sbt subproject cannot find it's dependencies - scala

Question

I have a project tree consisting of three projects A, B and C
B depends on A, and C depends on both A and B.
A and B are checked out in C's lib/ and both build fine using sbt compile
However, when I compile C, the build of B fails, complaining that it cannot find certain types/packages:
import org.scalatra.sbt._
import sbt.Keys._
import sbt._
object NwbApiBuild extends Build {
val Organization = "org.nwb"
val Name = "NWB API"
val Version = "0.1.0-SNAPSHOT"
val ScalaVersion = "2.10.3"
val ScalatraVersion = "2.3.0"
lazy val active_slick= Project (
"active-slick",
base = file("lib/active-slick")
)
lazy val slick_auth= Project (
"slick-auth",
base = file("lib/slick-auth")
)
lazy val project = Project (
"root",
file("."),
settings = Defaults.defaultSettings ++ ScalatraPlugin.scalatraWithJRebel ++ Seq(
organization := Organization,
name := Name,
version := Version,
scalaVersion := ScalaVersion,
resolvers += Classpaths.typesafeReleases,
libraryDependencies ++= Seq(
"org.scalatra" %% "scalatra" % ScalatraVersion,
"org.scalatra" %% "scalatra-specs2" % ScalatraVersion % "test",
"ch.qos.logback" % "logback-classic" % "1.0.6" % "runtime",
"org.eclipse.jetty" % "jetty-webapp" % "8.1.8.v20121106" % "container",
"org.eclipse.jetty.orbit" % "javax.servlet" % "3.0.0.v201112011016" % "container;provided;test" artifacts (Artifact("javax.servlet", "jar", "jar")),
"com.typesafe.slick" %% "slick" % "2.0.2",
"mysql" % "mysql-connector-java" % "5.1.31",
"joda-time" % "joda-time" % "2.3",
"org.joda" % "joda-convert" % "1.5",
"com.github.tototoshi" %% "slick-joda-mapper" % "1.1.0",
"org.json4s" %% "json4s-native" % "3.2.10",
"org.json4s" %% "json4s-jackson" % "3.2.7",
"c3p0" % "c3p0" % "0.9.1.2"
)
)
) aggregate(active_slick, slick_auth) dependsOn(active_slick, slick_auth)
}
where slick auth has build file
import org.scalatra.sbt._
name := "slick-auth"
version := "0.0.1-SNAPSHOT"
scalaVersion := "2.10.3"
val ScalatraVersion = "2.3.0"
lazy val active_slick = Project(
"active-slick",
base = file("lib/active-slick")
)
lazy val root = Project(
"root",
file("."),
settings = Defaults.defaultSettings ++ ScalatraPlugin.scalatraSettings ++ Seq(
libraryDependencies ++= Seq(
"com.typesafe.slick" %% "slick" % "2.0.2",
"org.slf4j" % "slf4j-nop" % "1.6.4",
"org.scalatest" %% "scalatest" % "2.2.0" % "test",
"org.scalatra" %% "scalatra" % ScalatraVersion,
"org.scalatra" %% "scalatra-specs2" % ScalatraVersion % "test",
"ch.qos.logback" % "logback-classic" % "1.0.6" % "runtime",
"org.eclipse.jetty" % "jetty-webapp" % "8.1.8.v20121106" % "container",
"org.eclipse.jetty.orbit" % "javax.servlet" % "3.0.0.v201112011016" % "container;provided;test" artifacts (Artifact("javax.servlet", "jar", "jar")),
"com.typesafe.slick" %% "slick" % "2.0.2",
"joda-time" % "joda-time" % "2.3",
"org.joda" % "joda-convert" % "1.5",
"com.github.tototoshi" %% "slick-joda-mapper" % "1.1.0",
"org.json4s" %% "json4s-native" % "3.2.10",
"org.json4s" %% "json4s-jackson" % "3.2.7",
"c3p0" % "c3p0" % "0.9.1.2"
)
)
).aggregate(active_slick).dependsOn(active_slick)
and active_slick:
name := "active-slick"
version := "0.0.1-SNAPSHOT"
scalaVersion := "2.10.3"
libraryDependencies ++= Seq(
"com.typesafe.slick" %% "slick" % "2.0.2",
"org.slf4j" % "slf4j-nop" % "1.6.4",
"org.scalatest" %% "scalatest" % "2.2.0" % "test",
"com.h2database" % "h2" % "1.3.166" % "test"
)

Answer 1

If you want to use another project as a dependency (rather than its binary version) you can use project references. There are two types of references, ProjectRef or a simpler version of the ProjectRef, which is RootProject.
You should change your build definition to reference slick_auth as
lazy val slick_auth = RootProject(file("lib/slick-auth"))
and active_slick as
lazy val active_slick = RootProject(file("lib/active-slick"))