test: restore more tests on cygwin

They pass on Cygwin, but not on MSYS2 as intended.

Author: Berrysoft

test/sys/test_stat.rs

@@ -145,7 +145,6 @@ fn test_stat_fstat_lstat() {
 }
 
 #[test]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_fchmod() {
     let tempdir = tempfile::tempdir().unwrap();
     let filename = tempdir.path().join("foo.txt");
@@ -169,7 +168,6 @@ fn test_fchmod() {
 
 #[test]
 #[cfg(not(target_os = "redox"))]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_fchmodat() {
     let _dr = crate::DirRestore::new();
     let tempdir = tempfile::tempdir().unwrap();
@@ -333,7 +331,6 @@ fn test_mkdirat_success_path() {
 
 #[test]
 #[cfg(not(any(target_os = "redox", target_os = "haiku")))]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_mkdirat_success_mode() {
     let expected_bits =
         stat::SFlag::S_IFDIR.bits() | stat::Mode::S_IRWXU.bits();
@@ -374,7 +371,6 @@ fn test_mkdirat_fail() {
     target_os = "redox",
     target_os = "solaris"
 )))]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_mknod() {
     use stat::{lstat, mknod, SFlag};
 
@@ -395,7 +391,6 @@ fn test_mknod() {
     target_os = "haiku",
     target_os = "redox"
 )))]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_mknodat() {
     use fcntl::{AtFlags, OFlag};
     use nix::dir::Dir;

test/test_unistd.rs

@@ -516,7 +516,6 @@ fn test_getcwd() {
 }
 
 #[test]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_chown() {
     // Testing for anything other than our own UID/GID is hard.
     let uid = Some(getuid());
@@ -551,7 +550,6 @@ fn test_fchown() {
 
 #[test]
 #[cfg(not(target_os = "redox"))]
-#[cfg_attr(target_os = "cygwin", ignore)]
 fn test_fchownat() {
     use nix::fcntl::AtFlags;
     use nix::fcntl::AT_FDCWD;