File formats don't use parent configuration

I gave an example class: PropertiesConfigurationFileFormat

Ooh, I see the problem, you're talking about the internal implementation, by your example I thought that the user is the one that should be doing that.

parentConfiguration is nullable and can simply be passed along. The problem is that it is not being passed along.

I think you didn't express yourself correctly on this ticket.

Isn't "X should be Y" pretty clear?

I think you didn't express yourself correctly on this ticket.

We should yet have both of these options:

But the problem is that findParameterImpl(key) or load(configuration, parentConfiguration) is not actually looking at the parent configuration, if provided, and the property is not present on the actual configuration.

This is what this ticket is about, right?

We probably need to add a unit test to each file format where we pass it a parent configuration. (Whether you add it to the existing test or or create a new one is up to you.) It's easy to create a parent configuration; here's the Java 9+ version:

For this (currently) Java 8 code you can look up an easy way to create a map, but that's the idea.