From c56444556d8ad5a983a63826355da7eca8b9013d Mon Sep 17 00:00:00 2001
From: John Alanbrook <john@pockle.world>
Date: Wed, 25 Feb 2026 23:30:32 -0600
Subject: [PATCH] fix log in engine err

---
 source/cell.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/source/cell.c b/source/cell.c
index fb51b9f4..59f84152 100644
--- a/source/cell.c
+++ b/source/cell.c
@@ -313,6 +313,26 @@ void actor_disrupt(JSContext *ctx)
 JSValue js_core_internal_os_use(JSContext *js);
 JSValue js_core_json_use(JSContext *js);
 
+/* Engine-env log proxy: routes log("channel", [msg]) through JS_Log.
+   Before set_log is called, JS_Log falls back to stderr.
+   After set_log, JS_Log forwards to the engine's JS log function.
+   This exists so mcode-generated type-check error paths (which always
+   access 'log' as an intrinsic) work inside engine.cm itself. */
+static JSValue js_engine_log(JSContext *js, JSValue self,
+                             int argc, JSValue *argv) {
+  if (argc < 2) return JS_NULL;
+  const char *channel = JS_ToCString(js, argv[0]);
+  if (!channel) return JS_NULL;
+  JSValue msg_val = JS_GetPropertyNumber(js, argv[1], 0);
+  const char *msg = JS_ToCString(js, msg_val);
+  if (msg) {
+    JS_Log(js, channel, "%s", msg);
+    JS_FreeCString(js, msg);
+  }
+  JS_FreeCString(js, channel);
+  return JS_NULL;
+}
+
 void script_startup(JSContext *js)
 {
   if (!g_runtime) {
@@ -414,6 +434,8 @@ void script_startup(JSContext *js)
   }
   tmp = shop_path ? JS_NewString(js, shop_path) : JS_NULL;
   JS_SetPropertyStr(js, env_ref.val, "shop_path", tmp);
+  tmp = JS_NewCFunction(js, js_engine_log, "log", 2);
+  JS_SetPropertyStr(js, env_ref.val, "log", tmp);
 
   // Stone the environment
   JSValue hidden_env = JS_Stone(js, env_ref.val);
@@ -761,6 +783,8 @@ int cell_init(int argc, char **argv)
     }
     JS_SetPropertyStr(ctx, env_ref.val, "args", args_ref.val);
     JS_DeleteGCRef(ctx, &args_ref);
+    tmp = JS_NewCFunction(ctx, js_engine_log, "log", 2);
+    JS_SetPropertyStr(ctx, env_ref.val, "log", tmp);
     JSValue hidden_env = JS_Stone(ctx, env_ref.val);
 
     g_crash_ctx = ctx;