compare library versions

daedalus/Cargo.toml

@@ -29,6 +29,7 @@ sha1 = { version = "0.6.1", features = ["std"] }
 bincode = { version = "2.0.0-rc.3", features = ["serde"], optional = true }
 once_cell = "1"
 url = "2"
+lenient_semver = "0"
 
 [build-dependencies]
 dotenvy = "0.15.6"

daedalus/src/lib.rs

@@ -5,7 +5,8 @@
 #![warn(missing_docs, unused_import_braces, missing_debug_implementations)]
 
 use std::{
-    convert::TryFrom, fmt::Display, path::PathBuf, str::FromStr, time::Duration,
+    cmp::Ordering, convert::TryFrom, fmt::Display, path::PathBuf, str::FromStr,
+    time::Duration,
 };
 
 use backon::{ExponentialBuilder, Retryable};
@@ -178,6 +179,24 @@ impl GradleSpecifier {
     pub fn is_log4j(&self) -> bool {
         self.package.as_str() == "org.apache.logging.log4j"
     }
+
+    /// Compares two versions
+    /// Returns Ordering::Equal if they are equal
+    /// Returns Ordering::Greater if self is greater than other
+    /// Returns Ordering::Less if self is less than other
+    pub fn compare_versions(&self, other: &Self) -> Result<Ordering, Error> {
+        let x = lenient_semver::parse(self.version.as_str());
+        let y = lenient_semver::parse(other.version.as_str());
+
+        if x.is_err() || y.is_err() {
+            return Err(Error::ParseError(
+                "Unable to parse version".to_string(),
+            ));
+        }
+
+        // safe to unwrap because we already checked for errors
+        Ok(x.unwrap().cmp(&y.unwrap()))
+    }
 }
 
 impl FromStr for GradleSpecifier {