From f9b6718308921de62c7fcb7f22b2cd618cffb899 Mon Sep 17 00:00:00 2001
From: Vastargazing <vebohr@gmail.com>
Date: Sat, 11 Apr 2026 08:25:49 +0300
Subject: [PATCH] add regression test for OpenOptionsExt downstream compat

---
 tests/ui/std/open-options-ext-compat.rs | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 tests/ui/std/open-options-ext-compat.rs

diff --git a/tests/ui/std/open-options-ext-compat.rs b/tests/ui/std/open-options-ext-compat.rs
new file mode 100644
index 0000000000000..783b1e0961cbb
--- /dev/null
+++ b/tests/ui/std/open-options-ext-compat.rs
@@ -0,0 +1,20 @@
+//@ only-windows
+//@ check-pass
+
+// Regression test for https://github.com/rust-lang/rust/issues/153486
+// Ensures that `OpenOptionsExt` remains implementable by downstream crates
+// without requiring changes when new methods are added to the standard library.
+
+use std::os::windows::fs::OpenOptionsExt;
+
+struct MockOptions;
+
+impl OpenOptionsExt for MockOptions {
+    fn access_mode(&mut self, _: u32) -> &mut Self { self }
+    fn share_mode(&mut self, _: u32) -> &mut Self { self }
+    fn custom_flags(&mut self, _: u32) -> &mut Self { self }
+    fn attributes(&mut self, _: u32) -> &mut Self { self }
+    fn security_qos_flags(&mut self, _: u32) -> &mut Self { self }
+}
+
+fn main() {}