Add local CAS cleanup policy

crates/geth-cas/src/lib.rs

@@ -67,6 +67,15 @@ impl LocalCas {
         Ok(self.blob_path(hash)?.exists())
     }
 
+    pub fn remove(&self, hash: &BlobHash) -> Result<bool, CasError> {
+        let path = self.blob_path(hash)?;
+        if !path.exists() {
+            return Ok(false);
+        }
+        std::fs::remove_file(path)?;
+        Ok(true)
+    }
+
     pub fn list(&self) -> Result<Vec<BlobInfo>, CasError> {
         let blobs = self.root.join("blobs");
         if !blobs.exists() {
@@ -154,4 +163,15 @@ mod tests {
         cas.get_to_path(&info.hash, &out).expect("get");
         assert_eq!(std::fs::read(out).expect("read"), b"hello geth");
     }
+
+    #[test]
+    fn cas_remove_deletes_blob_file() {
+        let dir = tempfile::tempdir().expect("tempdir");
+        let cas = LocalCas::new(dir.path());
+        let info = cas.add_bytes(b"remove me").expect("add");
+
+        assert!(cas.remove(&info.hash).expect("remove"));
+        assert!(!cas.has(&info.hash).expect("has after remove"));
+        assert!(!cas.remove(&info.hash).expect("remove missing"));
+    }
 }