Grails生成的控制器测试在删除时失败

Question

我的Grails 3.1.8应用程序的所有生成的控制器测试仅在尝试删除域实例时失败。

错误是：

java.lang.NullPointerException: Cannot invoke method fire() on null object
    at gov.usda.fs.forecast.traits.UpdateMetadataTrait$Trait$Helper.afterDelete(UpdateMetadataTrait.groovy:30)
    at org.springframework.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:216)
    at org.springframework.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:201)
    at org.grails.datastore.gorm.events.DomainEventListener.invokeEvent(DomainEventListener.java:259)
    at org.grails.datastore.gorm.events.DomainEventListener.afterDelete(DomainEventListener.java:176)
    at org.grails.datastore.gorm.events.DomainEventListener.onPersistenceEvent(DomainEventListener.java:96)
    at org.grails.datastore.mapping.engine.event.AbstractPersistenceEventListener.onApplicationEvent(AbstractPersistenceEventListener.java:47)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:166)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:138)
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:381)
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:335)
    at org.grails.datastore.mapping.engine.EntityPersister.firePostDeleteEvent(EntityPersister.java:340)
    at org.grails.datastore.mapping.engine.NativeEntryEntityPersister.deleteEntity(NativeEntryEntityPersister.java:131)
    at org.grails.datastore.mapping.engine.EntityPersister.delete(EntityPersister.java:262)
    at org.grails.datastore.mapping.core.AbstractSession.delete(AbstractSession.java:728)
    at org.grails.datastore.gorm.GormInstanceApi.delete_closure9(GormInstanceApi.groovy:268)
    at groovy.lang.Closure.call(Closure.java:426)
    at org.grails.datastore.mapping.core.DatastoreUtils.execute(DatastoreUtils.java:310)
    at org.grails.datastore.gorm.AbstractDatastoreApi.execute(AbstractDatastoreApi.groovy:37)
    at org.grails.datastore.gorm.GormInstanceApi.delete(GormInstanceApi.groovy:267)
    at org.grails.datastore.gorm.GormEntity$Trait$Helper.delete(GormEntity.groovy:194)
    at gov.usda.fs.forecast.InvoiceStatusController.$tt__delete(InvoiceStatusController.groovy:91)
    at gov.usda.fs.forecast.InvoiceStatusController.delete_closure4(InvoiceStatusController.groovy)
    at groovy.lang.Closure.call(Closure.java:426)
    at groovy.lang.Closure.call(Closure.java:442)
    at grails.transaction.GrailsTransactionTemplate$2.doInTransaction(GrailsTransactionTemplate.groovy:96)
    at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133)
    at grails.transaction.GrailsTransactionTemplate.execute(GrailsTran

这是测试代码：

void "Test that the delete action deletes an instance if it exists"() {
    when:"The delete action is called for a null instance"
        request.contentType = FORM_CONTENT_TYPE
        request.method = 'DELETE'
        controller.delete(null)

    then:"A 404 is returned"
        response.redirectedUrl == '/invoiceStatus/index'
        flash.message != null

    when:"A domain instance is created"
        response.reset()
        populateValidParams(params)
        def invoiceStatus = new InvoiceStatus(params).save(flush: true)

    then:"It exists"
        InvoiceStatus.count() == 1

    // The test fails when issuing the delete
    when:"The domain instance is passed to the delete action"
        controller.delete(invoiceStatus)

    then:"The instance is deleted"
        InvoiceStatus.count() == 0
        response.redirectedUrl == '/invoiceStatus/index'
        flash.message != null
}

我在同一地点的每个生成的测试中得到相同的错误。任何线索都将非常感激。