refactor: implement From Cow trait for the InternedString

Signed-off-by: 0xPoe <techregister@pm.me>

Author: 0xPoe

src/cargo/core/compiler/fingerprint/mod.rs

@@ -694,7 +694,7 @@ impl<'de> Deserialize<'de> for DepFingerprint {
         let (pkg_id, name, public, hash) = <(u64, String, bool, u64)>::deserialize(d)?;
         Ok(DepFingerprint {
             pkg_id,
-            name: InternedString::new(&name),
+            name: name.into(),
             public,
             fingerprint: Arc::new(Fingerprint {
                 memoized_hash: Mutex::new(Some(hash)),

src/cargo/sources/registry/index/mod.rs

@@ -264,35 +264,23 @@ impl IndexPackage<'_> {
     fn to_summary(&self, source_id: SourceId) -> CargoResult<Summary> {
         // ****CAUTION**** Please be extremely careful with returning errors, see
         // `IndexSummary::parse` for details
-        let pkgid = PackageId::new(
-            InternedString::new(&self.name),
-            self.vers.clone(),
-            source_id,
-        );
+        let pkgid = PackageId::new(self.name.as_ref().into(), self.vers.clone(), source_id);
         let deps = self
             .deps
             .iter()
             .map(|dep| dep.clone().into_dep(source_id))
             .collect::<CargoResult<Vec<_>>>()?;
         let mut features = self.features.clone();
-        if let Some(features2) = &self.features2 {
+        if let Some(features2) = self.features2.clone() {
             for (name, values) in features2 {
-                features
-                    .entry(name.clone())
-                    .or_default()
-                    .extend(values.iter().cloned());
+                features.entry(name).or_default().extend(values);
             }
         }
         let features = features
             .into_iter()
-            .map(|(name, values)| {
-                (
-                    InternedString::new(&name),
-                    values.iter().map(|v| InternedString::new(&v)).collect(),
-                )
-            })
+            .map(|(name, values)| (name.into(), values.into_iter().map(|v| v.into()).collect()))
             .collect::<BTreeMap<_, _>>();
-        let links = self.links.as_ref().map(|l| InternedString::new(&l));
+        let links: Option<InternedString> = self.links.as_ref().map(|l| l.as_ref().into());
         let mut summary = Summary::new(pkgid, deps, &features, links, self.rust_version.clone())?;
         summary.set_checksum(self.cksum.clone());
         Ok(summary)

src/cargo/util/interning.rs

@@ -47,7 +47,7 @@ impl<'a> From<&'a String> for InternedString {
 
 impl From<String> for InternedString {
     fn from(item: String) -> Self {
-        InternedString::from_cow(item.into())
+        InternedString::from(Cow::Owned(item))
     }
 }
 
@@ -69,14 +69,8 @@ impl<'a> PartialEq<&'a str> for InternedString {
     }
 }
 
-impl Eq for InternedString {}
-
-impl InternedString {
-    pub fn new(s: &str) -> InternedString {
-        InternedString::from_cow(s.into())
-    }
-
-    fn from_cow<'a>(cs: Cow<'a, str>) -> InternedString {
+impl<'a> From<Cow<'a, str>> for InternedString {
+    fn from(cs: Cow<'a, str>) -> Self {
         let mut cache = interned_storage();
         let s = cache.get(cs.as_ref()).copied().unwrap_or_else(|| {
             let s = cs.into_owned().leak();
@@ -86,7 +80,14 @@ impl InternedString {
 
         InternedString { inner: s }
     }
+}
+
+impl Eq for InternedString {}
 
+impl InternedString {
+    pub fn new(s: &str) -> InternedString {
+        InternedString::from(Cow::Borrowed(s))
+    }
     pub fn as_str(&self) -> &'static str {
         self.inner
     }