Revert more of a477dc for good measure

We stop failing automatically on non-declared-class nested or toplevel
subgoals as in 8.5, instead of the previous a477dc behavior of shelving
those goals and failing if shelved goals remained at the end of
resolution. It means typeclass resolution during refinement is closer to
all:typeclasses eauto. Hints in typeclass_instances for non-declared
classes can be used during resolution of _nested_ subgoals when it is
fired from type-inference, toplevel goals considered in this case are
still only classes (as in 8.5 and before). The code that triggers the
restriction to only declared class subgoals is commented.

Revert changes to test-suite, adding test for #5203, #5198 is fixed too.

Add corresponding tests in the test-suite (that will break if we,
e.g. disallow non-class subgoals) and update the refman accordingly.

1 files changed, 3 insertions, 3 deletions

diff --git a/test-suite/success/bteauto.v b/test-suite/success/bteauto.v
index 0af367781..3178c6fc1 100644
--- a/test-suite/success/bteauto.v
+++ b/test-suite/success/bteauto.v
@@ -24,9 +24,9 @@ Module Backtracking.
     Fail all:((once (typeclasses eauto with typeclass_instances))
               + apply eq_refl).
     (* Does backtrack if other goals fail *)
-    all:[> (unshelve typeclasses eauto; fail) + reflexivity .. ].
+    all:[> typeclasses eauto + reflexivity .. ].
     Undo 1.
-    all:((unshelve typeclasses eauto; fail) + reflexivity). (* Note "+" is a focussing combinator *)
+    all:(typeclasses eauto + reflexivity). (* Note "+" is a focussing combinator *)
     Show Proof.  
   Qed.
 
@@ -66,7 +66,7 @@ Module Backtracking.
       unshelve evar (t : A). all:cycle 1.
       refine (@ex_intro _ _ t _).
       all:cycle 1.
-      all:((unshelve typeclasses eauto; fail) + reflexivity).
+      all:(typeclasses eauto + reflexivity).
     Qed.      
   End Leivant.
 End Backtracking.