Move /src/test to /tests

tests/ui/impl-header-lifetime-elision/path-underscore.rs

@@ -0,0 +1,34 @@
+// Test that `impl MyTrait for Foo<'_>` works.
+
+// run-pass
+
+#![allow(warnings)]
+
+trait MyTrait { }
+
+struct Foo<'a> { x: &'a u32 }
+
+impl MyTrait for Foo<'_> {
+}
+
+fn impls_my_trait<T: MyTrait>() { }
+
+fn impls_my_trait_val<T: MyTrait>(_: T) {
+    impls_my_trait::<T>();
+}
+
+fn random_where_clause()
+where for<'a> Foo<'a>: MyTrait { }
+
+fn main() {
+    let x = 22;
+    let f = Foo { x: &x };
+
+    // This type is `Foo<'x>` for a local lifetime `'x`; so the impl
+    // must apply to any lifetime to apply to this.
+    impls_my_trait_val(f);
+
+    impls_my_trait::<Foo<'static>>();
+
+    random_where_clause();
+}