would it be reasonable to contribute an extension function i wrote

inline fun <reified T : Any> PropertyResolver.getProperty(key: String, default: T): T {
    return getProperty(key, T::class.java, default)
}

upstream to spring? (can anyone on the spring team here give me some guidance on that?)

I'm not in the spring team, but the variants without default are already there, so it should be no issue to add the defaulted one as well. I guess you'll need to make it an expression function, and add documentation and a test.

Oh nice. I'll follow the lead of those. Thanks for the hint.