How to mock passwordEncoder using Spock in a Grails unit test - unit-testing

Question

I could use some advice in how to mock an auto wired dependency used in a Grails unit test. I've omitted most of the unnecessary code and just given the test class and the relevant methods in the file class under test
class UserService {
def springSecurityService // spring bean
def passwordEncoder // auto wired as per
//https://stackoverflow.com/questions/33303585/spring-//security-encode-password-with- bcrypt-algorithm
.....
def passwordPreviouslyUsed(String newPassword, def userId){
def passwordExists = false
def usersPasswords = findPasswordsForUser(userId)
usersPasswords.each{ password ->
if (passwordEncoder.isPasswordValid(oldPassword, newPassword, null)) {
passwordExists = true
}
}
return passwordExists
}
.....
def findPasswordsForUser(def userId){
User foundUser = User.findById(userId)
def passwordsForUser = UserPasswords.createCriteria().list {
eq('user', foundUser)
projections{
property('password')
}
}
passwordsForUser
}
My test
class UserServiceSpec extends Specification implements DataTest, ServiceUnitTest<UserService> {
def passwordEncoder
def setupSpec() {
mockDomains User, UserPasswords
}
def setup() {
def stubPasswordEncoder = Stub(passwordEncoder) {
isPasswordValid(_, _, _) >> true
}
service.passwordEncoder = stubPasswordEncoder
}
void "test for user passwordPreviouslyUsed"() {
given: "a user already exists"
setup()
service.createNewUser("testName", "testy#test.com", "Secret1234" )
//^(does some validation, then User.save())
User foundUser = User.findByEmail("testy#test.com")
foundUser.fullName == "testName"
long testUserId = foundUser.id
and: "we update the password for that user, and it to the userPasswords"
UserPasswords newUserPassword = new UserPasswords(
user: foundUser,
password: "newPassword1"
)
newUserPassword.save()
//use passwordPreviouslyUsed method to check a string with the same value as the
//previously
//updated password to check if it has already been used
when: "we check if the password has been used before"
def response = service.passwordPreviouslyUsed("newPassword1", fundsyId)
then:
response == true
}
Without stubbing or mocking this dependency, I get the error
Cannot invoke method isPasswordValid() on null object
I tried to stub password encoder and have it return true
def stubPasswordEncoder = Stub(passwordEncoder) {
isPasswordValid(_, _, _) >> true
}
service.passwordEncoder = stubPasswordEncoder
But this gives an error message:
Stub in 'spock.mock.MockingApi' cannot be applied to '(java.lang.Object, groovy.lang.Closure)'
Is there any way to mock this dependency with Spock?

Answer 1

Stub and Mock take a class - you're giving it an instance that is null - hence the exception.
You should be able to mock it as so:
def mockPasswordEncoder = Mock(PasswordEncoder)
// note this is the class
// org.springframework.security.crypto.password.PasswordEncoder

Answer 2

I tried enrichelgeson's approach, and it worked!
I first imported PasswordEncoder to the test class
import org.springframework.security.crypto.password.PasswordEncoder
then implemented the normal mocking procedure. I was initially confused because they class under test just implicitly created an instance of the class by defining it.
def stubPasswordEncoder = Stub(PasswordEncoder) {
isPasswordValid(_, _, _) >> true
}
service.passwordEncoder = stubPasswordEncoder
I also found another solution that didn't require mocking
service.passwordEncoder = [ isPasswordValid: { String rawPass, String salt, Null -> true } ]
Both approaches work fine. Thanks for the help!