Optimize and generalize find_version

- Rm the process of collecting into `BTreeMap` in `find_version`.
 - Accept any type that implements trait `Version`

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

src/drivers/crates_io.rs

@@ -34,22 +34,8 @@ pub async fn fetch_crate_cratesio(
         })?;
 
     // Locate matching version
-    let version_iter =
-        base_info
-            .versions
-            .iter()
-            .filter_map(|v| if !v.yanked { Some(&v.num) } else { None });
-    let version_name = find_version(version_req, version_iter)?;
-
-    // Fetch information for the filtered version
-    let version = base_info
-        .versions
-        .iter()
-        .find(|v| v.num == version_name.to_string())
-        .ok_or_else(|| BinstallError::VersionUnavailable {
-            crate_name: name.into(),
-            v: version_name.clone(),
-        })?;
+    let version_iter = base_info.versions.iter().filter(|v| !v.yanked);
+    let (version, version_name) = find_version(version_req, version_iter)?;
 
     debug!("Found information for crate version: '{}'", version.num);
 

src/drivers/version.rs

@@ -1,48 +1,56 @@
-use std::collections::BTreeSet;
-
 use log::debug;
-use semver::{Version, VersionReq};
+use semver::VersionReq;
 
 use crate::BinstallError;
 
-pub(super) fn find_version<'a, V: Iterator<Item = &'a String>>(
+pub(super) trait Version {
+    /// Return `None` on error.
+    fn get_version(&self) -> Option<semver::Version>;
+}
+
+impl<T: Version> Version for &T {
+    fn get_version(&self) -> Option<semver::Version> {
+        (*self).get_version()
+    }
+}
+
+impl Version for crates_io_api::Version {
+    fn get_version(&self) -> Option<semver::Version> {
+        // Remove leading `v` for git tags
+        let ver_str = match self.num.strip_prefix('s') {
+            Some(v) => v,
+            None => &self.num,
+        };
+
+        // Parse out version
+        semver::Version::parse(ver_str).ok()
+    }
+}
+
+pub(super) fn find_version<Item: Version, VersionIter: Iterator<Item = Item>>(
     requirement: &str,
-    version_iter: V,
-) -> Result<Version, BinstallError> {
+    version_iter: VersionIter,
+) -> Result<(Item, semver::Version), BinstallError> {
     // Parse version requirement
     let version_req = VersionReq::parse(requirement).map_err(|err| BinstallError::VersionReq {
         req: requirement.into(),
         err,
     })?;
 
-    // Filter for matching versions
-    let filtered: BTreeSet<_> = version_iter
-        .filter_map(|v| {
-            // Remove leading `v` for git tags
-            let ver_str = match v.strip_prefix('s') {
-                Some(v) => v,
-                None => v,
-            };
-
-            // Parse out version
-            let ver = Version::parse(ver_str).ok()?;
-            debug!("Version: {:?}", ver);
+    version_iter
+        // Filter for matching versions
+        .filter_map(|item| {
+            let ver = item.get_version()?;
 
             // Filter by version match
             if version_req.matches(&ver) {
-                Some(ver)
+                debug!("Version: {:?}", ver);
+                Some((item, ver))
             } else {
                 None
             }
         })
-        .collect();
-
-    debug!("Filtered: {:?}", filtered);
-
-    // Return highest version
-    filtered
-        .iter()
-        .max()
-        .cloned()
+        // Return highest version
+        .max_by_key(|(_item, ver)| ver.clone())
         .ok_or(BinstallError::VersionMismatch { req: version_req })
 }