Fixed bug #2999 (destruct was not refreshing universes of what it generalized *)

+ changed printing of universe Type(0) to Set, so not to show that the
implementation starts numbering with Set=Type(0) while documentation uses
Type(0) for the common type of Prop and Set.

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@12956 85f007b7-540e-0410-9357-904b9bb8a0f7

3 files changed, 16 insertions, 2 deletions

diff --git a/kernel/univ.ml b/kernel/univ.ml
index ef2024c7a..0a22733d0 100644
--- a/kernel/univ.ml
+++ b/kernel/univ.ml
@@ -56,7 +56,7 @@ let cmp_univ_level u v = match u,v with
       else compare dp1 dp2
 
 let string_of_univ_level = function
-  | Set -> "0"
+  | Set -> "Set"
   | Level (d,n) -> Names.string_of_dirpath d^"."^string_of_int n
 
 module UniverseLMap =
@@ -603,7 +603,7 @@ let pr_constraints c =
 		     in pp_std ++  pr_uni_level u1 ++ str op_str ++
 			  pr_uni_level u2 ++ fnl () )  c (str "")
 
-(* Dumping constrains to a file *)
+(* Dumping constraints to a file *)
 
 let dump_universes output g =
   let dump_arc _ = function
diff --git a/tactics/tactics.ml b/tactics/tactics.ml
index 51aa86613..41fab4e71 100644
--- a/tactics/tactics.ml
+++ b/tactics/tactics.ml
@@ -2903,6 +2903,7 @@ let apply_induction_with_discharge induct_tac elim indhyps destopt avoid names t
 let apply_induction_in_context hyp0 elim indvars names induct_tac gl =
   let env = pf_env gl in
   let statuslists,lhyp0,indhyps,deps = cook_sign hyp0 indvars env in
+  let deps = List.map (on_pi3 refresh_universes_strict) deps in
   let tmpcl = it_mkNamedProd_or_LetIn (pf_concl gl) deps in
   let dephyps = List.map (fun (id,_,_) -> id) deps in
   let deps_cstr =
diff --git a/test-suite/bugs/closed/shouldsucceed/2299.v b/test-suite/bugs/closed/shouldsucceed/2299.v
new file mode 100644
index 000000000..c0552ca7b
--- /dev/null
+++ b/test-suite/bugs/closed/shouldsucceed/2299.v
@@ -0,0 +1,13 @@
+(* Check that destruct refreshes universes in what it generalizes *)
+
+Section test.
+
+Variable A: Type.
+
+Inductive T: unit -> Type := C: A -> unit -> T tt.
+
+Let unused := T tt.
+
+Goal T tt -> False.
+ intro X.
+ destruct X.