1 files changed, 96 insertions, 0 deletions
diff --git a/tests/pos/approximateUnion.scala b/tests/pos/approximateUnion.scala
new file mode 100644
index 000000000..c3fe0e162
--- /dev/null
+++ b/tests/pos/approximateUnion.scala
@@ -0,0 +1,96 @@
+object approximateUnion {
+
+  trait C[+T]
+  trait D
+  trait E
+  trait X[-T]
+
+  {
+    trait A extends C[A] with D
+    trait B extends C[B] with D
+
+    val coin = true
+    val x = if (coin) new A else new B
+    val y = Some(if (coin) new A else new B)
+
+    val xtest: C[A | B] & D = x
+    val ytest: Some[C[A | B] & D] = y
+  }
+
+  {
+    trait A extends C[X[A]] with D
+    trait B extends C[X[B]] with D with E
+
+    val coin = true
+    val x = if (coin) new A else new B
+    val y = Some(if (coin) new A else new B)
+
+    val xtest: C[X[A & B]] & D = x
+    val ytest: Some[C[X[A & B]] & D] = y
+  }
+}
+
+object approximateUnion2 {
+
+  trait C[T]
+  trait D
+  trait E
+  trait X[-T]
+
+  {
+    trait A extends C[A] with D
+    trait B extends C[B] with D
+
+    val coin = true
+    val x = if (coin) new A else new B
+    val y = Some(if (coin) new A else new B)
+
+    val xtest: C[_ >: A & B <: A | B] & D = x
+    val ytest: Some[C[_ >: A & B <: A | B] & D] = y
+  }
+
+  {
+    trait A extends C[X[A]] with D
+    trait B extends C[X[B]] with D with E
+
+    val coin = true
+    val x = if (coin) new A else new B
+    val y = Some(if (coin) new A else new B)
+
+    val xtest: C[_ >: X[A | B] <: X[A & B]] & D = x
+    val ytest: Some[C[_ >: X[A | B] <: X[A & B]]] = y
+  }
+}
+
+object approximateUnion3 {
+
+  trait C[-T]
+  trait D
+  trait E
+  trait X[-T]
+
+  {
+    trait A extends C[A] with D
+    trait B extends C[B] with D
+
+    val coin = true
+    val x = if (coin) new A else new B
+    val y = Some(if (coin) new A else new B)
+
+    val xtest: C[A & B] & D = x
+    val ytest: Some[C[A & B] & D] = y
+  }
+
+  {
+    trait A extends C[X[A]] with D
+    trait B extends C[X[B]] with D with E
+
+    val coin = true
+    val x = if (coin) new A else new B
+    val y = Some(if (coin) new A else new B)
+
+    val xtest: C[X[A | B]] & D = x
+    val ytest2: Some[C[X[A | B]] & D] = y
+  }
+}
+