Copy attributes from original binding expression

compiler/syntax/src/jsx_v4.ml

@@ -1002,7 +1002,8 @@ let map_binding ~config ~empty_loc ~pstr_loc ~file_name ~rec_flag binding =
            Exp.fun_ ~arity:None nolabel None
              (Pat.var @@ Location.mknoloc "ref")
              inner_expression
-         else inner_expression)
+         else inner_expression (* Todo: filter out any attributes? *))
+        ~attrs:binding.pvb_expr.pexp_attributes
     in
     let full_expression =
       full_expression

tests/tests/src/alias_default_value_test.mjs

@@ -67,12 +67,28 @@ let C6 = {
   make: Alias_default_value_test$C6
 };
 
+function Alias_default_value_test$C7(props) {
+  'use memo';
+  let username = props.username;
+  let count = props.count;
+  let times = count !== 1 ? (
+      count !== 2 ? String(count) + " times" : "twice"
+    ) : "once";
+  let name = username !== undefined && username !== "" ? username : "Anonymous";
+  return "Hello " + name + ", you clicked me " + times;
+}
+
+let C7 = {
+  make: Alias_default_value_test$C7
+};
+
 export {
   C0,
   C1,
   C2,
   C3,
   C4,
   C6,
+  C7,
 }
 /* No side effect */

tests/tests/src/alias_default_value_test.res

@@ -43,3 +43,24 @@ module C6 = {
   @react.component
   let make = (~comp as module(Comp: Comp), ~x as (a, b)) => Comp.xx
 }
+
+module C7 = {
+  @react.component
+  let make =
+    @directive("'use memo'")
+    (~count, ~username=?) => {
+      let times = switch count {
+      | 1 => "once"
+      | 2 => "twice"
+      | n => Belt.Int.toString(n) ++ " times"
+      }
+
+      let name = switch username {
+      | Some("") => "Anonymous"
+      | Some(name) => name
+      | None => "Anonymous"
+      }
+
+      React.string(`Hello ${name}, you clicked me ` ++ times)
+    }
+}