How to execute a Command in Task - sbt

Question

Is it possible to execute a Command in Sbt Task? If so, how? as Command requires a State, how could I obtain one?
I am trying to override a default task, here's what I've tried
dist := {
println("Turning coverage off")
Command.process("coverageOff")
dist.value
}
The signature of Command.process is (string, state) => _
I havent figure out where to get the State

Answer 1

Yes, you can run a command within a task. Here is what I'm currently doing to achieve it. First, define the following method in your build:
/**
* Convert the given command string to a release step action, preserving and invoking remaining commands
* Note: This was copied from https://github.com/sbt/sbt-release/blob/663cfd426361484228a21a1244b2e6b0f7656bdf/src/main/scala/ReleasePlugin.scala#L99-L115
*/
def runCommandAndRemaining(command: String): State => State = { st: State =>
import sbt.complete.Parser
#annotation.tailrec
def runCommand(command: String, state: State): State = {
val nextState = Parser.parse(command, state.combinedParser) match {
case Right(cmd) => cmd()
case Left(msg) => throw sys.error(s"Invalid programmatic input:\n$msg")
}
nextState.remainingCommands.toList match {
case Nil => nextState
case head :: tail => runCommand(head.commandLine, nextState.copy(remainingCommands = tail))
}
}
runCommand(command, st.copy(remainingCommands = Nil)).copy(remainingCommands = st.remainingCommands)
}
Then, just call any command from within a task using the above defined utility, e.g., runCommandAndRemaining("+myProject/publishLocal")(state.value).
In your specific case, it should boil down to
dist := {
val log = streams.value.log
log.debug("Turning coverage off")
runCommandAndRemaining("coverageOff")(state.value)
dist.value
}
Hope this helps!

Answer 2

State can be obtained by evaluating state.value
To access the current State from a task, use the state task as an
input. For example,
myTask := ... state.value ...
and commands can be called within task using Command.process like so
dist := {
println("Turning coverage off")
Command.process("coverageOff", state.value)
dist.value
}

Answer 3

After getting some help from gitter, it's not possible, one can however do the reverse, call a task in a command.
So if your use case is to run a command and a task sequentially (or vice versa), you can do something like this
lazy val newCommand = Command.command("name") { state =>
val newState = Command.process("comandName", state)
// run task
newState
}