fix(sync): wait until persistence adapters ready before first sync

packages/signaldb/__tests__/helpers/memoryPersistenceAdapter.ts

@@ -0,0 +1,64 @@
+import type { PersistenceAdapter } from '../../src'
+
+export default function memoryPersistenceAdapter<
+  T extends { id: I } & Record<string, any>,
+  I = any,
+>(
+  initialData: T[] = [],
+  transmitChanges = false,
+) {
+  // not really a "persistence adapter", but it works for testing
+  let items = [...initialData]
+  const changes: {
+    added: T[],
+    modified: T[],
+    removed: T[],
+  } = {
+    added: [],
+    modified: [],
+    removed: [],
+  }
+  let onChange: () => void | Promise<void> = () => { /* do nothing */ }
+  return {
+    register: (changeCallback: () => void | Promise<void>) => {
+      onChange = changeCallback
+      return Promise.resolve()
+    },
+    load: () => {
+      const currentChanges = { ...changes }
+      changes.added = []
+      changes.modified = []
+      changes.removed = []
+      const hasChanges = currentChanges.added.length > 0
+        || currentChanges.modified.length > 0
+        || currentChanges.removed.length > 0
+      if (transmitChanges && hasChanges) {
+        return Promise.resolve({ changes: currentChanges })
+      }
+      return Promise.resolve({ items })
+    },
+    save: (newSnapshot: T[]) => {
+      items = [...newSnapshot]
+      return Promise.resolve()
+    },
+    addNewItem: (item: T) => {
+      items.push(item)
+      changes.added.push(item)
+      void onChange()
+    },
+    changeItem: (item: T) => {
+      items = items.map(i => (i.id === item.id ? item : i))
+      changes.modified.push(item)
+      void onChange()
+    },
+    removeItem: (item: T) => {
+      items = items.filter(i => i.id !== item.id)
+      changes.removed.push(item)
+      void onChange()
+    },
+  } as (PersistenceAdapter<T, I> & {
+    addNewItem: (item: T) => void,
+    changeItem: (item: T) => void,
+    removeItem: (item: T) => void,
+  })
+}

packages/signaldb/__tests__/persistence.spec.ts

@@ -1,69 +1,8 @@
 import fs from 'fs/promises'
 import { describe, it, expect, vi } from 'vitest'
-import type { PersistenceAdapter } from '../src'
 import { Collection, createFilesystemAdapter } from '../src'
 import waitForEvent from './helpers/waitForEvent'
-
-// eslint-disable-next-line max-len
-function memoryPersistenceAdapter<T extends { id: I } & Record<string, any>, I = any>(
-  initialData: T[] = [],
-  transmitChanges = false,
-) {
-  // not really a "persistence adapter", but it works for testing
-  let items = [...initialData]
-  const changes: {
-    added: T[],
-    modified: T[],
-    removed: T[],
-  } = {
-    added: [],
-    modified: [],
-    removed: [],
-  }
-  let onChange: () => void | Promise<void> = () => { /* do nothing */ }
-  return {
-    register: (changeCallback: () => void | Promise<void>) => {
-      onChange = changeCallback
-      return Promise.resolve()
-    },
-    load: () => {
-      const currentChanges = { ...changes }
-      changes.added = []
-      changes.modified = []
-      changes.removed = []
-      const hasChanges = currentChanges.added.length > 0
-        || currentChanges.modified.length > 0
-        || currentChanges.removed.length > 0
-      if (transmitChanges && hasChanges) {
-        return Promise.resolve({ changes: currentChanges })
-      }
-      return Promise.resolve({ items })
-    },
-    save: (newSnapshot: T[]) => {
-      items = [...newSnapshot]
-      return Promise.resolve()
-    },
-    addNewItem: (item: T) => {
-      items.push(item)
-      changes.added.push(item)
-      void onChange()
-    },
-    changeItem: (item: T) => {
-      items = items.map(i => (i.id === item.id ? item : i))
-      changes.modified.push(item)
-      void onChange()
-    },
-    removeItem: (item: T) => {
-      items = items.filter(i => i.id !== item.id)
-      changes.removed.push(item)
-      void onChange()
-    },
-  } as (PersistenceAdapter<T, I> & {
-    addNewItem: (item: T) => void,
-    changeItem: (item: T) => void,
-    removeItem: (item: T) => void,
-  })
-}
+import memoryPersistenceAdapter from './helpers/memoryPersistenceAdapter'
 
 describe('Persistence', () => {
   it('should load items from persistence adapter', async () => {