How to pass project to a task? - sbt

Question

I'm writing a Task that needs access to the Project - it needs to iterate through the dependencies to do some side-effect specific to our build. I need to be able to work out transitive internal and external dependencies (i.e. modules and jars) of children modules of thisProject.
I'm currently doing something like this to pass the other things that I need (name and Ivy-managed deps via libraryDependencies):
myTask := runMyTask(
(name in Compile).value,
(libraryDependencies in Compile).value
)
I still need another parameter like
(project in Compile)
but such a key does not exist.
How am I supposed to get the Project?
NB I realise this is probably not possible - without an evil hack involving named lookup of projects from a manually maintained hashmap - because of the Project/Task/Phase axis, but worth asking anyway in case there is a clean solution.

Answer 1

Use thisProject or any other lazy val that you've defined in the build.
> help thisProject
Provides the current project for the referencing scope.
> inspect thisProject
[info] Setting: sbt.ResolvedProject = Project(id runtime-assembly, base: C:\dev\sandbox\runtime-assembly, configurations: List(compile, runtime, test, provided, optional), plugins: List(<none>), autoPlugins: List(sbt.plugins.CorePlugin, sbt.plugins.IvyPlugin, sbt.plugins.JvmPlugin, sbt.plugins.JUnitXmlReportPlugin))
[info] Description:
[info] Provides the current project for the referencing scope.
[info] Provided by:
[info] {file:/C:/dev/sandbox/runtime-assembly/}runtime-assembly/*:thisProject
[info] Defined at:
[info] (sbt.Load) Load.scala:210
[info] Reverse dependencies:
[info] *:ivyConfigurations
[info] *:name
[info] *:organization
[info] *:cacheDirectory
[info] *:baseDirectory
[info] Delegates:
[info] *:thisProject
[info] {.}/*:thisProject
[info] */*:thisProject
Give it a try in consoleProject as follows:
> consoleProject
[info] Starting scala interpreter...
[info]
import sbt._
import Keys._
import dsl._
import _root_.org.sbtidea.SbtIdeaPlugin._
import _root_.de.johoop.jacoco4sbt.JacocoPlugin._
import _root_.com.timushev.sbt.updates.UpdatesPlugin._
import _root_.sbtassembly.Plugin._
import _root_.sbt.plugins.IvyPlugin
import _root_.sbt.plugins.JvmPlugin
import _root_.sbt.plugins.CorePlugin
import _root_.sbt.plugins.JUnitXmlReportPlugin
import currentState._
import extracted._
import cpHelpers._
Welcome to Scala version 2.10.4 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_60).
Type in expressions to have them evaluated.
Type :help for more information.
scala> thisProject
res0: sbt.SettingKey[sbt.ResolvedProject] = sbt.SettingKey$$anon$4#1f3eff94
scala> thisProject.eval
res1: sbt.ResolvedProject = Project(id runtime-assembly, base: C:\dev\sandbox\runtime-assembly, configurations: List(compile, runtime, test, provided, optional), plugins: List(<none>), autoPlugins: List(sbt.plugins.CorePlugin, sbt.plugins.IvyPlugin, sbt.plugins.JvmPlugin, sbt.plugins.JUnitXmlReportPlugin))
scala> thisProject.eval.dependencies
res2: Seq[sbt.ClasspathDep[sbt.ProjectRef]] = List()
There's also configurations field that holds a list of available configurations for the project. Use it if you need to query for the value of a setting, say libraryDependencies, across configurations.
scala> thisProject.eval.configurations
res3: Seq[sbt.Configuration] = List(compile, runtime, test, provided, optional)
You may also want to read about ScopeFilter in Getting values from multiple scopes "that gets values from multiple scopes". Including a sample from the page:
lazy val core = project
lazy val util = project
lazy val root = project.settings(
sources := {
val filter = ScopeFilter(inProjects(core, util), inConfigurations(Compile))
// each sources definition is of type Seq[File],
// giving us a Seq[Seq[File]] that we then flatten to Seq[File]
val allSources: Seq[Seq[File]] = sources.all(filter).value
allSources.flatten
}
)