Configuration inheritance and resolution - gradle

Question

I have some trouble with gradle and I don't know why this doesn't work:
Project A with 2 sub-project B and C
B and C have a configuration named masterConfiguration and superConfiguration (who extend masterConfiguration)
I add some dependencies in both.
When I do this:
configurations.superConfigurations.resolvedConfiguration.files
All is fine, and I have all files from superConfiguration and masterConfiguration.
Now, the problem.
I create a configuration (projectAConfiguration) in the project A (the rootProject).
This configuration extends superConfiguration from B and C.
I add no new dependencies in this one.
If I do this:
configurations.projectAConfiguration.resolvedConfiguration.files
I have nothing. I don't understand why?
settings.gradle =>
include 'B'
include 'C'
build.gradle =>
configurations {
projectAConfiguration
}
def rootConfiguration = configurations.projectAConfiguration
subprojects {
configurations {
masterConfiguration
superConfiguration {
extendsFrom masterConfiguration
}
}
rootConfiguration.extendsFrom configurations.superConfiguration
dependencies {
masterConfiguration 'group:artifactid:version'
superConfiguration 'anotherGroup:anotherArtifactid:version'
}
//ALL IS OK
println configurations.superConfiguration.resolvedConfiguration.files
}
//NOT OK
println configurations.projectAConfiguration.resolvedConfiguration.files

Answer 1

I have solve my problem with this solution :
Add task on all subproject.
task resolveMyConf {
doLast {
it.ext.confResolve = it.configurations.superConfiguration..resolvedConfiguration.files
}
}
and in the project A
task resolveAllConf {
suprojects.each {
dependsOn it.resolveMyConf
}
doLast {
//and now, we can collect all task result
}
}
I don't know if it's good, maybe there is a better solution. But it works.

Answer 2

You can get the configuration of a sub-project just by referencing the project in the same way as you would declare a dependency to it. You don't need to create another configuration that extends it.
For example (Groovy DSL):
// Root project A
task printConfigurationB {
doLast {
println project("B").configurations.superConfiguration.resolve()
}
}