Merge pull request #3119 from dotty-staging/implicit-divergence-test

Add test for implicit divergence

Author: allanrenucci

tests/neg/implicitDivergenc.scala

@@ -0,0 +1,13 @@
+object Test {
+  class C[T]
+  implicit def fGen[T](implicit ev: T): C[T] = ???
+  implicit def fString(implicit ev: C[Int]): C[String] = ???
+  implicit def fInt: C[Int] = ???
+
+  implicitly[C[String]]
+  implicitly[C[C[String]]]
+  implicitly[C[C[C[String]]]]
+  implicitly[C[C[C[C[String]]]]]
+  implicitly[C[C[C[C[C[String]]]]]]
+  implicitly[C[C[C[C[C[C[String]]]]]]] // error: no implicit argument found (because of divergence)
+}