Fix bug where tuples are destructured with the members in the wrong order

src/passes/2-simplify/ligodity.ml

@@ -593,14 +593,15 @@ and simpl_declaration : Raw.declaration -> declaration Location.wrap list result
                    if i = (List.length variables) then accesses
                    else
                      let accesses =
-                        build_access_expr :: accesses
+                       build_access_expr :: accesses
                      in
                      gen_access_tuple name ~i: (i + 1) ~accesses
                  in ok (gen_access_tuple name)
                (* TODO: Improve this error message *)
                | other -> fail @@ simplifying_expr other
           in let%bind decls =
-               bind_map_list process_variable (List.combine variables expr_bind_lst)
+               (* TODO: Rewrite the gen_access_tuple so there's no List.rev *)
+               bind_map_list process_variable (List.combine variables (List.rev expr_bind_lst))
           in ok @@ decls
         | PPar {region = _ ; value = { lpar = _ ; inside = pt; rpar = _; } } ->
           (* Extract parenthetical multi-bind *)

src/test/contracts/let_multiple.mligo

@@ -11,4 +11,4 @@ let main_paren (p: unit) : int = x + y
 let foobar : (int * int) = (23 , 42)
 let (foo : int) , (bar : int) = foobar
 
-let non_tuple_rhs (p: unit) : int = foo + bar
+let non_tuple_rhs (p: unit) : int = bar - foo 

src/test/integration_tests.ml

@@ -1215,7 +1215,7 @@ let mligo_let_multiple () : unit result =
   in
   let%bind () =
     let input = e_unit () in
-    let expected = e_int 65 in
+    let expected = e_int 19 in
     expect_eq program "non_tuple_rhs" input expected
   in
   ok ()