Testing ExtendedProperties

I’ve set up some extended properties in my plugin, and I want to unit test they are set.

In my simple mind this should work:

def "project object has antBuilderInput ext property"() {
        setup:
        def ext = project.ext.antBuilderInput

        expect:
        ext != null
    }

Interestingly the test fails during the setup phase, because its not there.

cannot get property ‘antBuilderInput’ on extra properties extension as it does not exist
groovy.lang.MissingPropertyException: cannot get property ‘antBuilderInput’ on extra properties extension as it does not exist
at org.gradle.api.internal.plugins.DefaultExtraPropertiesExtension.getProperty(DefaultExtraPropertiesExtension.java:56)
at com.lv.plugins.weblogic.WeblogicPluginSpec.project object has antBuilderInput property(WeblogicPluginSpec.groovy:120)

That’s kinda cool that Gradle handles this for me, but I need to assert this before runtime. My question therefore; what’s the best way to test for my antBuilderInput property?

I guess I’m doing the same as, here.