How many ack level are you on?

Don't know if there's a better / more straightforward way to get address
this. Things were working just fine with sbt 0.13. The goal is to simply
get the repo list that sbt uses to resolve the global plugins, but from a
*-build project.

sbt-coursier/src/main/scala/coursier/CoursierPlugin.scala

@@ -79,17 +79,78 @@ object CoursierPlugin extends AutoPlugin {
 
   private val pluginIvySnapshotsBase = Resolver.SbtPluginRepositoryRoot.stripSuffix("/") + "/ivy-snapshots"
 
+  // allows to get the actual repo list when sbt starts up
+  private val hackHack = Seq(
+    // TODO Add docker-based non reg test for that, with sbt-assembly 0.14.5 in ~/.sbt/1.0/plugins/plugins.sbt
+    // along with the required extra repo https://repository.jboss.org/nexus/content/repositories/public
+    // (required for coursier, because of bad checksums on central)
+    appConfiguration.in(updateSbtClassifiers) := {
+      val app = appConfiguration.in(updateSbtClassifiers).value
+
+      // hack to trigger https://github.com/sbt/sbt/blob/v1.0.1/main/src/main/scala/sbt/Defaults.scala#L2856,
+      // to have the third case be used instead of the second one, at https://github.com/sbt/sbt/blob/v1.0.1/main/src/main/scala/sbt/Defaults.scala#L2069
+      // 😃🔫
+      new xsbti.AppConfiguration {
+        def provider() = {
+          val prov = app.provider()
+          new xsbti.AppProvider {
+            def newMain() = prov.newMain()
+            def components() = prov.components()
+            def mainClass() = prov.mainClass()
+            def mainClasspath() = prov.mainClasspath()
+            def loader() = prov.loader()
+            def scalaProvider() = {
+              val scalaProv = prov.scalaProvider()
+              new xsbti.ScalaProvider {
+                def app(id: xsbti.ApplicationID) = scalaProv.app(id)
+                def loader() = scalaProv.loader()
+                def jars() = scalaProv.jars()
+                def libraryJar() = scalaProv.libraryJar()
+                def version() = scalaProv.version()
+                def compilerJar() = scalaProv.compilerJar()
+                def launcher() = {
+                  val launch = scalaProv.launcher()
+                  new xsbti.Launcher {
+                    def app(id: xsbti.ApplicationID, version: String) = launch.app(id, version)
+                    def checksums() = launch.checksums()
+                    def globalLock() = launch.globalLock()
+                    def bootDirectory() = launch.bootDirectory()
+                    def appRepositories() = launch.appRepositories()
+                    def topLoader() = launch.topLoader()
+                    def getScala(version: String) = launch.getScala(version)
+                    def getScala(version: String, reason: String) = launch.getScala(version, reason)
+                    def getScala(version: String, reason: String, scalaOrg: String) = launch.getScala(version, reason, scalaOrg)
+                    def isOverrideRepositories = launch.isOverrideRepositories
+                    def ivyRepositories() =
+                      throw new NoSuchMethodError("nope")
+                    def ivyHome() = launch.ivyHome()
+                  }
+                }
+              }
+            }
+            def entryPoint() = prov.entryPoint()
+            def id() = prov.id()
+          }
+        }
+        def arguments() = app.arguments()
+        def baseDirectory() = app.baseDirectory()
+      }
+    }
+  )
+
   def coursierSettings(
     shadedConfigOpt: Option[(String, String)],
     packageConfigs: Seq[(Configuration, String)]
-  ) = Seq(
+  ) = hackHack ++ Seq(
     coursierResolvers := Tasks.coursierResolversTask.value,
     coursierRecursiveResolvers := Tasks.coursierRecursiveResolversTask.value,
     coursierSbtResolvers := {
 
       // TODO Add docker-based integration test for that, see https://github.com/coursier/coursier/issues/632
 
-      val resolvers = externalResolvers.in(updateSbtClassifiers).value
+      val resolvers =
+        sbt.Classpaths.bootRepositories(appConfiguration.value).toSeq.flatten ++ // required because of the hack above it seems
+          externalResolvers.in(updateSbtClassifiers).value
 
       val pluginIvySnapshotsFound = resolvers.exists {
         case repo: URLRepository =>