Scala : week2: implement singletonSet, and union

2 files changed, 32 insertions, 3 deletions

diff --git a/Scala/funsets/src/main/scala/funsets/FunSets.scala b/Scala/funsets/src/main/scala/funsets/FunSets.scala
index 594a49d..c6d5ea5 100644
--- a/Scala/funsets/src/main/scala/funsets/FunSets.scala
+++ b/Scala/funsets/src/main/scala/funsets/FunSets.scala
@@ -20,13 +20,13 @@ object FunSets {
   /**
    * Returns the set of the one given element.
    */
-  def singletonSet(elem: Int): Set = ???
+  def singletonSet(elem: Int): Set = (x =>  x == elem)
 
   /**
    * Returns the union of the two given sets,
    * the sets of all elements that are in either `s` or `t`.
    */
-  def union(s: Set, t: Set): Set = ???
+  def union(s: Set, t: Set): Set = (x => s(x) | t(x))
 
   /**
    * Returns the intersection of the two given sets,
diff --git a/Scala/funsets/src/test/scala/funsets/FunSetSuite.scala b/Scala/funsets/src/test/scala/funsets/FunSetSuite.scala
index e75ba8c..e61a56c 100644
--- a/Scala/funsets/src/test/scala/funsets/FunSetSuite.scala
+++ b/Scala/funsets/src/test/scala/funsets/FunSetSuite.scala
@@ -101,7 +101,36 @@ class FunSetSuite extends FunSuite {
     }
   }
 
-  ignore("union contains all elements") {
+  test("singletonSet(1)") {
+    new TestSets {
+      assert(!contains(s1, -1), "fails with -1")
+      assert(!contains(s1, 0), "fails with 0")
+      assert(contains(s1, 1), "fails with 1")
+      assert(!contains(s1, 2), "fails with 2")
+      assert(!contains(s1, 3), "fails with 3")
+    }
+  }
+
+  test("singletonSet(2)") {
+    new TestSets {
+      assert(!contains(s2, -1), "fails with -1")
+      assert(!contains(s2, 0), "fails with 0")
+      assert(!contains(s2, 1), "fails with 1")
+      assert(contains(s2, 2), "fails with 2")
+      assert(!contains(s2, 3), "fails with 3")
+    }
+  }
+  test("singletonSet(3)") {
+    new TestSets {
+      assert(!contains(s3, -1), "fails with -1")
+      assert(!contains(s3, 0), "fails with 0")
+      assert(!contains(s3, 1), "fails with 1")
+      assert(!contains(s3, 2), "fails with 2")
+      assert(contains(s3, 3), "fails with 3")
+    }
+  }
+
+  test("union contains all elements") {
     new TestSets {
       val s = union(s1, s2)
       assert(contains(s, 1), "Union 1")