What is the use of System.assertEquals() in Salesforce?

Hi Avnish,

We use System.assertEquals in our test methods basically to check whether the two values are equal or not.One of the value is said to be expected value which we expect while making dummy variables and giving values to it. The second is the actual result which we get on passing the variable in the given class method. System.assertEquals() returns true if the values are equal and throws an exception message(which is also provided by us) in case they are unequal.

Hi,

System.AssertEquals and System.AssertNotEquals both accepts three parameters; the first two (mandatory) are the variables that will be tested for in/equality and the third (optional) is the message to display if the assert results in false.

example -

static testMethod void runNegativeTestCases(){
User u3 = [select id from User where alias='tuser'];
System.RunAs(u3)
{
System.debug('Inserting a record with 501 miles... (negative test case)');

Mileage__c testMiles3 = new Mileage__c( Miles__c = 501, Date__c = System.today() );
try{

insert testMiles3;

}catch (DmlException e){

//Assert Error Message

System.assert( e.getMessage().contains('Insert failed. First exception on ' +'row 0; first error:FIELD_CUSTOM_VALIDATION_EXCEPTION,'+'Mileage request exceeds daily limit(500): [Miles__c]'),e.getMessage() );

//Assert field

System.assertEquals(Mileage__c.Miles__c, e.getDmlFields(0)[0]);

//Assert Status Code

System.assertEquals('FIELD_CUSTOM_VALIDATION_EXCEPTION' , e.getDmlStatusCode(0) );

} //catch

} //RunAs(u3)

Hope this helps.