feat: to_cow_string for rope

Author: SyMind

src/cached_source.rs

@@ -94,7 +94,7 @@ impl<T> CachedSource<T> {
 
 impl<T: Source + Hash + PartialEq + Eq + 'static> Source for CachedSource<T> {
   fn source(&self) -> Cow<str> {
-    Cow::Owned(self.get_rope().to_string())
+    self.get_rope().to_cow_string()
   }
 
   fn rope(&self) -> Rope<'_> {

src/rope.rs

@@ -461,6 +461,20 @@ impl<'a> Rope<'a> {
       }
     }
   }
+
+  /// Converts the rope to Cow<str>.
+  pub fn to_cow_string(&self) -> Cow<str> {
+    match &self.repr {
+      Repr::Light(s) => Cow::Borrowed(s),
+      Repr::Full(data) => {
+        let mut s = String::with_capacity(self.len());
+        for (chunk, _) in data.iter() {
+          s.push_str(chunk);
+        }
+        Cow::Owned(s)
+      }
+    }
+  }
 }
 
 impl Hash for Rope<'_> {