Add more niche-optimization tests.

This ports in the new tests added in rust-lang/rust#96947.

examples/hello.rs

@@ -16,7 +16,7 @@ use std::{
 use io_lifetimes::{AsFd, FromFd, OwnedFd};
 
 #[cfg(windows)]
-use io_lifetimes::{AsHandle, FromHandle, InvalidHandleError, OwnedHandle};
+use io_lifetimes::{AsHandle, FromHandle, OwnedHandle};
 #[cfg(windows)]
 use std::{convert::TryInto, os::windows::io::RawHandle, ptr::null_mut};
 

tests/niche-optimizations.rs

@@ -10,17 +10,33 @@ use io_lifetimes::{BorrowedFd, OwnedFd};
 use io_lifetimes::{BorrowedSocket, OwnedSocket};
 
 #[cfg(unix)]
-use std::os::unix::io::RawFd;
+use std::os::unix::io::{FromRawFd, IntoRawFd, RawFd};
 #[cfg(target_os = "wasi")]
-use std::os::wasi::io::RawFd;
+use std::os::wasi::io::{FromRawSocket, IntoRawSocket, RawFd};
 #[cfg(windows)]
-use std::os::windows::io::RawSocket;
+use std::os::windows::io::{FromRawSocket, IntoRawSocket, RawSocket};
 
 #[cfg(all(rustc_attrs, any(unix, target_os = "wasi")))]
 #[test]
 fn test_niche_optimizations() {
     assert_eq!(size_of::<Option<OwnedFd>>(), size_of::<RawFd>());
     assert_eq!(size_of::<Option<BorrowedFd<'static>>>(), size_of::<RawFd>());
+    unsafe {
+        assert_eq!(OwnedFd::from_raw_fd(RawFd::MIN).into_raw_fd(), RawFd::MIN);
+        assert_eq!(OwnedFd::from_raw_fd(RawFd::MAX).into_raw_fd(), RawFd::MAX);
+        assert_eq!(
+            Some(OwnedFd::from_raw_fd(RawFd::MIN))
+                .unwrap()
+                .into_raw_fd(),
+            RawFd::MIN
+        );
+        assert_eq!(
+            Some(OwnedFd::from_raw_fd(RawFd::MAX))
+                .unwrap()
+                .into_raw_fd(),
+            RawFd::MAX
+        );
+    }
 }
 
 #[cfg(all(rustc_attrs, windows))]
@@ -31,4 +47,25 @@ fn test_niche_optimizations_socket() {
         size_of::<Option<BorrowedSocket<'static>>>(),
         size_of::<RawSocket>(),
     );
+    unsafe {
+        #[cfg(target_pointer_width = "32")]
+        let (min, max) = (i32::MIN as u32, i32::MAX as u32);
+        #[cfg(target_pointer_width = "64")]
+        let (min, max) = (i64::MIN as u64, i64::MAX as u64);
+
+        assert_eq!(OwnedSocket::from_raw_socket(min).into_raw_socket(), min);
+        assert_eq!(OwnedSocket::from_raw_socket(max).into_raw_socket(), max);
+        assert_eq!(
+            Some(OwnedSocket::from_raw_socket(min))
+                .unwrap()
+                .into_raw_socket(),
+            min
+        );
+        assert_eq!(
+            Some(OwnedSocket::from_raw_socket(max))
+                .unwrap()
+                .into_raw_socket(),
+            max
+        );
+    }
 }