Wire adapter-html.sx into OCaml server, replacing hand-written renderer

sx_server.ml: sx_render_to_html() calls the SX adapter-html.sx render-to-html
via CEK eval, falling back to Sx_render.render_to_html if adapter not loaded.
CLI --render mode now loads render.sx + adapter-html.sx.

sx_primitives.ml: Added ~25 primitives needed by adapter-html.sx:
  scope-push!/pop!/peek/emit!, emitted, provide-push!/pop! (hashtable stack),
  lambda?/island?/component?/macro?, component-closure/name/params/body/
  has-children?, lambda-closure/params/body, is-else-clause?, for-each-indexed,
  empty-dict?, make-raw-html, raw-html-content

run_tests.ml: Loads render.sx + adapter-html.sx for test-render-html.sx.
Registers trampoline, eval-expr, scope stubs, expand-macro, cond-scheme?.

Status: 1105/1114 OCaml tests pass. 8 remaining failures are env-merge
edge cases in render-lambda-html/component-children/island rendering —
same adapter code works in JS (143/143).

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

hosts/ocaml/bin/run_tests.ml

@@ -269,6 +269,40 @@ let make_test_env () =
   (* --- HTML Renderer (from sx_render.ml library module) --- *)
   Sx.Sx_render.setup_render_env env;
 
+  (* 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);
+  bind "trampoline" (fun args ->
+    match args with
+    | [Thunk (expr, e)] -> eval_expr expr (Env e)
+    | [v] -> v
+    | _ -> Nil);
+  bind "eval-expr" (fun args ->
+    match args with
+    | [expr; Env e] -> eval_expr expr (Env e)
+    | [expr] -> eval_expr expr (Env env)
+    | _ -> raise (Eval_error "eval-expr: expected (expr env)"));
+  bind "scope-push!" (fun args ->
+    ignore (Sx_runtime.scope_push (List.hd args) (if List.length args > 1 then List.nth args 1 else Nil)); Nil);
+  bind "scope-pop!" (fun args ->
+    ignore (Sx_runtime.scope_pop (List.hd args)); Nil);
+  bind "cond-scheme?" (fun args ->
+    match args with
+    | [(List clauses | ListRef { contents = clauses })] ->
+      (match clauses with
+       | (List _ | ListRef _) :: _ -> Bool true
+       | _ -> Bool false)
+    | _ -> Bool false);
+  bind "expand-macro" (fun args ->
+    match args with
+    | [Macro m; (List a | ListRef { contents = a }); _] ->
+      let local = Sx_types.env_extend m.m_closure in
+      List.iteri (fun i p ->
+        ignore (Sx_types.env_bind local p (if i < List.length a then List.nth a i else Nil))
+      ) m.m_params;
+      eval_expr m.m_body (Env local)
+    | _ -> raise (Eval_error "expand-macro: expected (macro args env)"));
+
   (* --- Missing primitives referenced by tests --- *)
 
   bind "upcase" (fun args ->
@@ -637,16 +671,24 @@ let run_spec_tests env test_files =
   Printf.printf "\nLoading test framework...\n%!";
   load_and_eval framework_path;
 
-  (* Load compiler + VM spec for test-vm.sx *)
+  (* Load spec modules needed by tests *)
   let spec_dir = Filename.concat project_dir "spec" in
-  List.iter (fun name ->
-    let path = Filename.concat spec_dir name in
+  let web_dir = Filename.concat project_dir "web" in
+  let load_spec name dir =
+    let path = Filename.concat dir name in
     if Sys.file_exists path then begin
       Printf.printf "Loading %s...\n%!" name;
       (try load_and_eval path
        with e -> Printf.eprintf "Warning: %s: %s\n%!" name (Printexc.to_string e))
     end
-  ) ["bytecode.sx"; "compiler.sx"; "vm.sx"];
+  in
+  (* Render adapter for test-render-html.sx *)
+  load_spec "render.sx" spec_dir;
+  load_spec "adapter-html.sx" web_dir;
+  (* Compiler + VM for test-vm.sx *)
+  load_spec "bytecode.sx" spec_dir;
+  load_spec "compiler.sx" spec_dir;
+  load_spec "vm.sx" spec_dir;
 
   (* Determine test files *)
   let files = if test_files = [] then begin

hosts/ocaml/bin/sx_server.ml

@@ -898,6 +898,21 @@ let make_server_env () =
   env
 
 
+(* ====================================================================== *)
+(* SX render-to-html — calls adapter-html.sx via CEK                       *)
+(* ====================================================================== *)
+
+(** Render an SX expression to HTML using the SX adapter (adapter-html.sx).
+    Falls back to Sx_render.render_to_html if the SX adapter isn't loaded. *)
+let sx_render_to_html expr env =
+  if env_has env "render-to-html" then
+    let fn = env_get env "render-to-html" in
+    let result = Sx_ref.cek_call fn (List [expr; Env env]) in
+    match result with String s -> s | _ -> Sx_runtime.value_to_str result
+  else
+    Sx_render.render_to_html expr env
+
+
 (* ====================================================================== *)
 (* JIT hook registration                                                    *)
 (* ====================================================================== *)
@@ -1232,7 +1247,7 @@ let rec dispatch env cmd =
           let body_expr = match body_exprs with
             | [e] -> e | [] -> Nil | _ -> List (Symbol "<>" :: body_exprs)
           in
-          Sx_render.render_to_html body_expr env
+          sx_render_to_html body_expr env
         with e ->
           Printf.eprintf "[ssr] render-to-html failed: %s\n%!" (Printexc.to_string e);
           ""  (* fallback: client renders from SX source. Islands with
@@ -1253,7 +1268,7 @@ let rec dispatch env cmd =
                      :: Keyword "body-html" :: String body_html
                      :: resolved_kwargs in
       let shell_call = List (Symbol "~shared:shell/sx-page-shell" :: shell_args) in
-      let html = Sx_render.render_to_html shell_call env in
+      let html = sx_render_to_html shell_call env in
       let t3 = Unix.gettimeofday () in
       Printf.eprintf "[sx-page-full] aser=%.3fs io=%.3fs ssr=%.3fs shell=%.3fs total=%.3fs body=%d ssr=%d html=%d\n%!"
         (t1 -. t0) (t2 -. t1) (t2b -. t2) (t3 -. t2b) (t3 -. t0)
@@ -1279,7 +1294,7 @@ let rec dispatch env cmd =
         | [] -> Nil
         | _ -> List (Symbol "do" :: exprs)
       in
-      let html = Sx_render.render_to_html expr env in
+      let html = sx_render_to_html expr env in
       send_ok_string html
     with
     | Eval_error msg -> send_error msg
@@ -1406,9 +1421,11 @@ let cli_mode mode =
   let spec_files = [
     Filename.concat base "parser.sx";
     Filename.concat base "render.sx";
+    Filename.concat web_base "adapter-html.sx";
     Filename.concat web_base "adapter-sx.sx";
   ] in
-  (if mode = "aser" || mode = "aser-slot" then
+  (* Load spec files for all CLI modes that need rendering *)
+  (if mode = "aser" || mode = "aser-slot" || mode = "render" then
     cli_load_files env spec_files);
   (* Load any files passed via --load *)
   let load_files = ref [] in
@@ -1434,7 +1451,7 @@ let cli_mode mode =
       let exprs = Sx_parser.parse_all src in
       let expr = match exprs with
         | [e] -> e | [] -> Nil | _ -> List (Symbol "do" :: exprs) in
-      let html = Sx_render.render_to_html expr env in
+      let html = sx_render_to_html expr env in
       print_string html; flush stdout
     | "aser" ->
       let exprs = Sx_parser.parse_all src in