Document extension search

[matthiaskraaz]

Expected Behavior

Documentation should in detail explain how extension properties are search.

Current Behavior

The only hint I found was "Extra properties on a project are visible from its subprojects."
at https://docs.gradle.org/current/userguide/writing_build_scripts.html#sec:extra_properties

Context

I had to do a lot of experimenting. I think I finally got it:

If you write just the name of the extension property:

1. outside of a task, the current project's extension is searched, then the parent projects up to the root project.
2. inside of a task, the task's extension is searched first, then as in 1

If you prepend ext like this: 'ext.myprop', the ext object is used instead for your context, i.e. the task ext if within a task. The project.ext if not within a task. So only that ext object is asked for that property and the above search strategy does not take place.

I don't know about the other extension aware objects (SourceSet, DependencyHandler, Settings).