fix repl from sbt

build.sbt

@@ -166,6 +166,7 @@ lazy val root: Project = Project(
 ).settings(
   unidocProjectFilter in (ScalaUnidoc, unidoc) := inAnyProject
     -- inProjects(scioRepl) -- inProjects(scioSchemas) -- inProjects(scioExamples),
+  run <<= run in Compile in scioRepl,
   aggregate in assembly := false
 ).aggregate(
   scioCore,
@@ -344,6 +345,16 @@ lazy val scioRepl: Project = Project(
         Nil
     )
   )
+).settings(
+    mainClass in (Compile,run) := {
+      if (scalaVersion.value.startsWith("2.10")) {
+        throw new UnsupportedOperationException(
+          "\n\n\tERROR: Can't start Scio REPL in SBT for scala 2.10.x. " +
+            "Upgrade to 2.11.x. or build REPL assembly jar.\n" +
+            "\tMore info https://github.com/spotify/scio/wiki/Scio-REPL\n\n")
+      }
+      Some("com.spotify.scio.repl.ScioShell")
+    }
 ).settings(
   assemblyJarName in assembly := s"scio-repl-${version.value}.jar"
 ).dependsOn(

scio-repl/src/main/scala/com/spotify/scio/repl/ScioShell.scala

@@ -17,6 +17,8 @@
 
 package com.spotify.scio.repl
 
+import scala.reflect.io.File
+import scala.tools.nsc.util.ClassPath
 import scala.tools.nsc.{GenericRunnerCommand, MainGenericRunner}
 
 /**
@@ -35,19 +37,41 @@ trait BaseScioShell extends MainGenericRunner {
    * @param args passed from the command line
    * @return `true` if execution was successful, `false` otherwise
    */
+  // scalastyle:off method.length
   override def process(args: Array[String]): Boolean = {
     // Process command line arguments into a settings object, and use that to start the REPL.
     // We ignore params we don't care about - hence error function is empty
     val command = new GenericRunnerCommand(args.toList, _ => ())
 
-    // if running from the assembly, need to explicitly tell it to use java classpath
-    command.settings.usejavacp.value = true
-    command.settings.classpath.append(System.getProperty("java.class.path"))
+    // For scala 2.10 - usejavacp
+    if (scala.util.Properties.versionString.contains("2.10.")) {
+      command.settings.classpath.append(System.getProperty("java.class.path"))
+      command.settings.usejavacp.value = true
+    }
+
+    def classLoaderURLs(cl: ClassLoader): Array[java.net.URL] = cl match {
+      case null => Array()
+      case u: java.net.URLClassLoader => u.getURLs ++ classLoaderURLs(cl.getParent)
+      case _ => classLoaderURLs(cl.getParent)
+    }
+
+    classLoaderURLs(Thread.currentThread().getContextClassLoader)
+      .foreach(u => command.settings.classpath.append(u.getPath))
+
+    // We have to make sure that scala macros are expandable. paradise plugin has to be added to
+    // -Xplugin paths. In case of assembly - paradise is included in assembly jar - thus we add
+    // itself to -Xplugin. If shell is started from sbt or classpath, paradise jar has to be in
+    // classpath, we find it and add it to -Xplugin.
 
     // Repl assembly includes paradise's scalac-plugin.xml - required for BigQuery macro
+    // There should be no harm if we keep this for sbt launch.
     val thisJar = this.getClass.getProtectionDomain.getCodeSource.getLocation.getPath
     command.settings.plugin.appendToValue(thisJar)
 
+    ClassPath.split(command.settings.classpath.value)
+      .find(File(_).name.startsWith("paradise_"))
+      .foreach(command.settings.plugin.appendToValue)
+
     // Useful settings for for debugging, dumping class files etc:
     /* command.settings.debug.value = true
     command.settings.Yreploutdir.tryToSet(List(""))
@@ -56,7 +80,9 @@ trait BaseScioShell extends MainGenericRunner {
     // Force the repl to be synchronous, so all cmds are executed in the same thread
     command.settings.Yreplsync.value = true
 
-    val scioClassLoader = new ScioReplClassLoader(command.settings.classpathURLs.toArray,
+    val scioClassLoader = new ScioReplClassLoader(
+      command.settings.classpathURLs.toArray ++
+        classLoaderURLs(Thread.currentThread().getContextClassLoader),
       null,
       Thread.currentThread.getContextClassLoader)
 
@@ -65,10 +91,12 @@ trait BaseScioShell extends MainGenericRunner {
 
     // Set classloader chain - expose top level abstract class loader down
     // the chain to allow for readObject and latestUserDefinedLoader
+    // See https://gist.github.com/harrah/404272
     command.settings.embeddedDefaults(scioClassLoader)
 
     repl.process(command.settings)
   }
+  // scalastyle:on method.length
 
   /** Runs an instance of the shell. */
   def main(args: Array[String]) {