Bug test: Function.prototype.name writability

api-testcases/test-bug-set-cfunc-name.c

@@ -0,0 +1,55 @@
+/*
+ *  Duktape 1.0 issue: cannot set Duktape/C function 'name' property after
+ *  creation.
+ *
+ *  The cause: Function.prototype.name, containing an empty string, is
+ *  non-writable.  This is an unintended side effect of all built-in
+ *  functions (such as Array, Math.cos, etc) having a non-writable name.
+ *  Function.prototype, although never really called, is technically a
+ *  function so its empty name is unintentionally non-writable.
+ *
+ *  Fixed in Duktape 1.1 so that Function.prototype.name is writable.
+ *  The best fix would actually be to have the property non-writable
+ *  while simultaneously allowing a Function instance's 'name' property
+ *  to be set - but Ecmascript cannot express such an access control
+ *  policy.
+ */
+
+/*===
+*** test_1 (duk_safe_call)
+writable: true
+enumerable: false
+configurable: false
+MyFunc.name: my_func_name
+final top: 0
+==> rc=0, result='undefined'
+===*/
+
+static duk_ret_t my_func(duk_context *ctx) {
+	(void) ctx;
+	return 0;
+}
+
+static duk_ret_t test_1(duk_context *ctx) {
+	/* Check that Function.prototype.name is writable. */
+	duk_eval_string_noresult(ctx,
+		"var pd = Object.getOwnPropertyDescriptor(Function.prototype, 'name');\n"
+		"print('writable:', pd.writable);\n"
+		"print('enumerable:', pd.enumerable);\n"
+		"print('configurable:', pd.configurable);\n");
+
+	duk_push_c_function(ctx, my_func, 0);
+	duk_push_string(ctx, "my_func_name");
+	duk_put_prop_string(ctx, -2, "name");
+	duk_put_global_string(ctx, "MyFunc");
+
+	duk_eval_string_noresult(ctx,
+		"print('MyFunc.name:', MyFunc.name);\n");
+
+	printf("final top: %ld\n", (long) duk_get_top(ctx));
+	return 0;
+}
+
+void test(duk_context *ctx) {
+	TEST_SAFE_CALL(test_1);
+}