M1: reject leading-zero numeric prerelease versions

xtask/src/version.rs

@@ -49,7 +49,12 @@ pub fn validate(v: &str) -> Result<(), String> {
         return bad();
     }
     if let Some(p) = pre
-        && (p.is_empty() || p.split('.').any(|id| id.is_empty() || !id.bytes().all(|b| b.is_ascii_alphanumeric() || b == b'-')))
+        && (p.is_empty()
+            || p.split('.').any(|id| {
+                id.is_empty()
+                    || !id.bytes().all(|b| b.is_ascii_alphanumeric() || b == b'-')
+                    || (id.len() > 1 && id.starts_with('0') && id.bytes().all(|b| b.is_ascii_digit()))
+            }))
     {
         return bad();
     }
@@ -144,6 +149,18 @@ mod tests {
         assert!(replace(MANIFEST, "nope").is_err());
     }
 
+    #[test]
+    fn numeric_prerelease_identifiers_have_no_leading_zeroes() {
+        for bad in ["1.0.0-00", "1.0.0-01", "1.0.0-rc.01"] {
+            assert!(validate(bad).is_err(), "{bad}");
+            assert!(replace(MANIFEST, bad).is_err(), "{bad} must not reach the manifest");
+        }
+        for ok in ["1.0.0-0", "1.0.0-rc.0", "1.0.0-01a", "1.0.0-0-1"] {
+            assert!(validate(ok).is_ok(), "{ok}");
+            assert_eq!(read(&replace(MANIFEST, ok).unwrap()).unwrap(), ok);
+        }
+    }
+
     #[test]
     fn the_real_manifest_has_a_valid_version() {
         let text = std::fs::read_to_string(crate::root().join("Cargo.toml")).unwrap();