Leave the error marker out of own property names (#1476)

packages/compiler/test/ts7/baselines/order-parity/tests/corpus/6401-dyn-error-own-property-names.ts.json

@@ -0,0 +1,6 @@
+{
+ "order": [
+  "<repo>/tests/corpus/6401-dyn-error-own-property-names.ts"
+ ],
+ "diags": []
+}

packages/compiler/test/ts7/baselines/order-parity/tests/corpus/6402-dyn-error-own-property-names-js.js.json

@@ -0,0 +1,6 @@
+{
+ "order": [
+  "<repo>/tests/corpus/6402-dyn-error-own-property-names-js.js"
+ ],
+ "diags": []
+}

packages/runtime/src/scr_json.c

@@ -11478,7 +11478,20 @@ ScrDyn *scr_dyn_get_own_property_names(const ScrDyn *value) {
     scr_dyn_release(table);
     return out;
   }
-  if (value->kind == SCR_DYN_OBJ) return scr_dyn_obj_own_keys(value);
+  if (value->kind == SCR_DYN_OBJ) {
+    ScrDyn *keys = scr_dyn_obj_own_keys(value);
+    if (!scr_dyn_obj_get(value, "%error", 6)) return keys;
+    /* The checked-dynamic tree's error marker is not a property. */
+    ScrDyn *names = scr_dyn_new_arr();
+    scr_dyn_arr_reserve(names, keys->v.arr.len);
+    for (size_t i = 0; i < keys->v.arr.len; i++) {
+      const ScrStr *key = keys->v.arr.items[i]->v.str;
+      if (key->len == 6 && memcmp(key->data, "%error", 6) == 0) continue;
+      scr_dyn_arr_push(names, scr_dyn_retain(keys->v.arr.items[i]));
+    }
+    scr_dyn_release(keys);
+    return names;
+  }
   if (value->kind == SCR_DYN_ARR || value->kind == SCR_DYN_STR || value->kind == SCR_DYN_BYTES) {
     ScrDyn *keys = scr_dyn_new_arr();
     size_t length = value->kind == SCR_DYN_ARR ? value->v.arr.len :

tests/corpus/6401-dyn-error-own-property-names.ts

@@ -0,0 +1,44 @@
+// The own property names of errors held as `any` or `unknown` match
+// Node's: Object.getOwnPropertyNames, Reflect.ownKeys and
+// Object.getOwnPropertyDescriptors list `stack`, `message` and the
+// properties the error has, in order, and nothing else.
+
+class PlainSubclass extends Error {}
+
+function dyn(value: unknown): any {
+  return value;
+}
+
+function names(label: string, error: any): void {
+  console.log(
+    label,
+    "|",
+    Object.getOwnPropertyNames(error).join(","),
+    "|",
+    Reflect.ownKeys(error).map(String).join(","),
+    "|",
+    Object.keys(Object.getOwnPropertyDescriptors(error)).join(","),
+  );
+}
+
+names("error", dyn(new Error("plain")));
+names("type error", dyn(new TypeError("bad thing")));
+names("no message", dyn(new RangeError()));
+names("cause", dyn(new Error("outer", { cause: new Error("inner") })));
+names("subclass", dyn(new PlainSubclass("sub")));
+
+const unknownError: unknown = new SyntaxError("unexpected");
+names("unknown", unknownError);
+
+const coded = dyn(new Error("with code"));
+coded.code = "E_CODE";
+coded.detail = 1;
+names("own properties", coded);
+
+try {
+  throw new URIError("thrown");
+} catch (error) {
+  names("caught", error);
+}
+
+console.log("marker", Object.getOwnPropertyNames(dyn(new Error("x"))).some((name) => name.startsWith("%")));

tests/corpus/6402-dyn-error-own-property-names-js.js

@@ -0,0 +1,44 @@
+// In JavaScript sources, the own property names of errors match
+// Node's: Object.getOwnPropertyNames, Reflect.ownKeys and
+// Object.getOwnPropertyDescriptors list `stack`, `message` and the
+// properties the error has, in order, and nothing else.
+
+class PlainSubclass extends Error {}
+
+function dyn(value) {
+  return value;
+}
+
+function names(label, error) {
+  console.log(
+    label,
+    "|",
+    Object.getOwnPropertyNames(error).join(","),
+    "|",
+    Reflect.ownKeys(error).map(String).join(","),
+    "|",
+    Object.keys(Object.getOwnPropertyDescriptors(error)).join(","),
+  );
+}
+
+names("error", dyn(new Error("plain")));
+names("type error", dyn(new TypeError("bad thing")));
+names("no message", dyn(new RangeError()));
+names("cause", dyn(new Error("outer", { cause: new Error("inner") })));
+names("subclass", dyn(new PlainSubclass("sub")));
+
+const unknownError = new SyntaxError("unexpected");
+names("unknown", unknownError);
+
+const coded = dyn(new Error("with code"));
+coded.code = "E_CODE";
+coded.detail = 1;
+names("own properties", coded);
+
+try {
+  throw new URIError("thrown");
+} catch (error) {
+  names("caught", error);
+}
+
+console.log("marker", Object.getOwnPropertyNames(dyn(new Error("x"))).some((name) => name.startsWith("%")));

tests/harness/corpus-costs/6401-dyn-error-own-property-names.ts.json

@@ -0,0 +1 @@
+{ "plain": 3175, "san": 4362 }

tests/harness/corpus-costs/6402-dyn-error-own-property-names-js.js.json

@@ -0,0 +1 @@
+{ "plain": 3056, "san": 4620 }