use the correct subtyping order in a test

also, ensure that callers are checked.

Author: arielb1

src/test/compile-fail/wf-static-method.rs

@@ -8,30 +8,57 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// check that static methods don't get to assume `Self` is well-formed
+// check that static methods don't get to assume their trait-ref
+// is well-formed.
+// FIXME(#27579): this is just a bug. However, our checking with
+// static inherent methods isn't quite working - need to
+// fix that before removing the check.
 
-trait Foo<'a, 'b>: Sized {
+trait Foo<'a, 'b, T>: Sized {
     fn make_me() -> Self { loop {} }
-    fn static_evil(u: &'a u32) -> &'b u32;
+    fn static_evil(u: &'b u32) -> &'a u32;
 }
 
 struct Evil<'a, 'b: 'a>(Option<&'a &'b ()>);
 
-impl<'a, 'b> Foo<'a, 'b> for Evil<'a, 'b> {
-    fn make_me() -> Self { Evil(None) }
-    fn static_evil(u: &'a u32) -> &'b u32 {
+impl<'a, 'b> Foo<'a, 'b, Evil<'a, 'b>> for () {
+    fn make_me() -> Self { }
+    fn static_evil(u: &'b u32) -> &'a u32 {
         u //~ ERROR cannot infer an appropriate lifetime
     }
 }
 
 struct IndirectEvil<'a, 'b: 'a>(Option<&'a &'b ()>);
 
-impl<'a, 'b> Foo<'a, 'b> for IndirectEvil<'a, 'b> {
+impl<'a, 'b> Foo<'a, 'b, ()> for IndirectEvil<'a, 'b> {
     fn make_me() -> Self { IndirectEvil(None) }
-    fn static_evil(u: &'a u32) -> &'b u32 {
+    fn static_evil(u: &'b u32) -> &'a u32 {
         let me = Self::make_me(); //~ ERROR lifetime bound not satisfied
         loop {} // (`me` could be used for the lifetime transmute).
     }
 }
 
+impl<'a, 'b> Evil<'a, 'b> {
+    fn inherent_evil(u: &'b u32) -> &'a u32 {
+        u //~ ERROR cannot infer an appropriate lifetime
+    }
+}
+
+// while static methods don't get to *assume* this, we still
+// *check* that they hold.
+
+fn evil<'a, 'b>(b: &'b u32) -> &'a u32 {
+    <()>::static_evil(b) //~ ERROR cannot infer an appropriate lifetime
+}
+
+fn indirect_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
+    <IndirectEvil>::static_evil(b)
+    //~^ ERROR cannot infer an appropriate lifetime
+}
+
+fn inherent_evil<'a, 'b>(b: &'b u32) -> &'a u32 {
+    <Evil>::inherent_evil(b) // bug? shouldn't this be an error
+}
+
+
 fn main() {}