1 files changed, 32 insertions, 0 deletions
diff --git a/tests/run/t7269.scala b/tests/run/t7269.scala
new file mode 100644
index 000000000..d6e11f4f7
--- /dev/null
+++ b/tests/run/t7269.scala
@@ -0,0 +1,32 @@
+import scala.collection.JavaConversions._
+import scala.collection.mutable
+
+object Test extends dotty.runtime.LegacyApp {
+
+  def testMap(): Unit = {
+    val mapJ = new java.util.HashMap[Int, String]
+    val mapS: mutable.Map[Int, String] = mapJ
+
+    (10 to 20).foreach(i => mapS += ((i, i.toString)))
+    assert(11 == mapS.size)
+
+    // ConcurrentModificationException thrown in the following line
+    mapS.retain((i, str) => i % 2 == 0)
+    assert(6 == mapS.size)
+  }
+
+  def testSet(): Unit = {
+    val mapJ = new java.util.HashSet[Int]
+    val mapS: mutable.Set[Int] = mapJ
+
+    (10 to 20).foreach(i => mapS += i)
+    assert(11 == mapS.size)
+
+    // ConcurrentModificationException thrown in the following line
+    mapS.retain((i) => i % 2 == 0)
+    assert(6 == mapS.size)
+  }
+
+  testSet()
+  testMap()
+}