aboutsummaryrefslogtreecommitdiff
path: root/tests/run/t3326.scala
diff options
context:
space:
mode:
authorDmitry Petrashko <dmitry.petrashko@gmail.com>2015-05-22 16:07:23 +0200
committerDmitry Petrashko <dmitry.petrashko@gmail.com>2015-05-22 16:07:23 +0200
commit6965b470d433f501203c4e3d77b0919f826691ba (patch)
tree413446f1af3f40bb69499a60066609af6bc38d9f /tests/run/t3326.scala
parent91bb668c5f1b6e5c51dad9b373c9398521508bc3 (diff)
downloaddotty-6965b470d433f501203c4e3d77b0919f826691ba.tar.gz
dotty-6965b470d433f501203c4e3d77b0919f826691ba.tar.bz2
dotty-6965b470d433f501203c4e3d77b0919f826691ba.zip
Enable 440 run tests that pass.
Note that some of them may pass due to several bugs that interfere.
Diffstat (limited to 'tests/run/t3326.scala')
-rw-r--r--tests/run/t3326.scala74
1 files changed, 74 insertions, 0 deletions
diff --git a/tests/run/t3326.scala b/tests/run/t3326.scala
new file mode 100644
index 000000000..5e403794d
--- /dev/null
+++ b/tests/run/t3326.scala
@@ -0,0 +1,74 @@
+
+
+
+import scala.math.Ordering
+
+
+
+/** The heart of the problem - we want to retain the ordering when
+ * using `++` on sorted maps.
+ *
+ * There are 2 `++` overloads - a generic one in traversables and
+ * a map-specific one in `MapLike` - which knows about the ordering.
+ *
+ * The problem here is that the expected return type for the expression
+ * in which `++` appears drives the decision of the overload that needs
+ * to be taken.
+ * The `collection.SortedMap` does not have `++` overridden to return
+ * `SortedMap`, but `immutable.Map` instead.
+ * This is why `collection.SortedMap` used to resort to the generic
+ * `TraversableLike.++` which knows nothing about the ordering.
+ *
+ * To avoid `collection.SortedMap`s resort to the more generic `TraverableLike.++`,
+ * we override the `MapLike.++` overload in `collection.SortedMap` to return
+ * the proper type `SortedMap`.
+ */
+object Test {
+
+ def main(args: Array[String]): Unit = {
+ testCollectionSorted()
+ testImmutableSorted()
+ }
+
+ def testCollectionSorted(): Unit = {
+ import collection._
+ val order = implicitly[Ordering[Int]].reverse
+ var m1: SortedMap[Int, String] = SortedMap.empty[Int, String](order)
+ var m2: SortedMap[Int, String] = SortedMap.empty[Int, String](order)
+
+ m1 += (1 -> "World")
+ m1 += (2 -> "Hello")
+
+ m2 += (4 -> "Bar")
+ m2 += (5 -> "Foo")
+
+ val m3: SortedMap[Int, String] = m1 ++ m2
+
+ println(m1)
+ println(m2)
+ println(m3)
+
+ println(m1 + (3 -> "?"))
+ }
+
+ def testImmutableSorted(): Unit = {
+ import collection.immutable._
+ val order = implicitly[Ordering[Int]].reverse
+ var m1: SortedMap[Int, String] = SortedMap.empty[Int, String](order)
+ var m2: SortedMap[Int, String] = SortedMap.empty[Int, String](order)
+
+ m1 += (1 -> "World")
+ m1 += (2 -> "Hello")
+
+ m2 += (4 -> "Bar")
+ m2 += (5 -> "Foo")
+
+ val m3: SortedMap[Int, String] = m1 ++ m2
+
+ println(m1)
+ println(m2)
+ println(m3)
+
+ println(m1 + (3 -> "?"))
+ }
+}