Any way to print the task graph before Gradle actually performs the task?

Question

Not exactly a newb but am trying to dig a big deeper and understand a bit better ... just thought it might be a nice idea to do this.

Answer 1

Thanks to Opal I did this:

gradle.taskGraph.whenReady {taskGraph ->
    println "Tasks"
    taskGraph.getAllTasks().eachWithIndex{ task, n ->
        println "${n + 1} $task"
        task.dependsOn.eachWithIndex{ depObj, m ->
            println "  ${ m + 1 } $depObj"
        }
    }
} 

Output for a Java build:

Tasks
1 task ':compileJava'
2 task ':processResources'
3 task ':classes'
  1 compileJava
  2 dirs
  3 processResources
4 task ':jar'
5 task ':assemble'
  1 org.gradle.api.internal.artifacts.DefaultPublishArtifactSet$ArtifactsTaskDependency@48db7705
6 task ':compileTestJava'
7 task ':processTestResources'
8 task ':testClasses'
  1 processTestResources
  2 dirs
  3 compileTestJava
9 task ':test'
10 task ':check'
  1 value: task ':test'
11 task ':build'
  1 check
  2 assemble

For me, as a Gradle neophyte (one up from a newb), this is great! Although it leaves me slightly puzzled:

1) "build" depends only on "check" and "assemble", and these have 1 dependency each, each with no dependencies. So how does it know to run all the other tasks (which obviously it has to)... I must be missing something.

2) what is dependency "dirs" and "org.gradle.api.internal.artifacts.DefaultPublishArtifactSet$ArtifactsTaskDependency@48db7705"? More importantly, where does these actually come from? getDependsOn() returns a Set<Object> so these may be something other than Tasks.

Plenty to investigate...

Answer 2

The gradle-taskinfo plugin probably does just what Opal describes in his answer.
I wrote it, so I might be biased, but I use it a lot and it works great for me. 😊
Maybe it saves you some time coding!