4 files changed, 74 insertions, 2 deletions
diff --git a/test/files/pos/infersingle.scala b/test/files/pos/infersingle.scala
index 6830fcd799..60f4ff07e6 100644
--- a/test/files/pos/infersingle.scala
+++ b/test/files/pos/infersingle.scala
@@ -1,5 +1,52 @@
-object Test {
+object Test1 {
   def one[T](x: T): Option[T] = Some(x)
   val x = "one"
   val y: Option[x.type] = one(x)
-}
-\ No newline at end of file
+}
+
+object Test2 {
+  // Has never worked, but seems desirable given the recent changes to
+  // pattern type inference.
+  val a = ""
+  object Id {
+    def unapply(xxxx: Any): Some[a.type] = Some[a.type](a)
+  }
+  val b: a.type = (a: a.type) match {
+    case Id(x) => x
+  }
+}
+
+object Test3 {
+  val a = ""
+  object Id {
+    def unapply(xxxx: Any): Some[Test3.type] = Some[Test3.type](Test3)
+  }
+  val b: Test3.type = a match {
+    case Id(x) => x
+  }
+}
+
+class Test4 {
+  val a = ""
+  object Id {
+    def unapply(xxxx: Any): Some[Test4.this.type] = Some[Test4.this.type](Test4.this)
+  }
+  val b: Test4.this.type = a match {
+    case Id(x) => x
+  }
+}
+
+class Super5 {
+  final val q = ""
+  def q1: q.type = q
+}
+
+class Test5 extends Super5 {
+  val a = ""
+  object Id {
+    def unapply(xxxx: Any): Some[Test5.super.q.type] = Some[Test5.super.q.type](q1)
+  }
+  val b: Test5.super.q.type = a match {
+    case Id(x) => x
+  }
+}
diff --git a/test/files/pos/private-types-after-typer.scala b/test/files/pos/private-types-after-typer.scala
new file mode 100644
index 0000000000..79ef934063
--- /dev/null
+++ b/test/files/pos/private-types-after-typer.scala
@@ -0,0 +1,9 @@
+// Testing that the type of the outer accessor in O2
+// doesn't crash the compiler over private type escaping scope.
+trait T {
+  class C {
+     private object O1 {
+        object O2
+     }
+  }
+}
+\ No newline at end of file
diff --git a/test/files/pos/t7818.scala b/test/files/pos/t7818.scala
new file mode 100644
index 0000000000..77b99e7d5d
--- /dev/null
+++ b/test/files/pos/t7818.scala
@@ -0,0 +1,10 @@
+class Observable1[+T](val asJava: JObservable[_ <: T]) extends AnyVal {
+  private def foo[X](a: JObservable[X]): JObservable[X] = ???
+  // was generating a type error as the type of the RHS included an existential
+  // skolem based on the class type parameter `T`, which did not conform
+  // to the typer parameter of the extension method into which the RHS is
+  // transplanted.
+  def synchronize: Observable1[T] = new Observable1(foo(asJava))
+}
+
+class JObservable[T]
diff --git a/test/files/pos/t7834.scala b/test/files/pos/t7834.scala
new file mode 100644
index 0000000000..fc9a0aa09d
--- /dev/null
+++ b/test/files/pos/t7834.scala
@@ -0,0 +1,6 @@
+class S { val q = "" }
+
+class B extends S {
+  val x1: B.super.q.type = q
+  val x2: B.this.q.type  = q
+}