pprint.scala

import sbt._, Keys._
import scala.xml.{Node => XmlNode, NodeSeq => XmlNodeSeq, _}
import scala.xml.transform.{RewriteRule, RuleTransformer}
import sbt.plugins.JvmPlugin

object PPrintPlugin extends AutoPlugin {
  override def requires = JvmPlugin
  override def trigger: PluginTrigger = AllRequirements
  override def projectSettings: Seq[Def.Setting[_]] = List(
    libraryDependencies ++= {
      if (scalaVersion.value.startsWith("2."))
        List("com.lihaoyi" %% "pprint" % "0.5.2" % Provided)
      else Nil
    },
    // (optional), if you publish libraries from your local computer then make
    // sure to exclude pprint from your published POM.
    pomPostProcess := { node =>
      new RuleTransformer(new RewriteRule {
        private def isPPrint(node: XmlNode): Boolean = {
          def matchesArtifactId(node: XmlNode) =
            node.label == "artifactId" && node.text.startsWith("pprint_")
          def matchesScope(node: XmlNode) =
            node.label == "scope" && node.text == "provided"
          node.label == "dependency" &&
          node.child.exists(matchesArtifactId) &&
          node.child.exists(matchesScope)
        }
        override def transform(node: XmlNode): XmlNodeSeq = node match {
          case e: Elem if isPPrint(node) => Text("")
          case _ => node
        }
      }).transform(pomPostProcess.value(node)).head
    }
  )
}

Put this in ~/.sbt/0.13/plugins/pprint.scala to use pprint.log everywhere! Very useful for debugging nested data structures

Don't forget to remove the debugging statements before opening a PR

More importantly, don't forget to remove that plugin before publishing any of the projects on your machine. Otherwise a dependency on pprint will leak in the Maven POMs.

This is a terrible idea ...

Good point @sjrd, I agree it's a bad idea if you publish public libraries from a local machine (which I personally do a lot). If you let CI publish artifacts for you or if you don't publish libraries in general then this should be fine.

I updated the gist @sjrd to

• add the dependency to the Provided scope
• add a pomPostProcess to remove any dependency on pprint in the provided scope