1 files changed, 27 insertions, 1 deletions
diff --git a/test/junit/scala/reflect/internal/TypesTest.scala b/test/junit/scala/reflect/internal/TypesTest.scala
index 95194ef0a4..05a77cfb47 100644
--- a/test/junit/scala/reflect/internal/TypesTest.scala
+++ b/test/junit/scala/reflect/internal/TypesTest.scala
@@ -1,9 +1,10 @@
 package scala.reflect.internal
 
 import org.junit.Assert._
-import org.junit.Test
+import org.junit.{Assert, Test}
 import org.junit.runner.RunWith
 import org.junit.runners.JUnit4
+import scala.collection.mutable
 import scala.tools.nsc.symtab.SymbolTableForUnitTesting
 
 @RunWith(classOf[JUnit4])
@@ -32,4 +33,29 @@ class TypesTest {
     val uniquelyNarrowed2 = refinedType(boolWithString1narrow2 :: Nil, NoSymbol)
     assert(uniquelyNarrowed1 =:= uniquelyNarrowed2)
   }
+
+  @Test
+  def testTransitivityWithModuleTypeRef(): Unit = {
+    import rootMirror.EmptyPackageClass
+    val (module, moduleClass) = EmptyPackageClass.newModuleAndClassSymbol(TermName("O"), NoPosition, 0L)
+    val minfo = ClassInfoType(List(ObjectTpe), newScope, moduleClass)
+    module.moduleClass setInfo minfo
+    module setInfo module.moduleClass.tpe
+    val tp1 = TypeRef(ThisType(EmptyPackageClass), moduleClass, Nil)
+    val tp2 = SingleType(ThisType(EmptyPackageClass), module)
+    val tp3 = ThisType(moduleClass)
+    val tps = List(tp1, tp2, tp3)
+    val results = mutable.Buffer[String]()
+    tps.permutations.foreach {
+      case ts @ List(a, b, c) =>
+        def tsShownRaw = ts.map(t => showRaw(t)).mkString(", ")
+        if (a <:< b && b <:< c && !(a <:< c)) results += s"<:< intransitive: $tsShownRaw"
+        if (a =:= b && b =:= c && !(a =:= c)) results += s"=:= intransitive: $tsShownRaw"
+    }
+    results.toList match {
+      case Nil => // okay
+      case xs =>
+        Assert.fail(xs.mkString("\n"))
+    }
+  }
 }