test folder-deleting guards

ethcore/src/snapshot/service.rs

@@ -296,7 +296,7 @@ impl Service {
 	fn replace_client_db(&self) -> Result<(), Error> {
 		let our_db = self.restoration_db();
 
-		try!(self.db_restore.restore_db(our_db.to_str().unwrap()));
+		try!(self.db_restore.restore_db(our_db.to_string_lossy()));
 		Ok(())
 	}
 

ethcore/src/snapshot/tests/service.rs

@@ -21,7 +21,7 @@ use std::sync::Arc;
 use client::{BlockChainClient, Client};
 use ids::BlockID;
 use snapshot::service::{Service, ServiceParams};
-use snapshot::SnapshotService;
+use snapshot::{self, ManifestData, SnapshotService};
 use spec::Spec;
 use tests::helpers::generate_dummy_client_with_spec_and_data;
 
@@ -29,6 +29,14 @@ use devtools::RandomTempPath;
 use io::IoChannel;
 use util::kvdb::DatabaseConfig;
 
+struct NoopDBRestore;
+
+impl snapshot::DatabaseRestore for NoopDBRestore {
+	fn restore_db(&self, _new_db: &str) -> Result<(), ::error::Error> {
+		Ok(())
+	}
+}
+
 #[test]
 fn restored_is_equivalent() {
 	const NUM_BLOCKS: u32 = 400;
@@ -93,4 +101,41 @@ fn restored_is_equivalent() {
 
 		assert_eq!(block1, block2);
 	}
-}
+}
+
+#[test]
+fn guards_delete_folders() {
+	let spec = Spec::new_null();
+	let path = RandomTempPath::create_dir();
+	let mut path = path.as_path().clone();
+	let service_params = ServiceParams {
+		engine: spec.engine.clone(),
+		genesis_block: spec.genesis_block(),
+		db_config: DatabaseConfig::with_columns(::db::NUM_COLUMNS),
+		pruning: ::util::journaldb::Algorithm::Archive,
+		channel: IoChannel::disconnected(),
+		snapshot_root: path.clone(),
+		db_restore: Arc::new(NoopDBRestore),
+	};
+
+	let service = Service::new(service_params).unwrap();
+	path.push("restoration");
+
+	let manifest = ManifestData {
+		state_hashes: vec![],
+		block_hashes: vec![],
+		block_number: 0,
+		block_hash: Default::default(),
+		state_root: Default::default(),
+	};
+
+	service.init_restore(manifest).unwrap();
+
+	assert!(path.exists());
+
+	drop(service);
+
+	assert!(!path.exists());
+}
+
+#[test]