Move /src/test to /tests

tests/ui/impl-trait/impl-generic-mismatch-ab.rs

@@ -0,0 +1,12 @@
+use std::fmt::Debug;
+
+trait Foo {
+    fn foo<A: Debug>(&self, a: &A, b: &impl Debug);
+}
+
+impl Foo for () {
+    fn foo<B: Debug>(&self, a: &impl Debug, b: &B) { }
+    //~^ ERROR method `foo` has an incompatible type for trait
+}
+
+fn main() {}