Nested composite builds are not "flattened"

[reline]

Current Behavior

A nested composite build is not in the list of included builds for the root project.

Expected Behavior

When a composite build is included in another composite build, both builds have the same parent. In other words, the nested composite build structure is flattened.

https://docs.gradle.org/8.7/userguide/composite_builds.html#included_builds

Context (optional)

No response

Steps to Reproduce

// settings.gradle.kts
includeBuild("core")
// build.gradle.kts
println("Root project included builds: ${gradle.includedBuilds.joinToString(",") { it.name }}")

// core/settings.gradle.kts
includeBuild("../thirdparty")
// core/build.gradle.kts
println("Core project included builds: ${gradle.includedBuilds.joinToString(",") { it.name }}")

$ ./gradlew --dry-run

> Configure project :core
Core project included builds: thirdparty

> Configure project :
Root project included builds: core
:help SKIPPED

BUILD SUCCESSFUL in 764ms

Minimum reproducible example here: https://github.com/reline/gradle-nested-composite-build

Gradle version

8.7

Build scan URL (optional)

No response

Your Environment (optional)

No response

[ov7a]

This issue needs a decision from the team responsible for that area. They have been informed. Response time may vary.

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This is indeed inconsistent, so the team will decide if we should change the output or just update the docs.

[mlopatkin]

This documentation issue is confirmed.

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We have several places where "flattening" can happen, so maybe the docs are talking about something else, like gradle.parent. We need to figure that out and clarify.