Change 'overrides nothing' to report via Message (see #1965) (#1968)

* Change 'overrides nothing' to report via Message, split into two different messages

* Change 'overrides nothing' to report via Message, split into two different messages

1 files changed, 43 insertions, 0 deletions

diff --git a/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala b/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
index f43d559d4..be641fe15 100644
--- a/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
+++ b/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
@@ -42,4 +42,47 @@ class ErrorMessagesTests extends ErrorMessagesTest {
       // is a type reference to `java.lang.String`
       assert(expected.dealias =:= defn.StringType, s"expected was: $expected")
     }
+
+  @Test def overridesNothing =
+    checkMessagesAfter("refchecks") {
+      """
+        |object Foo {
+        |  override def bar: Unit = {}
+        |}
+      """.stripMargin
+    }
+    .expect { (ictx, messages) =>
+      implicit val ctx: Context = ictx
+      val defn = ictx.definitions
+
+      assertMessageCount(1, messages)
+      val OverridesNothing(member) :: Nil = messages
+      assertEquals("bar", member.name.show)
+    }
+
+  @Test def overridesNothingDifferentSignature =
+    checkMessagesAfter("refchecks") {
+      """
+        |class Bar {
+        |  def bar(s: String): Unit = {}
+        |  def bar(s: Int): Unit = {}
+        |  final def bar(s: Long): Unit = {}
+        |}
+        |object Foo extends Bar {
+        |  override def bar: Unit = {}
+        |}
+      """.stripMargin
+    }
+    .expect { (ictx, messages) =>
+      implicit val ctx: Context = ictx
+      val defn = ictx.definitions
+
+      assertMessageCount(1, messages)
+      val OverridesNothingButNameExists(member, sameName) :: Nil = messages
+      // check expected context data
+      assertEquals("bar", member.name.show)
+      assertEquals(3, sameName.size)
+      assert(sameName.forall(_.symbol.name.show == "bar"),
+        "at least one method had an unexpected name")
+    }
 }