micropython · dpgeorge · Jul 4, 2025 · Jul 2, 2025
diff --git a/ports/webassembly/objpyproxy.js b/ports/webassembly/objpyproxy.js
@@ -148,6 +148,12 @@ const py_proxy_handler = {
         };
     },
     has(target, prop) {
+        // avoid throwing on `Symbol() in proxy` checks
+        if (typeof prop !== "string") {
+            // returns true only on iterator because other
+            // symbols are not considered in the `get` trap
+            return prop === Symbol.iterator;
+        }
         return Module.ccall(
             "proxy_c_to_js_has_attr",
             "number",

diff --git a/tests/ports/webassembly/py_proxy_has.mjs b/tests/ports/webassembly/py_proxy_has.mjs
@@ -9,3 +9,5 @@ x = []
 const x = mp.globals.get("x");
 console.log("no_exist" in x);
 console.log("sort" in x);
+console.log(Symbol.toStringTag in x);
+console.log(Symbol.iterator in x);
diff --git a/tests/ports/webassembly/py_proxy_has.mjs.exp b/tests/ports/webassembly/py_proxy_has.mjs.exp
@@ -1,2 +1,4 @@
 false
 true
+false
+true
-Original file line number
+Diff line change
@@ -1,2 +1,4 @@
     false
     true
+    false
+    true