7 files changed, 123 insertions, 0 deletions
diff --git a/test/files/pos/t6675.flags b/test/files/pos/t6675.flags
new file mode 100644
index 0000000000..e8fb65d50c
--- /dev/null
+++ b/test/files/pos/t6675.flags
@@ -0,0 +1 @@
+-Xfatal-warnings
+\ No newline at end of file
diff --git a/test/files/pos/t6675.scala b/test/files/pos/t6675.scala
new file mode 100644
index 0000000000..f3bebea5be
--- /dev/null
+++ b/test/files/pos/t6675.scala
@@ -0,0 +1,20 @@
+object LeftOrRight {
+  def unapply[A](value: Either[A, A]): Option[A] = value match {
+    case scala.Left(x) => Some(x)
+    case scala.Right(x) => Some(x)
+  }
+}
+
+object Test {
+  (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match {
+    case LeftOrRight(pair @ (a, b)) => a // false -Xlint warning: "extractor pattern binds a single value to a Product2 of type (Int, Int)"
+  }
+
+  (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match {
+    case LeftOrRight((a, b)) => a // false -Xlint warning: "extractor pattern binds a single value to a Product2 of type (Int, Int)"
+  }
+
+  (Left((0, 0)): Either[(Int, Int), (Int, Int)]) match {
+    case LeftOrRight(a, b) => a // false -Xlint warning: "extractor pattern binds a single value to a Product2 of type (Int, Int)"
+  }
+}
diff --git a/test/files/pos/t7200b.scala b/test/files/pos/t7200b.scala
new file mode 100644
index 0000000000..9d579c6ef9
--- /dev/null
+++ b/test/files/pos/t7200b.scala
@@ -0,0 +1,50 @@
+import language.higherKinds
+
+trait T {
+  def t = 0
+}
+trait Foo {
+  def coflatMap[A <: T](f: A): A
+}
+
+object O extends Foo {
+  def coflatMap[A <: T](f: A) = {
+    val f2 = coflatMap(f) // inferred in 2.9.2 / 2.10.0 as [Nothing]
+    f2.t                  // so this does't type check.
+    f2
+  }
+}
+
+// Why? When a return type is inherited, the derived method
+// symbol first gets a preliminary type assigned, based on the
+//   1) method type of a unique matching super member
+//   2) viewed as a member type of the inheritor (to substitute,
+//      e.g. class type parameters)
+//   3) substituted to replace the super-method's type parameters
+//      with those of the inheritor
+//   4) dissected to take just the return type wrapped in thisMethodType().
+//
+// In Scala 2.10.0 and earlier, this preliminary method type
+//
+//   1) [A#11329 <: <empty>#3.this.T#7068](<param> f#11333: A#11329)A#11329
+//   2) [A#11329 <: <empty>#3.this.T#7068](<param> f#11333: A#11329)A#11329
+//   3) (<param> f#12556: A#11336)A#11336
+//   4) [A#11336 <: <empty>#3.this.T#7068](<param> f#12552: A#11337&0)A#11336
+//
+// The type #4 from the old version is problematic: the parameter is typed with
+// a skolem for the type parameter `A`. It won't be considered to match the
+// method it overrides, instead they are seen as being overloaded, and type inference
+// goes awry (Nothing is inferred as the type argument for the recursive call
+// to coflatMap.
+//
+// The Namers patch adds one step here: it subsitutes the type parameter symbols
+// for the skolems:
+//
+//  https://github.com/scala/scala/commit/b74c33eb#L2R1014
+//
+// So we end up with a method symbol info:
+//
+//   5) [A#11336 <: <empty>#3.this.T#7068](<param> f#12505: A#11336)A#11336
+//
+// This *does* match the method in the super class, and type inference
+// chooses the correct type argument.
+\ No newline at end of file
diff --git a/test/files/pos/t7369.flags b/test/files/pos/t7369.flags
new file mode 100644
index 0000000000..85d8eb2ba2
--- /dev/null
+++ b/test/files/pos/t7369.flags
@@ -0,0 +1 @@
+-Xfatal-warnings
diff --git a/test/files/pos/t7369.scala b/test/files/pos/t7369.scala
new file mode 100644
index 0000000000..2f31c93d29
--- /dev/null
+++ b/test/files/pos/t7369.scala
@@ -0,0 +1,37 @@
+object Test {
+  val X, Y = true
+  (null: Tuple1[Boolean]) match {
+    case Tuple1(X) =>
+    case Tuple1(Y) => // unreachable
+    case _      =>
+  }
+}
+
+
+sealed abstract class B;
+case object True extends B;
+case object False extends B;
+
+object Test2 {
+
+  val X: B = True
+  val Y: B = False
+
+  (null: Tuple1[B]) match {
+    case Tuple1(X) =>
+    case Tuple1(Y) => // no warning
+    case _      =>
+  }
+}
+
+object Test3 {
+  val X, O = true
+  def classify(neighbourhood: (Boolean, Boolean, Boolean)): String = {
+    neighbourhood match {
+      case (X, X, X) => "middle"
+      case (X, X, O) => "right"
+      case (O, X, X) => "left"
+      case _ => throw new IllegalArgumentException("Invalid")
+    }
+  }
+}
+\ No newline at end of file
diff --git a/test/files/pos/xlint1.flags b/test/files/pos/xlint1.flags
new file mode 100644
index 0000000000..7949c2afa2
--- /dev/null
+++ b/test/files/pos/xlint1.flags
@@ -0,0 +1 @@
+-Xlint -Xfatal-warnings
diff --git a/test/files/pos/xlint1.scala b/test/files/pos/xlint1.scala
new file mode 100644
index 0000000000..27936d8b14
--- /dev/null
+++ b/test/files/pos/xlint1.scala
@@ -0,0 +1,13 @@
+package object foo {
+  implicit class Bar[T](val x: T) extends AnyVal {
+    def bippy = 1
+  }
+}
+
+package foo {
+  object Baz {
+    def main(args: Array[String]): Unit = {
+      "abc".bippy
+    }
+  }
+}