Support do while expression (fix #17)

ThoughtWorksInc · Jun 6, 2015 · 4148c33 · 4148c33
1 parent ff27c14
commit 4148c33
Show file tree

Hide file tree

Showing 2 changed files with 67 additions and 2 deletions.
diff --git a/src/main/scala/com/thoughtworks/scalazMonadFactory/Transformer.scala b/src/main/scala/com/thoughtworks/scalazMonadFactory/Transformer.scala
@@ -315,8 +315,28 @@ object Transformer {
                   transform(treeCopy.Block(block, body, Literal(Constant(())))).monad)),
               origin.tpe)
           }
-          case LabelDef(name, params, rhs) => {
-            ???
+          case LabelDef(name1, List(), block@Block(body, If(condition, Apply(Ident(name2), List()), Literal(Constant(())))))
+            if name1 == name2 => {
+            new MonadTree(
+              Block(List(
+                ValDef(Modifiers(), name1, TypeTree(), transform(treeCopy.Block(block, body, Literal(Constant(())))).monad)),
+                Apply(
+                  Apply(
+                    TypeApply(
+                      Select(TypeApply(reify(_root_.scalaz.Bind).tree, List(TypeTree(monadType))), TermName("bind")),
+                      List(TypeTree(typeOf[_root_.scala.Unit]), TypeTree(origin.tpe))),
+                    List(Ident(name1))),
+                  List(
+                    Function(
+                      List(ValDef(Modifiers(PARAM), TermName(c.freshName()), TypeTree(typeOf[_root_.scala.Unit]), EmptyTree)),
+                      Apply(
+                        TypeApply(
+                          Select(TypeApply(reify(_root_.scalaz.Monad).tree, List(TypeTree(monadType))), TermName("whileM_")),
+                          List(TypeTree(origin.tpe))),
+                        List(
+                          transform(condition).monad,
+                          Ident(name1))))))),
+              origin.tpe)
           }
           case EmptyTree | _: Throw | _: Return | _: New | _: Ident | _: Literal | _: Super | _: This | _: TypTree | _: New | _: TypeDef | _: Function | _: DefDef | _: ClassDef | _: ModuleDef | _: Import | _: ImportSelector => {
             new PlainTree(origin, origin.tpe)

diff --git a/src/test/scala/com/thoughtworks/scalazMonadFactory/TransformerTest.scala b/src/test/scala/com/thoughtworks/scalazMonadFactory/TransformerTest.scala
@@ -414,6 +414,51 @@ def testCatch(): Unit = {
     Assert.assertEquals(Some("foo"), optionHead)
   }
 
+  @Test
+  def testIoDoWhile(): Unit = {
+    val transformer = Transformer[IO]
+    import transformer._
+
+    def s = IO("123")
+    var count = 0
+    val io = async {
+      var i = 0
+      do {
+        count += s.length
+        i += 1
+      } while (i < 100)
+      i
+    }
+
+    Assert.assertEquals(100, io.unsafePerformIO())
+
+    Assert.assertEquals(300, count)
+  }
+
+
+  @Test
+  def testDoWhile(): Unit = {
+    import scalaz.std.option._
+
+    val transformer = Transformer[Option]
+    import transformer._
+
+    def s = Some("123")
+    var count = 0
+    val option = async {
+      var i = 0
+      do {
+        count += s.length
+        i += 1
+      } while (i < 0)
+      i
+    }
+
+    Assert.assertEquals(Some(1), option)
+
+    Assert.assertEquals(3, count)
+  }
+
 }