Mark async/await as experimental.

rescript-lang · Sep 9, 2022 · 6e106e9 · 6e106e9
1 parent 68a3f5c
commit 6e106e9
Show file tree

Hide file tree

Showing 4 changed files with 100 additions and 82 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -18,7 +18,7 @@
 
 #### :rocket: New Feature
 
-- Add support for for `async`/`await` https://github.com/rescript-lang/rescript-compiler/pull/5537
+- Experimental support for for `async`/`await` https://github.com/rescript-lang/rescript-compiler/pull/5537
 
 - Make `promise` a built-in type https://github.com/rescript-lang/rescript-compiler/pull/5650
 

diff --git a/lib/4.06.1/unstable/js_compiler.ml b/lib/4.06.1/unstable/js_compiler.ml
@@ -40818,33 +40818,39 @@ and type_expect ?in_function ?recarg env sexp ty_expected =
   (Cmt_format.Partial_expression exp :: previous_saved_types);
   exp
 
-and checkTypeInvariant exp = 
-let rec extractPromise t =
-  match t.desc with
-  | Tconstr (Pdot (Pdot (Pident {name = "Js"}, "Promise", _), "t", _), [t1], _)
-  | Tconstr (Pident {name = "promise"}, [t1], _)
-    ->
-    Some t1
-  | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> extractPromise t1
-  | _ -> None
-in
-let rec findNestedPromise t =
-  match t.desc with
-  | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> findNestedPromise t1
-  | Tconstr (_, ts, _) -> (
-    match extractPromise t with
-    | Some t1 -> (
-      match extractPromise t1 with
-      | Some _t2 ->
-        let nestedType = Format.asprintf "%a" Printtyp.type_expr t in
-        Location.prerr_warning exp.exp_loc (Bs_nested_promise nestedType)
-      | None -> ts |> List.iter findNestedPromise)
-    | None -> ts |> List.iter findNestedPromise)
-  | Tarrow (_, t1, t2, _) ->
-    findNestedPromise t1;
-    findNestedPromise t2
-  | _ -> ()
- in findNestedPromise exp.exp_type
+(* NOTE: the type invariant check should have no side effects and be efficient *)
+and checkTypeInvariant exp : unit =
+  let rec extractPromise t =
+    match t.desc with
+    | Tconstr
+        (Pdot (Pdot (Pident { name = "Js" }, "Promise", _), "t", _), [ t1 ], _)
+    | Tconstr (Pident { name = "promise" }, [ t1 ], _) ->
+      (* Improvement: check for type aliases, if it can be done efficiently *)
+        Some t1
+    | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> extractPromise t1
+    | _ -> None
+  in
+  (* Only traverse arguments of a type constructors and function types.
+     This should guarantee that the traversal finished quickly. *)
+  let rec findNestedPromise t =
+    match t.desc with
+    | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> findNestedPromise t1
+    | Tconstr (_, ts, _) -> (
+        match extractPromise t with
+        | Some t1 -> (
+            match extractPromise t1 with
+            | Some _t2 ->
+                let nestedType = Format.asprintf "%a" Printtyp.type_expr t in
+                Location.prerr_warning exp.exp_loc
+                  (Bs_nested_promise nestedType)
+            | None -> ts |> List.iter findNestedPromise)
+        | None -> ts |> List.iter findNestedPromise)
+    | Tarrow (_, t1, t2, _) ->
+        findNestedPromise t1;
+        findNestedPromise t2
+    | _ -> ()
+  in
+  findNestedPromise exp.exp_type
 
 and type_expect_ ?in_function ?(recarg=Rejected) env sexp ty_expected =
   let loc = sexp.pexp_loc in

diff --git a/lib/4.06.1/unstable/js_playground_compiler.ml b/lib/4.06.1/unstable/js_playground_compiler.ml
@@ -40818,33 +40818,39 @@ and type_expect ?in_function ?recarg env sexp ty_expected =
   (Cmt_format.Partial_expression exp :: previous_saved_types);
   exp
 
-and checkTypeInvariant exp = 
-let rec extractPromise t =
-  match t.desc with
-  | Tconstr (Pdot (Pdot (Pident {name = "Js"}, "Promise", _), "t", _), [t1], _)
-  | Tconstr (Pident {name = "promise"}, [t1], _)
-    ->
-    Some t1
-  | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> extractPromise t1
-  | _ -> None
-in
-let rec findNestedPromise t =
-  match t.desc with
-  | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> findNestedPromise t1
-  | Tconstr (_, ts, _) -> (
-    match extractPromise t with
-    | Some t1 -> (
-      match extractPromise t1 with
-      | Some _t2 ->
-        let nestedType = Format.asprintf "%a" Printtyp.type_expr t in
-        Location.prerr_warning exp.exp_loc (Bs_nested_promise nestedType)
-      | None -> ts |> List.iter findNestedPromise)
-    | None -> ts |> List.iter findNestedPromise)
-  | Tarrow (_, t1, t2, _) ->
-    findNestedPromise t1;
-    findNestedPromise t2
-  | _ -> ()
- in findNestedPromise exp.exp_type
+(* NOTE: the type invariant check should have no side effects and be efficient *)
+and checkTypeInvariant exp : unit =
+  let rec extractPromise t =
+    match t.desc with
+    | Tconstr
+        (Pdot (Pdot (Pident { name = "Js" }, "Promise", _), "t", _), [ t1 ], _)
+    | Tconstr (Pident { name = "promise" }, [ t1 ], _) ->
+      (* Improvement: check for type aliases, if it can be done efficiently *)
+        Some t1
+    | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> extractPromise t1
+    | _ -> None
+  in
+  (* Only traverse arguments of a type constructors and function types.
+     This should guarantee that the traversal finished quickly. *)
+  let rec findNestedPromise t =
+    match t.desc with
+    | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> findNestedPromise t1
+    | Tconstr (_, ts, _) -> (
+        match extractPromise t with
+        | Some t1 -> (
+            match extractPromise t1 with
+            | Some _t2 ->
+                let nestedType = Format.asprintf "%a" Printtyp.type_expr t in
+                Location.prerr_warning exp.exp_loc
+                  (Bs_nested_promise nestedType)
+            | None -> ts |> List.iter findNestedPromise)
+        | None -> ts |> List.iter findNestedPromise)
+    | Tarrow (_, t1, t2, _) ->
+        findNestedPromise t1;
+        findNestedPromise t2
+    | _ -> ()
+  in
+  findNestedPromise exp.exp_type
 
 and type_expect_ ?in_function ?(recarg=Rejected) env sexp ty_expected =
   let loc = sexp.pexp_loc in

diff --git a/lib/4.06.1/whole_compiler.ml b/lib/4.06.1/whole_compiler.ml
@@ -217205,33 +217205,39 @@ and type_expect ?in_function ?recarg env sexp ty_expected =
   (Cmt_format.Partial_expression exp :: previous_saved_types);
   exp
 
-and checkTypeInvariant exp = 
-let rec extractPromise t =
-  match t.desc with
-  | Tconstr (Pdot (Pdot (Pident {name = "Js"}, "Promise", _), "t", _), [t1], _)
-  | Tconstr (Pident {name = "promise"}, [t1], _)
-    ->
-    Some t1
-  | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> extractPromise t1
-  | _ -> None
-in
-let rec findNestedPromise t =
-  match t.desc with
-  | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> findNestedPromise t1
-  | Tconstr (_, ts, _) -> (
-    match extractPromise t with
-    | Some t1 -> (
-      match extractPromise t1 with
-      | Some _t2 ->
-        let nestedType = Format.asprintf "%a" Printtyp.type_expr t in
-        Location.prerr_warning exp.exp_loc (Bs_nested_promise nestedType)
-      | None -> ts |> List.iter findNestedPromise)
-    | None -> ts |> List.iter findNestedPromise)
-  | Tarrow (_, t1, t2, _) ->
-    findNestedPromise t1;
-    findNestedPromise t2
-  | _ -> ()
- in findNestedPromise exp.exp_type
+(* NOTE: the type invariant check should have no side effects and be efficient *)
+and checkTypeInvariant exp : unit =
+  let rec extractPromise t =
+    match t.desc with
+    | Tconstr
+        (Pdot (Pdot (Pident { name = "Js" }, "Promise", _), "t", _), [ t1 ], _)
+    | Tconstr (Pident { name = "promise" }, [ t1 ], _) ->
+      (* Improvement: check for type aliases, if it can be done efficiently *)
+        Some t1
+    | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> extractPromise t1
+    | _ -> None
+  in
+  (* Only traverse arguments of a type constructors and function types.
+     This should guarantee that the traversal finished quickly. *)
+  let rec findNestedPromise t =
+    match t.desc with
+    | Tlink t1 | Tsubst t1 | Tpoly (t1, []) -> findNestedPromise t1
+    | Tconstr (_, ts, _) -> (
+        match extractPromise t with
+        | Some t1 -> (
+            match extractPromise t1 with
+            | Some _t2 ->
+                let nestedType = Format.asprintf "%a" Printtyp.type_expr t in
+                Location.prerr_warning exp.exp_loc
+                  (Bs_nested_promise nestedType)
+            | None -> ts |> List.iter findNestedPromise)
+        | None -> ts |> List.iter findNestedPromise)
+    | Tarrow (_, t1, t2, _) ->
+        findNestedPromise t1;
+        findNestedPromise t2
+    | _ -> ()
+  in
+  findNestedPromise exp.exp_type
 
 and type_expect_ ?in_function ?(recarg=Rejected) env sexp ty_expected =
   let loc = sexp.pexp_loc in