Move test_extend back to the previous place

src/sys/signal.rs

@@ -1144,6 +1144,19 @@ mod tests {
         assert_eq!("9".parse::<Signal>(), errval);
     }
 
+    #[test]
+    fn test_extend() {
+        let mut one_signal = SigSet::empty();
+        one_signal.add(SIGUSR1);
+
+        let mut two_signals = SigSet::empty();
+        two_signals.add(SIGUSR2);
+        two_signals.extend(&one_signal);
+
+        assert!(two_signals.contains(SIGUSR1));
+        assert!(two_signals.contains(SIGUSR2));
+    }
+
     #[test]
     #[cfg(not(target_os = "redox"))]
     fn test_thread_signal_set_mask() {
@@ -1214,19 +1227,6 @@ mod tests {
         }).join().unwrap();
     }
 
-    #[test]
-    fn test_extend() {
-        let mut one_signal = SigSet::empty();
-        one_signal.add(SIGUSR1);
-
-        let mut two_signals = SigSet::empty();
-        two_signals.add(SIGUSR2);
-        two_signals.extend(&one_signal);
-
-        assert!(two_signals.contains(SIGUSR1));
-        assert!(two_signals.contains(SIGUSR2));
-    }
-
     #[test]
     fn test_from_and_into_iterator() {
         let sigset = SigSet::from_iter(vec![Signal::SIGUSR1, Signal::SIGUSR2]);