Sep 9, 2025 · Sep 9, 2025 · Sep 9, 2025
diff --git a/compiler/syntax/src/res_core.ml b/compiler/syntax/src/res_core.ml
 and parse_jsx_props p : Parsetree.jsx_prop list =
  parse_region ~grammar:Grammar.JsxAttribute ~f:parse_jsx_prop p

 and wrap_jsx_string_literal expr =
  (* Check if the expression is a string literal and wrap it with Jsx.string() *)
  match expr.Parsetree.pexp_desc with
  | Pexp_constant (Pconst_string (s, delimiter)) ->
    let jsx_string_ident =
      Ast_helper.Exp.ident
        ~loc:expr.pexp_loc
        (Location.mkloc (Longident.Ldot (Longident.Lident "Jsx", "string")) expr.pexp_loc)
    in
    Ast_helper.Exp.apply
      ~loc:expr.pexp_loc
      jsx_string_ident
      [(Nolabel, expr)]
  | _ -> expr

 and parse_jsx_children p : Parsetree.jsx_children =
  let rec loop p children =
    match p.Parser.token with
      let child =
        parse_primary_expr ~operand:(parse_atomic_expr p) ~no_call:true p
      in
      loop p (child :: children)
      let wrapped_child = wrap_jsx_string_literal child in
      loop p (wrapped_child :: children)
    | token when Grammar.is_jsx_child_start token ->
      let child =
        parse_primary_expr ~operand:(parse_atomic_expr p) ~no_call:true p
      in
      loop p (child :: children)
      let wrapped_child = wrap_jsx_string_literal child in
      loop p (wrapped_child :: children)
    | _ -> children
  in
  let children =
diff --git a/tests/syntax_tests/data/parsing/grammar/expressions/jsx.res b/tests/syntax_tests/data/parsing/grammar/expressions/jsx.res

 let _ = <div onClick=onClickHandler> <> "foobar" </> </div>

 // Test automatic string wrapping in JSX children
 let _ = <span>hello world</span>
 let _ = <div>simple string</div>
 let _ = <> fragment string </>
 let _ = <div>first string<span>nested</span>last string</div>


 let _ =
   <Window
Original file line number	Diff line number	Diff line change
Expand Up		@@ -2977,6 +2977,21 @@ and parse_jsx_prop p : Parsetree.jsx_prop option =
		and parse_jsx_props p : Parsetree.jsx_prop list =
		parse_region ~grammar:Grammar.JsxAttribute ~f:parse_jsx_prop p

		and wrap_jsx_string_literal expr =
		(* Check if the expression is a string literal and wrap it with Jsx.string() *)
		match expr.Parsetree.pexp_desc with
		\| Pexp_constant (Pconst_string (s, delimiter)) ->
		let jsx_string_ident =
		Ast_helper.Exp.ident
		~loc:expr.pexp_loc
		(Location.mkloc (Longident.Ldot (Longident.Lident "Jsx", "string")) expr.pexp_loc)
		in
		Ast_helper.Exp.apply
		~loc:expr.pexp_loc
		jsx_string_ident
		[(Nolabel, expr)]
		\| _ -> expr

		and parse_jsx_children p : Parsetree.jsx_children =
		let rec loop p children =
		match p.Parser.token with
Expand All		@@ -2991,12 +3006,14 @@ and parse_jsx_children p : Parsetree.jsx_children =
		let child =
		parse_primary_expr ~operand:(parse_atomic_expr p) ~no_call:true p
		in
		loop p (child :: children)
		let wrapped_child = wrap_jsx_string_literal child in
		loop p (wrapped_child :: children)
		\| token when Grammar.is_jsx_child_start token ->
		let child =
		parse_primary_expr ~operand:(parse_atomic_expr p) ~no_call:true p
		in
		loop p (child :: children)
		let wrapped_child = wrap_jsx_string_literal child in
		loop p (wrapped_child :: children)
		\| _ -> children
		in
		let children =
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -86,6 +86,12 @@ let _ = <Outer inner=<Inner /> />

		let _ = <div onClick=onClickHandler> <> "foobar" </> </div>

		// Test automatic string wrapping in JSX children
		let _ = <span>hello world</span>
		let _ = <div>simple string</div>
		let _ = <> fragment string </>
		let _ = <div>first string<span>nested</span>last string</div>


		let _ =
		<Window
Expand Down