Assertion of parseJsImport fails

src/res_core.ml

@@ -5408,11 +5408,15 @@ and parseJsImport ~startPos ~attrs p =
   let importSpec =
     match p.Parser.token with
     | Token.Lident _ | Token.At ->
+      Parser.leaveBreadcrumb p Grammar.JsFfiImport;
       let decl =
         match parseJsFfiDeclaration p with
         | Some decl -> decl
-        | None -> assert false
+        | None ->
+          Parser.err p (Diagnostics.unexpected p.Parser.token p.breadcrumbs);
+          JsFfi.emptyDecl p.startPos
       in
+      Parser.eatBreadcrumb p;
       JsFfi.Default decl
     | _ -> JsFfi.Spec (parseJsFfiDeclarations p)
   in

src/res_js_ffi.ml

@@ -32,6 +32,19 @@ let decl ~attrs ~loc ~name ~alias ~typ =
     jld_type = typ;
   }
 
+let emptyDecl loc =
+  let loc = Location.{loc_start = loc; loc_end = loc; loc_ghost = false} in
+  let emptyCoreType : Parsetree.core_type =
+    {ptyp_desc = Parsetree.Ptyp_any; ptyp_loc = loc; ptyp_attributes = []}
+  in
+  {
+    jld_loc = loc;
+    jld_attributes = [];
+    jld_name = "";
+    jld_alias = "";
+    jld_type = emptyCoreType;
+  }
+
 let importDescr ~attrs ~scope ~importSpec ~loc =
   {
     jid_loc = loc;

tests/parsing/errors/other/expected/import.res.txt

@@ -0,0 +1,10 @@
+
+  Syntax error!
+  tests/parsing/errors/other/import.res:2:1
+
+  1 │ import@
+  2 │ 
+
+  I'm not sure what to parse here when looking at "eof".
+
+include struct external Fatal error: exception Invalid_argument("index out of bounds")

tests/parsing/errors/other/import.res

@@ -0,0 +1 @@
+import@