Merge branch 'feature/unsupported_ass_None' into 'dev'

Feature/unsupported_ass_none

See merge request ligolang/ligo!118

src/passes/1-parser/pascaligo/AST.ml

@@ -406,9 +406,7 @@ and lhs =
   Path    of path
 | MapPath of map_lookup reg
 
-and rhs =
-      Expr of expr
-| NoneExpr of c_None
+and rhs = expr
 
 and loop =
   While of while_loop reg
@@ -758,9 +756,7 @@ let lhs_to_region : lhs -> Region.t = function
   Path path -> path_to_region path
 | MapPath {region; _} -> region
 
-let rhs_to_region = function
-      Expr e -> expr_to_region e
-| NoneExpr r -> r
+let rhs_to_region = expr_to_region
 
 let selection_to_region = function
   FieldName {region; _}

src/passes/1-parser/pascaligo/AST.mli

@@ -390,9 +390,7 @@ and lhs =
   Path    of path
 | MapPath of map_lookup reg
 
-and rhs =
-      Expr of expr
-| NoneExpr of c_None
+and rhs = expr
 
 and loop =
   While of while_loop reg

src/passes/1-parser/pascaligo/Parser.mly

@@ -591,7 +591,7 @@ assignment:
     in {region; value}}
 
 rhs:
-  expr  { Expr $1 }
+  expr  { $1 }
 
 lhs:
   path       {    Path $1 }

src/passes/1-parser/pascaligo/ParserLog.ml

@@ -309,9 +309,7 @@ and print_assignment {value; _} =
   print_token assign ":=";
   print_rhs rhs
 
-and print_rhs = function
-      Expr e -> print_expr e
-| NoneExpr r -> print_token r "None"
+and print_rhs e = print_expr e
 
 and print_lhs = function
   Path path -> print_path path

src/passes/2-simplify/pascaligo.ml

@@ -26,16 +26,6 @@ module Errors = struct
     ] in
     error ~data title message
 
-  let unsupported_ass_None region =
-    let title () = "assignment of None" in
-    let message () =
-      Format.asprintf "assignments of None are not supported yet" in
-    let data = [
-      ("none_expr",
-       fun () -> Format.asprintf "%a" Location.pp_lift @@ region)
-    ] in
-    error ~data title message
-
   let bad_bytes loc str =
     let title () = "bad bytes string" in
     let message () =
@@ -793,10 +783,7 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
     )
   | Assign a -> (
       let (a , loc) = r_split a in
-      let%bind value_expr = match a.rhs with
-        | Expr e -> simpl_expression e
-        | NoneExpr reg -> fail @@ unsupported_ass_None reg
-      in
+      let%bind value_expr = simpl_expression a.rhs in
       match a.lhs with
         | Path path -> (
             let (name , path') = simpl_path path in

src/passes/4-typer/typer.ml

@@ -726,7 +726,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
           fail @@ not_supported_yet "assign expressions with maps are not supported yet" ae
       in
       bind_fold_list aux (typed_name.type_value , []) path in
-    let%bind expr' = type_expression e expr in
+    let%bind expr' = type_expression e ~tv_opt:assign_tv expr in
     let t_expr' = get_type_annotation expr' in
     let%bind () =
       trace_strong (type_error

src/test/contracts/option.ligo

@@ -4,3 +4,12 @@ type foobar is option(int)
 
 const s : foobar = Some(42)
 const n : foobar = None
+
+function assign (var m : int) : foobar is
+  var coco : foobar := None;
+  block
+{
+      coco := Some(m);
+      coco := None;
+}
+with coco

src/test/integration_tests.ml

@@ -369,6 +369,10 @@ let option () : unit result =
     let expected = e_typed_none t_int in
     expect_eq_evaluate program "n" expected
   in
+  let%bind () =
+    let expected = e_typed_none t_int in
+    expect_eq program "assign" (e_int 12) expected
+  in
   ok ()
 
 let moption () : unit result =