Included builds in Gradle 4.10-rc3

I have a complex build where I’m currently manually invoking Gradle via exec() instead of using a GradleBuild task, because the second Gradle build also has an included build. (See my other posts if you feel the need to explore that)

Since Gradle v4.10 should have support for included builds within included builds, I wanted to try using a GradleBuild task with Gradle v4.10-rc3. However, when I try to do that, I get the following error:
Cannot include build 'foo' in build 'bar'. This is not supported yet.

It’s not clear to me what the restriction is. Can someone help enlighten me?

It appears to be related to this change:

I can see there are restrictions here:

But I’m not clear what restriction I’m violating. I’m not using buildSrc, as I needed flexibility with the directory location, so instead I’m using includedBuild from settings.gradle as a close substitute.

However, apparently I’m running afoul of some limitation – maybe an undocumented one?

Building composites with GradleBuild (still) isn’t supported. I think that’s what you are hitting based on your description.

@luke_daley Thank you for your reply. Sorry, I was away on vacation recently, so I didn’t get a follow up.

The release notes say that “composite builds can now be nested”. Are you saying that this works with something like includedBuild, but not when I use a GradleBuild task? Is there any chance this would work soon, since it seems like the core issue is now addressed? It would really help clean up my current build structure…