1 files changed, 75 insertions, 0 deletions
diff --git a/main/test/src/define/CacherTests.scala b/main/test/src/define/CacherTests.scala
new file mode 100644
index 00000000..59ebf3f6
--- /dev/null
+++ b/main/test/src/define/CacherTests.scala
@@ -0,0 +1,75 @@
+package mill.define
+
+import mill.util.{DummyLogger, TestEvaluator, TestUtil}
+import mill.util.Strict.Agg
+import mill.T
+import mill.api.Result.Success
+import utest._
+import utest.framework.TestPath
+
+
+object CacherTests extends TestSuite{
+  object Base extends Base
+  trait Base extends TestUtil.BaseModule{
+    def value = T{ 1 }
+    def result = T{ Success(1) }
+  }
+  object Middle extends Middle
+  trait Middle extends Base{
+    override def value = T{ super.value() + 2}
+    def overriden = T{ super.value()}
+  }
+  object Terminal extends  Terminal
+  trait Terminal extends Middle{
+    override def value = T{ super.value() + 4}
+  }
+
+  val tests = Tests{
+    def eval[T <: TestUtil.BaseModule, V](mapping: T, v: Task[V])
+                                         (implicit tp: TestPath) = {
+      val evaluator = new TestEvaluator(mapping)
+      evaluator(v).right.get._1
+    }
+    def check(x: Any, y: Any) = assert(x == y)
+
+    'simpleDefIsCached - {
+      Predef.assert(Base.value eq Base.value)
+      Predef.assert(eval(Base, Base.value) == 1)
+    }
+
+    'resultDefIsCached - {
+      Predef.assert(Base.result eq Base.result)
+      Predef.assert(eval(Base, Base.result) == 1)
+    }
+
+
+    'overridingDefIsAlsoCached - {
+      Predef.assert(eval(Middle, Middle.value) == 3)
+      Predef.assert(Middle.value eq Middle.value)
+    }
+
+    'overridenDefRemainsAvailable - {
+      Predef.assert(eval(Middle, Middle.overriden) == 1)
+    }
+
+
+    'multipleOverridesWork- {
+      Predef.assert(eval(Terminal, Terminal.value) == 7)
+      Predef.assert(eval(Terminal, Terminal.overriden) == 1)
+    }
+    //    Doesn't fail, presumably compileError doesn't go far enough in the
+    //    compilation pipeline to hit the override checks
+    //
+    //    'overrideOutsideModuleFails - {
+    //      compileError("""
+    //        trait Foo{
+    //          def x = 1
+    //        }
+    //        object Bar extends Foo{
+    //          def x = 2
+    //        }
+    //      """)
+    //    }
+  }
+}
+