Groovy, how to mock interface keeping other methods - unit-testing

Question

How to mock an object that implements an interface and methods not belonging to the latter? I need aplicacaoPT to implement BindingProvider and buscaAplicacaoPorCodigo. The cast works but the buscaAplicacaoPorCodigo call gives a MissingMethodException. I tried with a map and an Expando:
import static org.junit.Assert.*
import grails.test.mixin.*
import grails.test.mixin.support.*
import org.junit.*
import javax.xml.ws.BindingProvider
#TestMixin(GrailsUnitTestMixin)
class CatalogClientServiceTests {
void testFetch() {
AplicacaoSoapService.metaClass.getAplicacaoSoapPort = {
[ getRequestContext: { new HashMap<String, Object>() },
buscaAplicacaoPorCodigo: { String appCode -> "carrapato!" } ] as BindingProvider
}
def applicationDataFromCatalog = service.fetch("dino")
}
void testFetchFailsWithInvalidApplicationCode() {
AplicacaoSoapService.metaClass.getAplicacaoSoapPort = {
def aplicacaoSoapPort = new Expando()
aplicacaoSoapPort.getRequestContext = { new HashMap<String, Object>() }
aplicacaoSoapPort.buscaAplicacaoPorCodigo = { String appCode -> "castanha!" }
aplicacaoSoapPort as BindingProvider
}
shouldFail(IllegalArgumentException) { service.fetch("dino") }
}
}
import javax.xml.ws.BindingProvider
class CatalogClientService {
def aplicacaoPT = new AplicacaoSoapService().getAplicacaoSoapPort()
def grailsApplication
def fetch(String appCode) {
Map<String, Object> req_ctx = ((BindingProvider)aplicacaoPT).getRequestContext();
req_ctx.put(BindingProvider.ENDPOINT_ADDRESS_PROPERTY, grailsApplication.config.catalogAppEndPointAddress);
def response = aplicacaoPT.buscaAplicacaoPorCodigo(appCode)
println "response: $response"
}
}
I also tried adding buscaAplicacaoPorCodigo to BindingProvider's metaclass but it sticks with one of the implementations for all tests. In the example below response will be printed (above) either "castanha!" or "carrapato!" on both tests for each run.
import static org.junit.Assert.*
import grails.test.mixin.*
import grails.test.mixin.support.*
import org.junit.*
import javax.xml.ws.BindingProvider
#TestMixin(GrailsUnitTestMixin)
class CatalogClientServiceTests {
void testFetch() {
BindingProvider.metaClass.buscaAplicacaoPorCodigo = { String appCode -> "carrapato!" }
AplicacaoSoapService.metaClass.getAplicacaoSoapPort = {
[ getRequestContext: { new HashMap<String, Object>() } ] as BindingProvider
}
def applicationDataFromCatalog = service.fetch("dino")
}
void testFetchFailsWithInvalidApplicationCode() {
BindingProvider.metaClass.buscaAplicacaoPorCodigo = { String appCode -> "castanha!" }
AplicacaoSoapService.metaClass.getAplicacaoSoapPort = {
def aplicacaoSoapPort = new Expando()
aplicacaoSoapPort.getRequestContext = { new HashMap<String, Object>() }
aplicacaoSoapPort as BindingProvider
}
shouldFail(IllegalArgumentException) { service.fetch("dino") }
}
}
I stripped parts of the code above for the sake of simplicity.
I hope some of may help me! :)

Answer 1

I have zero experience with grails, but this seems a problem related with proxies. The resulting proxy doesn't have the buscaAplicacaoPorCodigo available.
AFAIK, you have two choices: either create a interface Buscador, with buscaAplicacaoPorCodigo, and create a super interface for both BindingProvider and Buscador, or, for a pure dynamic solution, metaClass the resulting proxied expando:
I mocked some of your classes, hope I got it right.
BindingProvider.groovy:
interface BindingProvider {
def getRequestContext()
}
And the rest:
class AplicacaoSoapService {
static BindingProvider getAplicacaoSoapPort() {
assert false, "Nope, must be mocked"
}
}
AplicacaoSoapService.metaClass.static.getAplicacaoSoapPort = {
def e = new Expando(
getRequestContext: { [:] }) as BindingProvider
e.getMetaClass().buscaAplicacaoPorCodigo = { String a -> "amendoa!" }
e
}
def provider = AplicacaoSoapService.aplicacaoSoapPort
assert provider.buscaAplicacaoPorCodigo("pudim") == "amendoa!"