How to force a virtual platform

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1

Hi,

I noticed the changes made by @CedricChampeau in https://github.com/gradle/gradle/pull/6452 and wanted to follow-up with a question:
While it’s possible to force a component of a virtual platform, which will align the whole platform to that component’s version, how do I force this platform to a specific version, in a way that fails if there are transitives that require a higher version?

Given this code (on gradle-5.0-20180924235845+0000):

apply plugin: 'java-library'

dependencies {
    components.all { ComponentMetadataDetails details ->
        if (details.id.group.startsWith("com.fasterxml.jackson.")) {   
            details.belongsTo "com.fasterxml.jackson:platform:${details.id.version}"
        }
    }

    // Let's assume these are transitives
    compile 'com.fasterxml.jackson.core:jackson-databind:2.9.3'
    compile 'com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:2.9.0'
}

I know you can constrain one of the components of the platform and that will align the whole platform to that version:

dependencies {
    constraints {
        implementation "com.fasterxml.jackson.core:jackson-databind:2.9.5"
    }
}

But I’d like to express this constraint in terms of the platform, without knowing ahead of time what components might be in the platform.

Is there a way to do that?

I’ve tried to add the platform itself as a constraint (platform or otherwise) but that makes gradle try to resolve it, so I’m guessing it no longer considers it a virtual platform:

dependencies {
    constraints {
        implementation enforcedPlatform("com.fasterxml.jackson:platform:2.9.5")
    }
}

Thanks,
Dan