Multiple Build-Tasks with changing sets of dependencies in Gradle - gradle

Question

I would like to run tests of an library against different backend implementations.
The implementations are injected in my project by the magic of Spring.
Currently I do this, by changing the line
testImplementation group: 'org.mycorp.exmpl' name: 'redis-backend' version: '0.0.1'
to
testImplementation group: 'org.mycorp.exmpl' name: 'mongo-backend' version: '0.0.1'
to
testImplementation group: 'org.mycorp.exmpl' name: '<whatever-backend>' version: '<whatever.version>'
then running
gradlew test
(resp. clicking on 'test' in my IntelliJ IDE)
This is cumbersome. And I can't do that with my build pipeline (I guess).
In my imagination, I would be able to create
a task testRedis which depends on the task buildRedisTestClasses
a task testMongo which depends on the task buildMongoTestClasses
...
so I can just select the correct task in my IDE or run all of them in my build pipeline.
I found some hints on the web, that you can use something like this:
dependencies {
testImplementation group: 'org.mycorp.exmpl', name: 'redis-backend', version: '0.0.1', configuration: 'redis'
testImplementation group: 'org.mycorp.exmpl', name: 'mongo-backend', version: '0.0.1', configuration: 'mongo'
}
But thats about where I stopped finding/understanding.
(As you might notice, I am a gradle novice)

Answer 1

Try something alike:
./gradlew test -Dbackend=redis
dependencies {
if (System.getProperty("backend") == "redis") {
implementation "org.mycorp.exmpl:redis-backend:0.0.1"
} else {
implementation "org.mycorp.exmpl:mongo-backend:0.0.1"
}
}
Or even:
./gradlew test -Dbackend=redis-backend:0.0.1
implementation "org.mycorp.exmpl:${System.getProperty("backend")}"
Making it a project property -Pbackend with a default value suggested.
See Environment Options.