--- a/rust/hg-core/src/utils.rs	Mon Dec 07 18:06:53 2020 +0100
+++ b/rust/hg-core/src/utils.rs	Fri Dec 04 17:27:10 2020 +0100
@@ -167,3 +167,12 @@
         self.as_bytes().escaped_bytes()
     }
 }
+
+// TODO: use the str method when we require Rust 1.45
+pub(crate) fn strip_suffix<'a>(s: &'a str, suffix: &str) -> Option<&'a str> {
+    if s.ends_with(suffix) {
+        Some(&s[..s.len() - suffix.len()])
+    } else {
+        None
+    }
+}