CompilerBug.groovy

import java.util.function.Predicate
import groovy.transform.CompileStatic

@CompileStatic
class CompilerBug {

    void working() {
        List<String> list = []
        list + (String) null
        list + (String) null
        list + 'foo'
        list + (String) null
        list + 'bar'
        list + (String) null

        assert 6 == list.size()
        list.removeIf( {it == null} as Predicate )
        assert 2 == list.size()
    }

    void minimalWorking() {
        ([] as List<String>).removeIf({it == null} as Predicate)
    }

    void broken() {
        List<String> list = []
        list + (String) null
        list + (String) null
        list + 'foo'
        list + (String) null
        list + 'bar'
        list + (String) null

        assert 6 == list.size()
        list.removeIf( {it == null} as Predicate<?> )
        assert 2 == list.size()
    }

    void minimalBroken() {
        ([] as List<String>).removeIf({it == null} as Predicate<?>)
    }
}