api-types: rework BackupNamespace::map_prefix

to use slice::strip_prefix() from std

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

pbs-api-types/src/datastore.rs

@@ -702,25 +702,22 @@ impl BackupNamespace {
         source_prefix: &BackupNamespace,
         target_prefix: &BackupNamespace,
     ) -> Result<Self, Error> {
-        let mut mapped = target_prefix.clone();
+        let suffix = self
-        let mut source_iter = source_prefix.components();
+            .inner
-        let mut self_iter = self.components();
+            .strip_prefix(&source_prefix.inner[..])
-
+            .ok_or_else(|| {
-        while let Some(comp) = self_iter.next() {
+                format_err!(
-            if let Some(source_comp) = source_iter.next() {
-                if source_comp != comp {
-                    bail!(
                     "Failed to map namespace - {} is not a valid prefix of {}",
                     source_prefix,
                     self
-                    );
+                )
-                }
+            })?;
-                continue;
-            }
-            mapped.push(comp.to_owned())?;
-        }
 
-        Ok(mapped)
+        let mut new = target_prefix.clone();
+        for item in suffix {
+            new.push(item.clone())?;
+        }
+        Ok(new)
     }
 }