Get resolvers from inter-project dependencies too

The idea was suggested to me a few days at Scala Up North, by
@MasseGuillaume or @djspiewak, IIRC

Should fix a few test cases more from
https://gist.github.com/paulp/62eaca1850904137959ad9121cce6b15

plugin/src/main/scala-2.10/coursier/CoursierPlugin.scala

@@ -21,6 +21,7 @@ object CoursierPlugin extends AutoPlugin {
     val mavenProfiles = Keys.mavenProfiles
     val coursierSourceRepositories = Keys.coursierSourceRepositories
     val coursierResolvers = Keys.coursierResolvers
+    val coursierRecursiveResolvers = Keys.coursierRecursiveResolvers
     val coursierSbtResolvers = Keys.coursierSbtResolvers
     val coursierUseSbtCredentials = Keys.coursierUseSbtCredentials
     val coursierCredentials = Keys.coursierCredentials
@@ -68,6 +69,7 @@ object CoursierPlugin extends AutoPlugin {
     mavenProfiles := Set.empty,
     coursierSourceRepositories := Nil,
     coursierResolvers <<= Tasks.coursierResolversTask,
+    coursierRecursiveResolvers <<= Tasks.coursierRecursiveResolversTask,
     coursierSbtResolvers <<= externalResolvers in updateSbtClassifiers,
     coursierUseSbtCredentials := false,
     coursierCredentials := Map.empty,

plugin/src/main/scala-2.10/coursier/Keys.scala

@@ -24,6 +24,7 @@ object Keys {
 
   val coursierSourceRepositories = SettingKey[Seq[File]]("coursier-source-repositories")
   val coursierResolvers = TaskKey[Seq[Resolver]]("coursier-resolvers")
+  val coursierRecursiveResolvers = TaskKey[Seq[Resolver]]("coursier-recursive-resolvers", "Resolvers of the current project, plus those of all from its inter-dependency projects")
   val coursierSbtResolvers = TaskKey[Seq[Resolver]]("coursier-sbt-resolvers")
   val coursierUseSbtCredentials = SettingKey[Boolean]("coursier-use-sbt-credentials")
   val coursierCredentials = TaskKey[Map[String, Credentials]]("coursier-credentials")

plugin/src/main/scala-2.10/coursier/Tasks.scala

@@ -69,6 +69,19 @@ object Tasks {
       }
     }
 
+  def coursierRecursiveResolversTask: Def.Initialize[sbt.Task[Seq[Resolver]]] =
+    (
+      sbt.Keys.state,
+      sbt.Keys.thisProjectRef
+    ).flatMap { (state, projectRef) =>
+
+      val projects = allRecursiveInterDependencies(state, projectRef)
+
+      coursierResolvers
+        .forAllProjects(state, projectRef +: projects)
+        .map(_.values.toVector.flatten)
+    }
+
   def coursierFallbackDependenciesTask: Def.Initialize[sbt.Task[Seq[(Module, String, URL, Boolean)]]] =
     (
       sbt.Keys.state,
@@ -383,7 +396,7 @@ object Tasks {
         if (sbtClassifiers)
           coursierSbtResolvers.value
         else
-          coursierResolvers.value
+          coursierRecursiveResolvers.value.distinct
 
       val sourceRepositories = coursierSourceRepositories.value.map { dir =>
         // FIXME Don't hardcode this path?

plugin/src/sbt-test/sbt-coursier/inter-project-resolvers/a/src/main/scala/A.scala

@@ -0,0 +1,6 @@
+
+case class A(msg: String)
+
+object A {
+  def default = A("OK")
+}

plugin/src/sbt-test/sbt-coursier/inter-project-resolvers/b/src/main/scala/Main.scala

@@ -0,0 +1,14 @@
+import java.io.File
+import java.nio.file.Files
+
+import scalaz.stream._
+import scalaz.concurrent.Task
+
+object Main extends App {
+
+  val pch = Process.constant((i:Int) => Task.now(())).take(3)
+  val count = Process.constant(1).toSource.to(pch).runLog.run.size
+  assert(count == 3)
+
+  Files.write(new File("output").toPath, A.default.msg.getBytes("UTF-8"))
+}

plugin/src/sbt-test/sbt-coursier/inter-project-resolvers/build.sbt

@@ -0,0 +1,30 @@
+
+lazy val a = project
+  .settings(sharedSettings)
+  .settings(
+    resolvers += "Scalaz Bintray Repo" at "https://dl.bintray.com/scalaz/releases"
+  )
+
+lazy val b = project
+  .dependsOn(a)
+  .settings(sharedSettings)
+  .settings(
+    // resolver added in inter-project dependency only - should still be fine
+    libraryDependencies += "org.scalaz.stream" %% "scalaz-stream" % "0.7.1a"
+  )
+
+lazy val root = project
+  .in(file("."))
+  .aggregate(a, b)
+  .settings(sharedSettings)
+
+
+lazy val sharedSettings = Seq(
+  scalaVersion := "2.11.8",
+  coursierCachePolicies := {
+    if (sys.props("os.name").startsWith("Windows"))
+      coursierCachePolicies.value
+    else
+      Seq(coursier.CachePolicy.ForceDownload)
+  }
+)

plugin/src/sbt-test/sbt-coursier/inter-project-resolvers/project/plugins.sbt

@@ -0,0 +1,11 @@
+{
+  val pluginVersion = sys.props.getOrElse(
+    "plugin.version",
+    throw new RuntimeException(
+      """|The system property 'plugin.version' is not defined.
+         |Specify this property using the scriptedLaunchOpts -D.""".stripMargin
+    )
+  )
+
+  addSbtPlugin("io.get-coursier" % "sbt-coursier" % pluginVersion)
+}

plugin/src/sbt-test/sbt-coursier/inter-project-resolvers/test

@@ -0,0 +1,3 @@
+$ delete output
+> b/run
+$ exists output