Flesh out a principled implementation of the cross-build monad

1 files changed, 128 insertions, 37 deletions

diff --git a/core/src/test/scala/mill/CrossTests.scala b/core/src/test/scala/mill/CrossTests.scala
index d39072c5..76cde1e9 100644
--- a/core/src/test/scala/mill/CrossTests.scala
+++ b/core/src/test/scala/mill/CrossTests.scala
@@ -6,45 +6,136 @@ import utest._
 object CrossTests extends TestSuite{
 
   val tests = Tests{
-    'test - {
-      Cross.test()
+
+    def assertEquals[T](value: Cross[T], value1: Cross[T]) = {
+      assert(value == value1)
     }
-//    def assertEquals[T](value: Cross[T], value1: Cross[T]) = {
-//      assert(value == value1)
-//    }
-//    'map - assertEquals(
-//      for(a <- Cross(1, 2, 3)) yield a.toString,
-//      Cross(1 -> "1", 2 -> "2", 3 -> "3")
-//    )
-//    'flatMapFilter - assertEquals(
-//      for{
-//        a <- Cross(1, 2)
-//        b <- Cross("A", "B")
-//        if !(a == 2 && b == "B")
-//      } yield b * a,
-//      Cross(
-//        (1 -> ("A" -> "A")),
-//        (1 -> ("B" -> "B")),
-//        (2 -> ("A" -> "AA"))
-//      )
-//    )
-//    'reuse - {
-//      val matrix = for{
-//        a <- Cross(1, 2)
-//        b <- Cross("A", "B")
-//        if !(a == 2 && b == "B")
-//      } yield ()
-//      assertEquals(
-//        for((a, (b, _)) <- matrix)
-//        yield b * a,
-//        Cross(
-//          (1 -> ("A" -> "A")),
-//          (1 -> ("B" -> "B")),
-//          (2 -> ("A" -> "AA"))
-//        )
-//      )
-//    }
+    'single - assertEquals(
+      for(a <- Cross(1, 2, 3)) yield a.toString,
+      Cross(List((List(1), "1"), (List(2), "2"), (List(3), "3")))
+    )
+
+
+
+    'double - assertEquals(
+      for{
+        a <- Cross(1, 2, 3)
+        b <- Cross("A", "B", "C")
+      } yield b * a,
+      Cross(
+        List(
+          (List("A", 1), "A"),
+          (List("B", 1), "B"),
+          (List("C", 1), "C"),
+          (List("A", 2), "AA"),
+          (List("B", 2), "BB"),
+          (List("C", 2), "CC"),
+          (List("A", 3), "AAA"),
+          (List("B", 3), "BBB"),
+          (List("C", 3), "CCC")
+        )
+      )
+    )
+
+
+    'triple - assertEquals(
+      for{
+        a <- Cross(1, 2)
+        b <- Cross("A", "B")
+        c <- Cross(true, false)
+      } yield b * a + c,
+      Cross(
+        List(
+          (List(true, "A", 1), "Atrue"),
+          (List(false, "A", 1), "Afalse"),
+          (List(true, "B", 1), "Btrue"),
+          (List(false, "B", 1), "Bfalse"),
+          (List(true, "A", 2), "AAtrue"),
+          (List(false, "A", 2), "AAfalse"),
+          (List(true, "B", 2), "BBtrue"),
+          (List(false, "B", 2), "BBfalse")
+        )
+      )
+    )
+
+
+    'filter - assertEquals(
+      for{
+        a <- Cross(1, 2, 3)
+        b <- Cross("A", "B", "C")
+        if !(a == 2 && b == "B")
+      } yield b * a,
+      Cross(
+        List(
+          (List("A", 1), "A"),
+          (List("B", 1), "B"),
+          (List("C", 1), "C"),
+          (List("A", 2), "AA"),
+          (List("C", 2), "CC"),
+          (List("A", 3), "AAA"),
+          (List("B", 3), "BBB"),
+          (List("C", 3), "CCC")
+        )
+      )
+    )
+
+
+    'middleFilter- assertEquals(
+      for{
+        a <- Cross(1, 2, 3)
+        if a != 2
+        b <- Cross("A", "B", "C")
+      } yield b * a,
+      Cross(
+        List(
+          (List("A", 1), "A"),
+          (List("B", 1), "B"),
+          (List("C", 1), "C"),
+          (List("A", 3), "AAA"),
+          (List("B", 3), "BBB"),
+          (List("C", 3), "CCC")
+        )
+      )
+    )
+
+
+    'nestedComprehension1 - assertEquals(
+      for{
+        (a, b) <- for(a <- Cross(1, 2); b <- Cross("A", "B")) yield (a, b)
+        c <- Cross(true, false)
+      } yield b * a + c,
+      Cross(
+        List(
+          (List(true, "A", 1), "Atrue"),
+          (List(false, "A", 1), "Afalse"),
+          (List(true, "B", 1), "Btrue"),
+          (List(false, "B", 1), "Bfalse"),
+          (List(true, "A", 2), "AAtrue"),
+          (List(false, "A", 2), "AAfalse"),
+          (List(true, "B", 2), "BBtrue"),
+          (List(false, "B", 2), "BBfalse")
+        )
+      )
+    )
 
+    'nestedComprehension2 - assertEquals(
+      for{
+        a <- Cross(1, 2)
+        (b, c) <- for(b <- Cross("A", "B"); c <- Cross(true, false)) yield (b, c)
+      } yield b * a + c,
+      Cross(
+        List(
+          (List(true, "A", 1), "Atrue"),
+          (List(false, "A", 1), "Afalse"),
+          (List(true, "B", 1), "Btrue"),
+          (List(false, "B", 1), "Bfalse"),
+          (List(true, "A", 2), "AAtrue"),
+          (List(false, "A", 2), "AAfalse"),
+          (List(true, "B", 2), "BBtrue"),
+          (List(false, "B", 2), "BBfalse")
+        )
+      )
+    )
 
   }
 }