Fix typing upon detuplification

compiler/shared_ast/typing.ml

@@ -786,10 +786,22 @@ and typecheck_expr_top_down :
       List.map2 (typecheck_expr_top_down ~leave_unresolved ctx env) t_args args
     in
     let t_args =
-      match t_args with
+      match t_args, tys with
-      | [t] -> (
+      | [t], [] -> (
+        (* Handles typing before detuplification: if [tys] was not yet set, we
+           are allowed to destruct a tuple into multiple arguments (see
+           [Scopelang.from_desugared] for the corresponding code
+           transformation) *)
         match UnionFind.get t with TTuple tys, _ -> tys | _ -> t_args)
-      | _ -> t_args
+      | _ ->
+        if List.length t_args <> List.length args' then
+          Message.raise_spanned_error (Expr.pos e)
+            (match e1 with
+            | EAbs _, _ -> "This binds %d variables, but %d were provided."
+            | _ -> "This function application has %d arguments, but expects %d.")
+            (List.length t_args) (List.length args');
+
+        t_args
     in
     let t_func = unionfind ~pos:e1 (TArrow (t_args, tau)) in
     let e1' = typecheck_expr_top_down ~leave_unresolved ctx env t_func e1 in

tests/test_func/good/scope_call_func_struct_closure.catala_en

@@ -55,7 +55,7 @@ $ catala Typecheck --check-invariants
 
 ```catala-test-inline
 $ catala Lcalc --avoid-exceptions -O --closure-conversion 
-
+type Eoption =  | ENone of unit  | ESome of any 
 
 type Result = {
   r: ((closure_env, integer) → integer * closure_env);
@@ -76,7 +76,7 @@ type SubFoo2 = {
   y: ((closure_env, integer) → integer * closure_env);
 }
 
-type Foo_in = { b_in: ((any, unit) → eoption bool * any); }
+type Foo_in = { b_in: ((closure_env, unit) → eoption bool * closure_env); }
 
 type Foo = { z: integer; }
  
@@ -125,10 +125,13 @@ let topval closure_r : (closure_env, integer) → integer =
   in
   code_and_env.0 code_and_env.1 param0 
 let scope Foo
-  (Foo_in: Foo_in {b_in: ((any, unit) → eoption bool * any)})
+  (Foo_in:
+     Foo_in {b_in: ((closure_env, unit) → eoption bool * closure_env)})
   : Foo {z: integer}
   =
-  let get b : ((any, unit) → eoption bool * any) = Foo_in.b_in in
+  let get b : ((closure_env, unit) → eoption bool * closure_env) =
+    Foo_in.b_in
+  in
   let set b : bool =
     match
       (handle_default_opt

tests/test_tuples/good/tuples.catala_en

@@ -31,4 +31,13 @@ scope Test:
         f2 of str, Two content (12, str))
 ```
 
-Test in progress
+```catala-test-inline
+$ catala typecheck
+[RESULT] Typechecking successful!
+```
+
+```catala-test-inline
+$ catala interpret -s Test
+[RESULT] Computation successful! Results:
+[RESULT] o = [2001-01-03; 6.0]
+```