BOM dependencies not resolved in custom configuration

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1

Hi there, I’ve got a multi-project build, and in the root project I define a few configurations to aid with packaging. Using a BOM for constraints in all subprojects.

subprojects {
  dependencies {
    implementation platform(group: 'org.eclipse.jetty', name: 'jetty-bom', version: 9.4.27.v20200227)
  }
}

configuration {
  someLib
}

dependencies {
  someLib project(":some-subproject")
}

In the subproject:

dependencies {
  implementation group: 'com.example', name: 'my-artifact'
  implementation group: 'org.eclipse.jetty', name: 'jetty-server'
  implementation group: 'org.eclipse.jetty', name: 'jetty-servlets'
}

The artifact my-artifact has a transitive dependency on ‘jetty-server’ but not on ‘jetty-servlets’.
The subproject compiles and dependencies resolve correctly with the expected constraints introduced by the BOM.

However, in the root project, the configuration ‘someLib’ which depends on the subproject, the jetty-servlets dependency does not resolve, only dependencies that also are transitively required by the subproject, and they resolve to the version in the transitive dependency and ignore the BOM.

 +--- org.eclipse.jetty:jetty-server -> 9.4.22.v20191022 (*)
 +--- org.eclipse.jetty:jetty-servlet -> 9.4.22.v20191022 (*)
 +--- org.eclipse.jetty:jetty-servlets FAILED
 +--- org.eclipse.jetty:jetty-util -> 9.4.22.v20191022

From the debug log, it appears that the version from the BOM is not considered in trying to resolve the artifact:

2020-03-03T11:21:27.121-0800 [DEBUG] [org.gradle.api.internal.artifacts.ivyservice.ivyresolve.CachingModuleComponentRepository] Detected non-existence of module 'org.eclipse.jetty:jetty-servlets:' in resolver cache 'BintrayJCenter'

Any idea why resolution is not honoring the BOM in this case?

My current workaround is to create a distribution directory in the subproject that resolves correctly and consume those files instead of using the custom configuration in the root project.

e.g. from project(':my-subproject').tasks.dist