move client from separate repo

client/tests/mocks/bootstrapper.mock.ts

@@ -0,0 +1,26 @@
+import { Bootstrapper, DBCache } from '../../lib/patch-db'
+
+export class MockBootstrapper<T> implements Bootstrapper<T> {
+
+  constructor (
+    private sequence: number = 0,
+    private data: T = { } as T,
+  ) { }
+
+  async init (): Promise<DBCache<T>> {
+    return {
+      sequence: this.sequence,
+      data: this.data as T,
+    }
+  }
+
+  async update (cache: DBCache<T>): Promise<void> {
+    this.sequence = cache.sequence
+    this.data = cache.data
+  }
+
+  async clear (): Promise<void> {
+    this.sequence = 0
+    this.data = { } as T
+  }
+}