// the previous visit. It is important that this is NOT a heuristic
        // (it used to be) because if the filters are _equivalent_, we would
        // revisit all dependencies and possibly change the classpath order!
        boolean sameDependencies = dependencies(newResolutionFilter).equals(oldStates);
        if (sameDependencies) {

                    }
                }
            }
        """
        file("buildSrc/build.gradle") << """
            dependencies {
                classpath libs.lib
            }
        """

        when:
        fails ':help'

        then: "extension is not generated if there are no libraries defined"

The link:https://kotlinlang.org/docs/reference/compatibility.html[compatibility guarantees] provided by Kotlin apply for both backward and forward compatibility.

==== Backward compatibility

Method <org.gradle.plugins.ide.eclipse.model.EclipseModel.classpath(groovy.lang.Closure)> has arguments/return type groovy.lang.Closure that is not Gradle public API or primitive or built-in JDK classes or Kotlin classes in (EclipseModel.java:0)