add mockito 2.18.3 as test dependency
@@ -54,6 +54,7 @@ dependencies {
testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-api', version: junitJupiterVersion
testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-params', version: junitJupiterVersion
testCompile group: 'nl.jqno.equalsverifier', name: 'equalsverifier', version: '2.4.1'
+ testCompile group: 'org.mockito', name: 'mockito-core', version: '2.18.3'
testRuntime group: 'org.junit.vintage', name: 'junit-vintage-engine', version: junitVintageVersion
testRuntime group: 'org.junit.jupiter', name: 'junit-jupiter-engine', version: junitJupiterVersion
