Fix defhandler blockers: &key params, multi-body, HTML tags

Three fixes in run_tests.ml defhandler parser:
1. Extract &key param names, store in hdef["params"]. run-handler
   binds them from mock args before evaluating — fixes row-editing,
   tabs, inline-edit, profile-editing handlers.
2. Capture all body forms after params, wrap in (do ...) when
   multiple — fixes ex-slow (sleep before let).
3. Register all HTML tags as native fns via Sx_render.html_tags —
   fixes ex-bulk (tr tag), and enables aser to serialize any tag.

1352 → 1361 passing tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

hosts/ocaml/bin/run_tests.ml

@@ -281,6 +281,13 @@ let make_test_env () =
   (* --- HTML Renderer (from sx_render.ml library module) --- *)
   Sx_render.setup_render_env env;
 
+  (* HTML tag functions — bind all tags as native fns returning (tag ...args) *)
+  List.iter (fun tag ->
+    ignore (Sx_types.env_bind env tag
+      (NativeFn ("html:" ^ tag, fun args -> List (Symbol tag :: args))))
+  ) Sx_render.html_tags;
+  bind "is-html-tag?" (fun args -> match args with [String s] -> Bool (Sx_render.is_html_tag s) | _ -> Bool false);
+
   (* Stubs needed by adapter-html.sx when loaded at test time *)
   bind "set-render-active!" (fun _args -> Nil);
   bind "render-active?" (fun _args -> Bool true);
@@ -437,12 +444,26 @@ let make_test_env () =
         | rest -> (acc, rest) in
       let opts = Hashtbl.create 4 in
       let (_, remaining) = parse_opts opts rest in
-      let _params, body = match remaining with
-        | List p :: b :: _ -> (p, b) | List _p :: [] -> (_p, Nil) | _ -> ([], Nil) in
+      let params, body_forms = match remaining with
+        | List p :: rest -> (p, rest) | _ -> ([], []) in
+      (* Wrap multiple body forms in (do ...) *)
+      let body = match body_forms with
+        | [] -> Nil | [b] -> b
+        | forms -> List (Symbol "do" :: forms) in
+      (* Extract &key param names for binding *)
+      let key_params =
+        let rec collect acc in_key = function
+          | [] -> List.rev acc
+          | Symbol "&key" :: rest -> collect acc true rest
+          | Symbol "&rest" :: _ :: rest -> collect acc false rest
+          | Symbol s :: rest when in_key -> collect (s :: acc) true rest
+          | _ :: rest -> collect acc in_key rest
+        in collect [] false params in
       let hdef = Hashtbl.create 8 in
       Hashtbl.replace hdef "__type" (String "handler");
       Hashtbl.replace hdef "name" (String name);
       Hashtbl.replace hdef "body" body;
+      Hashtbl.replace hdef "params" (List (List.map (fun s -> String s) key_params));
       Hashtbl.replace hdef "closure" (Env eval_env);
       Hashtbl.replace hdef "method" (match Hashtbl.find_opt opts "method" with
         | Some (Keyword m) -> String m | Some v -> v | None -> String "get");

web/tests/test-handlers.sx

@@ -82,12 +82,24 @@
   run-handler
   (fn
     (hdef)
-    (let
-      ((result (aser (get hdef "body") (get hdef "closure"))))
-      (if
-        (sx-expr? result)
-        (sx-expr-source result)
-        (if (string? result) result (str result))))))
+    (do
+      (let
+        ((params (get hdef "params")) (closure (get hdef "closure")))
+        (when
+          (and params (not (empty? params)))
+          (for-each
+            (fn
+              (p)
+              (let
+                ((val (get _mock-args p)))
+                (env-bind! closure p (or val nil))))
+            params)))
+      (let
+        ((result (aser (get hdef "body") (get hdef "closure"))))
+        (if
+          (sx-expr? result)
+          (sx-expr-source result)
+          (if (string? result) result (str result)))))))
 
 (defsuite
   "example:click-to-load"

web/tests/test-swap-integration.sx

@@ -84,12 +84,24 @@
   run-handler
   (fn
     (hdef)
-    (let
-      ((result (aser (get hdef "body") (get hdef "closure"))))
-      (if
-        (sx-expr? result)
-        (sx-expr-source result)
-        (if (string? result) result (str result))))))
+    (do
+      (let
+        ((params (get hdef "params")) (closure (get hdef "closure")))
+        (when
+          (and params (not (empty? params)))
+          (for-each
+            (fn
+              (p)
+              (let
+                ((val (get _mock-args p)))
+                (env-bind! closure p (or val nil))))
+            params)))
+      (let
+        ((result (aser (get hdef "body") (get hdef "closure"))))
+        (if
+          (sx-expr? result)
+          (sx-expr-source result)
+          (if (string? result) result (str result)))))))
 
 (defsuite
   "swap:click-to-load"