Add test_utils

We add a utility function needed by upcoming `KVStore` implementation
tests.

Author: tnull

lightning-persister/src/lib.rs

@@ -10,6 +10,9 @@
 
 #[cfg(ldk_bench)] extern crate criterion;
 
+#[cfg(test)]
+mod test_utils;
+
 mod util;
 
 extern crate lightning;

lightning-persister/src/test_utils.rs

@@ -0,0 +1,30 @@
+use lightning::util::persist::KVStore;
+
+pub(crate) fn do_read_write_remove_list_persist<K: KVStore>(kv_store: &K) {
+	use lightning::util::ser::Readable;
+
+	let data = [42u8; 32];
+
+	let namespace = "testspace";
+	let key = "testkey";
+
+	// Test the basic KVStore operations.
+	kv_store.write(namespace, key, &data).unwrap();
+
+	// Test empty namespace is allowed, but not empty key.
+	kv_store.write("", key, &data).unwrap();
+	assert!(kv_store.write(namespace, "", &data).is_err());
+
+	let listed_keys = kv_store.list(namespace).unwrap();
+	assert_eq!(listed_keys.len(), 1);
+	assert_eq!(listed_keys[0], key);
+
+	let mut reader = kv_store.read(namespace, key).unwrap();
+	let read_data: [u8; 32] = Readable::read(&mut reader).unwrap();
+	assert_eq!(data, read_data);
+
+	kv_store.remove(namespace, key).unwrap();
+
+	let listed_keys = kv_store.list(namespace).unwrap();
+	assert_eq!(listed_keys.len(), 0);
+}