecordType.Name = 'Construction' ORDER BY Probability DESC];
    }

     public list<Opportunity> closing {get;set;}

    {
        closing = [select name, Project_Delivery_Method__c, Amount, Gross_Margin__c, Gross_Margin1__c, Probability, Probability_of_Owner_Proceeding__c, Bid_Due_Date__c, CloseDate, stagename, First_Year_Burn__c, Second_Year_Burn__c, Third_Year_Burn__c, Fourth_Year_Burn__c, Current_120_Day_List__c, Affecting_Current_Year_Book_and_Burn__c, Pathway_to_CY_Plan__c from opportunity where StageName = 'Closing' and Branch__c = '10 - Western PA' and RecordType.Name = 'Construction' ORDER BY Probability DESC];
    }

     public list<Opportunity> budgeting {get;set;}

    {
        budgeting = [select name, Project_Delivery_Method__c, Amount, Gross_Margin__c, Gross_Margin1__c, Probability, Probability_of_Owner_Proceeding__c, Bid_Due_Date__c, CloseDate, stagename, First_Year_Burn__c, Second_Year_Burn__c, Third_Year_Burn__c, Fourth_Year_Burn__c, Current_120_Day_List__c, Affecting_Current_Year_Book_and_Burn__c, Pathway_to_CY_Plan__c from opportunity where StageName = 'Budgeting' and Branch__c = '10 - Western PA' and RecordType.Name = 'Construction' ORDER BY Probability DESC];
    }

     public list<Opportunity> promised {get;set;}

    {
        promised = [select name, Project_Delivery_Method__c, Amount, Gross_Margin__c, Gross_Margin1__c, Probability, Probability_of_Owner_Proceeding__c, Bid_Due_Date__c, CloseDate, stagename, First_Year_Burn__c, Second_Year_Burn__c, Third_Year_Burn__c, Fourth_Year_Burn__c, Current_120_Day_List__c, Affecting_Current_Year_Book_and_Burn__c, Pathway_to_CY_Plan__c from opportunity where StageName = 'Promised' and Branch__c = '10 - Western PA' and RecordType.Name = 'Construction' ORDER BY Probability DESC];
    }

}

I am new to apex (and writing code in general) so, any help would be greatly appreciated.

Answer 1

You can refer this link An Introduction to Apex Code Test Methods

to start writing test classes.

Below I have tried to show you following things: 1. How to create setup data. 2. How to create user for which you will run the test scenarios.

@isTest
public class clsOpportunity10_Test{
@testSetup static void prepareControllerClassData() 
{
    //retrieve the profile information
    Map<String,Id> profileIdNameMap = TestUtil.prepareProfileIdNameMap();

   //create Executive user.
    User mbExecutiveUser = TestUtil.createUser('Executive', 'user', profileIdNameMap.get('Executive')); 
    System.runAs(mbExecutiveUser)
     {
         createOpportunities();            
     }      
}


// create an user for the test class 
public static User createUser(String firstName, String lastName, String profileId){
    String sRandom = String.ValueOf(Integer.valueOf(math.rint(math.random()*1000000)));
    User newUser = new User(
                ProfileId = profileId,
                Firstname=firstName,
                Lastname=lastName,
                Username = firstName + sRandom + '@xyz.com',                    
                Alias = firstName.substring(0,2) + lastName.substring(0,2),
                Email=firstName + lastName + '@xyz.com',
                EmailEncodingKey='UTF-8',
                LanguageLocaleKey='en_US',                    
                LocaleSidKey='en_US',
                TimeZoneSidKey='America/Chicago'
            );
    return newUser;
}

public static Map<String,Id> prepareProfileIdNameMap()
{
    if(profileIdNameMap.isEmpty())
    {
        List<Profile> lstProfile = [SELECT Id, Name FROM Profile WHERE Name IN (<specify all the profile names>)];

        for(Profile objProfile:lstProfile)
        {
            profileIdNameMap.put(objProfile.Name, objProfile.Id);
        }            
    }
    return profileIdNameMap;        
}

public static void createOpportunities()
{
    List<Opportunity> lstOpportunity = new List<Opportunity>();
    Opportunity oppty1 = new Opportunity();
    oppty1.RecordTypeId= Schema.SObjectType.Opportunity.getRecordTypeInfosByName().get('Construction').getRecordTypeId();
    oppty1.StageName = 'Needs Qualifying';
    oppty1.Branch__c = '10 - Western PA';
    //assign all the values to be respective attributes
    lstOpportunity.add(oppty1);

    //same way for other stages and branches create opportunity data.
    //and finally insert the list
    insert(lstOpportunity);
}

public static void updateOpportunities()
{
    System.runAs(mbExecutiveUser)
    {
        //you will retrieve the opportunity record

        //update the record

        //put System.assert() to verify values
    }
}}