diff --git a/src/uucore/signals.rs b/src/uucore/signals.rs
index 8887ddfe1..76a153a03 100644
--- a/src/uucore/signals.rs
+++ b/src/uucore/signals.rs
@@ -325,21 +325,65 @@ pub static ALL_SIGNALS: [Signal<'static>; 31] = [
 ];
 
 pub fn signal_by_name_or_value(signal_name_or_value: &str) -> Option<usize> {
-    if signal_name_or_value == "0" {
-        return Some(0);
-    }
-    for signal in &ALL_SIGNALS {
-        let long_name = format!("SIG{}", signal.name);
-        if signal.name == signal_name_or_value || (signal_name_or_value == signal.value.to_string())
-            || (long_name == signal_name_or_value)
-        {
-            return Some(signal.value);
+    if let Ok(value) = signal_name_or_value.parse() {
+        if is_signal(value) {
+            return Some(value);
+        } else {
+            return None;
         }
     }
-    None
+    let signal_name = signal_name_or_value.trim_left_matches("SIG");
+
+    ALL_SIGNALS
+        .iter()
+        .find(|s| s.name == signal_name)
+        .map(|s| s.value)
 }
 
 #[inline(always)]
 pub fn is_signal(num: usize) -> bool {
-    num < ALL_SIGNALS.len()
+    // Named signals start at 1
+    num <= ALL_SIGNALS.len()
+}
+
+#[test]
+fn signals_all_contiguous() {
+    for (i, signal) in ALL_SIGNALS.iter().enumerate() {
+        assert_eq!(signal.value, i + 1);
+    }
+}
+
+#[test]
+fn signals_all_are_signal() {
+    for signal in &ALL_SIGNALS {
+        assert!(is_signal(signal.value));
+    }
+}
+
+#[test]
+fn signal_by_value() {
+    assert_eq!(signal_by_name_or_value("0"), Some(0));
+    for signal in &ALL_SIGNALS {
+        assert_eq!(
+            signal_by_name_or_value(&signal.value.to_string()),
+            Some(signal.value)
+        );
+    }
+}
+
+#[test]
+fn signal_by_short_name() {
+    for signal in &ALL_SIGNALS {
+        assert_eq!(signal_by_name_or_value(signal.name), Some(signal.value));
+    }
+}
+
+#[test]
+fn signal_by_long_name() {
+    for signal in &ALL_SIGNALS {
+        assert_eq!(
+            signal_by_name_or_value(&format!("SIG{}", signal.name)),
+            Some(signal.value)
+        );
+    }
 }