fix: Limiting prerelease match semantics to use only on OptVersionReq::Req

Author: linyihai

src/cargo/util/semver_ext.rs

@@ -111,13 +111,17 @@ impl OptVersionReq {
         }
     }
 
-    /// Since Semver does not support prerelease versions,
-    /// the simplest implementation is taken here without comparing the prerelease section.
-    /// The logic here is temporary, we'll have to consider more boundary conditions later,
-    /// and we're not sure if this part of the functionality should be implemented in semver or cargo.
+    /// An interim approach allows to update to SemVer-Compatible prerelease version.
     pub fn matches_prerelease(&self, version: &Version) -> bool {
+        // Others Non `OptVersionReq::Req` have their own implementation.
+        if !matches!(self, OptVersionReq::Req(_)) {
+            return self.matches(version);
+        }
+
+        // TODO: In the future we have a prerelease semantic to be implemented.
         if version.is_prerelease() {
-            let mut version = version.clone();
+            let mut version: Version = version.clone();
+            // Ignores the Prerelease tag to unlock the limit of non prerelease unpdate to prerelease.
             version.pre = semver::Prerelease::EMPTY;
             return self.matches(&version);
         }
@@ -251,9 +255,9 @@ mod matches_prerelease {
         assert!(req.matches_prerelease(&to_ver));
 
         let req = OptVersionReq::Locked(to_ver.clone(), req_ver.clone());
-        assert!(!req.matches_prerelease(&to_ver));
+        assert!(req.matches_prerelease(&to_ver));
 
         let req = OptVersionReq::Precise(to_ver.clone(), req_ver.clone());
-        assert!(!req.matches_prerelease(&to_ver));
+        assert!(req.matches_prerelease(&to_ver));
     }
 }