Fix type parameters not getting properly typed

1 files changed, 89 insertions, 0 deletions

diff --git a/dottydoc/test/UsecaseTest.scala b/dottydoc/test/UsecaseTest.scala
index d5f338892..9be688297 100644
--- a/dottydoc/test/UsecaseTest.scala
+++ b/dottydoc/test/UsecaseTest.scala
@@ -52,6 +52,95 @@ class UsecaseTest extends DottyTest {
     }
   }
 
+  @Test def simpleUsecaseAddedArg = {
+    val source = new SourceFile(
+      "DefWithUseCase.scala",
+      """
+      |package scala
+      |
+      |trait Test[A] {
+      |  /** Definition with a "disturbing" signature
+      |   *
+      |   *  @usecase def foo(a: A): A
+      |   */
+      |  def foo[B]: A => B
+      |}
+      """.stripMargin
+    )
+
+    checkSources(source :: Nil) { packages =>
+      packages("scala") match {
+        case PackageImpl(_, _, List(trt: Trait), _, _) =>
+          val List(foo: Def) = trt.members
+
+          val returnValue = foo.returnValue match {
+            case ref: TypeReference => ref.title
+            case _ =>
+              assert(
+                false,
+                "Incorrect return value after usecase transformation"
+              )
+              ""
+          }
+
+          assert(
+            foo.typeParams.isEmpty,
+            "Type parameters were not stripped by usecase"
+          )
+          assert(returnValue == "A", "Incorrect return type after usecase")
+          assert(
+            foo.paramLists.head.list.head.title == "a",
+            "Incorrect parameter to function after usecase transformation"
+          )
+          assert(foo.name == "foo", s"Incorrect name after transform: ${foo.name}")
+      }
+    }
+  }
+
+  @Test def simpleTparamUsecase = {
+    val source = new SourceFile(
+      "DefWithUseCase.scala",
+      """
+      |package scala
+      |
+      |trait Test[A] {
+      |  /** Definition with a "disturbing" signature
+      |   *
+      |   *  @usecase def foo[C]: A
+      |   */
+      |  def foo[B]: A => B
+      |}
+      """.stripMargin
+    )
+
+    checkSources(source :: Nil) { packages =>
+      packages("scala") match {
+        case PackageImpl(_, _, List(trt: Trait), _, _) =>
+          val List(foo: Def) = trt.members
+
+          val returnValue = foo.returnValue match {
+            case ref: TypeReference => ref.title
+            case _ =>
+              assert(
+                false,
+                "Incorrect return value after usecase transformation"
+              )
+              ""
+          }
+
+          assert(
+            foo.typeParams.nonEmpty,
+            "Type parameters were incorrectly stripped by usecase"
+          )
+
+          assert(foo.typeParams.head == "C", "Incorrectly switched tparam")
+          assert(returnValue == "A", "Incorrect return type after usecase")
+
+          assert(foo.name == "foo", s"Incorrect name after transform: ${foo.name}")
+      }
+    }
+  }
+
   @Test def checkIterator = {
     val sources =
       "./scala-scala/src/library/scala/collection/Iterator.scala" :: Nil