@notundefined attribute for abstract types

Author: cknitt

compiler/ml/typeopt.ml

@@ -50,17 +50,14 @@ let rec type_cannot_contain_undefined (typ : Types.type_expr) (env : Env.t) =
     | For_sure_yes -> true
     | For_sure_no -> false
     | NA -> (
-      let untagged = ref false in
-      match
-        let decl = Env.find_type p env in
-        let () =
-          if Ast_untagged_variants.has_untagged decl.type_attributes then
-            untagged := true
-        in
-        decl.type_kind
-      with
+      let decl = Env.find_type p env in
+      match decl.type_kind with
       | exception _ -> false
-      | Type_abstract | Type_open -> false
+      | Type_abstract ->
+        List.exists
+          (fun ({txt}, _) -> txt = "notUndefined")
+          decl.type_attributes
+      | Type_open -> false
       | Type_record _ -> true
       | Type_variant
           ( [
@@ -74,10 +71,13 @@ let rec type_cannot_contain_undefined (typ : Types.type_expr) (env : Env.t) =
           | [{cd_id = {name = "()"}; cd_args = Cstr_tuple []}] ) ->
         false (* conservative *)
       | Type_variant cdecls ->
+        let untagged =
+          Ast_untagged_variants.has_untagged decl.type_attributes
+        in
         Ext_list.for_all cdecls (fun cd ->
             if Ast_untagged_variants.has_undefined_literal cd.cd_attributes then
               false
-            else if !untagged then
+            else if untagged then
               match cd.cd_args with
               | Cstr_tuple [t] ->
                 Ast_untagged_variants.type_is_builtin_object t

runtime/Jsx.res

@@ -24,7 +24,8 @@
 
 // Define this as a private empty record so that the compiler does not
 // unnecessarily add `Primitive_option.some` calls for optional props.
-type element = private {}
+@notUndefined
+type element
 
 @val external null: element = "null"
 

runtime/Stdlib_Date.res

@@ -1,3 +1,4 @@
+@notUndefined
 type t
 
 type msSinceEpoch = float

runtime/Stdlib_Date.resi

@@ -5,6 +5,7 @@
 /**
 A type representing a JavaScript date.
 */
+@notUndefined
 type t
 
 /**

runtime/Stdlib_RegExp.res

@@ -1,3 +1,4 @@
+@notUndefined
 type t
 
 module Result = {

runtime/Stdlib_RegExp.resi

@@ -7,6 +7,7 @@ See [`RegExp`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference
 /**
 Type representing an instantiated `RegExp`.
 */
+@notUndefined
 type t
 
 module Result: {

tests/analysis_tests/tests/src/expected/Completion.res.txt

@@ -0,0 +1,44 @@
+// Generated by ReScript, PLEASE EDIT WITH CARE
+
+import * as Primitive_option from "rescript/lib/es6/Primitive_option.js";
+
+let x4 = [
+  1,
+  2,
+  3
+];
+
+let x5 = () => {};
+
+let x10 = null;
+
+let x11 = Primitive_option.some(undefined);
+
+let x20 = null;
+
+let x21 = new Date();
+
+let x22 = /test/;
+
+let x1 = "hello";
+
+let x2 = 1;
+
+let x3 = "polyvar";
+
+let x12 = "test";
+
+export {
+  x1,
+  x2,
+  x3,
+  x4,
+  x5,
+  x10,
+  x11,
+  x12,
+  x20,
+  x21,
+  x22,
+}
+/* x20 Not a pure module */

tests/tests/src/option_wrapping_test.mjs

@@ -0,0 +1,13 @@
+let x1 = Some("hello")
+let x2 = Some(1)
+let x3 = Some(#polyvar)
+let x4 = Some([1, 2, 3])
+let x5 = Some(() => ())
+
+let x10 = Some(Nullable.null)
+let x11 = Some(Nullable.undefined)
+let x12 = Some(Nullable.Value("test"))
+
+let x20 = Some(Jsx.null)
+let x21 = Some(Date.make())
+let x22 = Some(/test/)