Parboiled2 causes "missing or invalid dependency detected while loading class file 'Prepender.class'"

Question

So I've been trying to use parboiled2 for the last few weeks now, it is possibly the most difficult dependency to add to a build I have come across in my entire life. My current error is a compile sbt assembly) error:

[error] missing or invalid dependency detected while loading class file 'Prepender.class'.
[error] Could not access type PrependAux in package shapeless,
[error] because it (or its dependencies) are missing. Check your build definition for
[error] missing or conflicting dependencies. (Re-run with `-Ylog-classpath` to see the problematic classpath.)
[error] A full rebuild may help if 'Prepender.class' was compiled against an incompatible version of shapeless.
[error] .../Main.scala:56: could not find implicit value for parameter prepender: spray.routing.Prepender[shapeless.HNil,shapeless.::[String,shapeless.HNil]]
[error]     path(searchSegment / Segment)(title => get(responder(complete(
[error]                        ^

It seems that it is simply impossible to make Spray and Parboiled2 play nice together.

I've tried sbt clean and removing my target directories. My build file is basically this:

resolvers ++= Seq(
  "spray repo" at "http://repo.spray.io"
)

val akkaV = "2.3.6"
val sprayV = "1.3.2"

libraryDependencies ++= Seq(
  // If I comment this line, everything works fine.
  "org.parboiled" %% "parboiled" % "2.0.1" withSources() withJavadoc(),
  //
  "org.scalacheck" %% "scalacheck" % "1.12.1" % "test" withSources() withJavadoc(),
  "org.specs2" %% "specs2-core" % "2.4.15" % "test" withSources() withJavadoc(),
  "org.specs2" %% "specs2-scalacheck" % "2.4.15" % "test" withSources() withJavadoc(),
  "org.scalaz" %% "scalaz-core" % "7.1.0" withSources() withJavadoc(),
  //
  "io.spray" %% "spray-json" % "1.3.1" withSources() withJavadoc(),
  "io.spray" %% "spray-can" % sprayV withSources() withJavadoc(),
  "io.spray" %% "spray-routing" % sprayV withSources() withJavadoc(),
  "io.spray" %% "spray-testkit" % sprayV  % "test" withSources() withJavadoc(),
  //
  "com.typesafe.akka" %% "akka-actor" % akkaV withSources() withJavadoc(),
  "com.typesafe.akka" %% "akka-testkit" % akkaV % "test" withSources() withJavadoc()
)

scalaVersion := "2.11.4"

javaOptions ++= Seq("-target", "1.8", "-source", "1.8")

My sbtVersion is 0.13.6, and my sbt-assembly version is 0.12.0

Before upgrading to 2.11 and upgrading my specs2 dependencies I got: parboiled2 and Spray cause conflicting cross-version suffixes

Answer 1

If you want to use shapeless2 you need to depend on spray-routing-shapeless2 instead of spray-routing.

See the example dependency declaration:

https://github.com/spray/spray-template/blob/on_spray-can_1.3_shapeless2_scala-2.11/build.sbt