snapshot of https://github.com/ueberdosis/hocuspocus.git @ cf3cfa355b4d3bb61c6b6c80071f71783e32470e (2026-09-15)

tests/provider/flushDelay.ts

@@ -0,0 +1,138 @@
+import test from 'ava'
+import { newHocuspocus, newHocuspocusProvider, sleep } from '../utils/index.ts'
+import { retryableAssertion } from '../utils/retryableAssertion.ts'
+
+test('batches rapid document updates into a single outgoing message', async t => {
+  const server = await newHocuspocus(t)
+  let updateMessages = 0
+
+  await new Promise(resolve => {
+    const provider = newHocuspocusProvider(t, server, {
+      awareness: null,
+      flushDelay: 100,
+      onOutgoingMessage({ message }) {
+        if (message.description === 'A document update') {
+          updateMessages += 1
+        }
+      },
+      async onSynced() {
+        provider.document.getMap('test').set('a', 1)
+        provider.document.getMap('test').set('b', 2)
+        provider.document.getMap('test').set('c', 3)
+
+        // Still inside the flush window: nothing has been sent yet.
+        t.is(updateMessages, 0)
+
+        await sleep(300)
+
+        // The three updates were merged into a single message.
+        t.is(updateMessages, 1)
+        resolve('done')
+      },
+    })
+  })
+})
+
+test('a merged batch still converges on another client', async t => {
+  const server = await newHocuspocus(t)
+
+  const provider = newHocuspocusProvider(t, server, {
+    awareness: null,
+    flushDelay: 100,
+  })
+
+  await new Promise(resolve => {
+    provider.on('synced', () => resolve('done'))
+  })
+
+  provider.document.getMap('test').set('a', 1)
+  provider.document.getMap('test').set('b', 2)
+  provider.document.getMap('test').set('c', 3)
+
+  const reader = newHocuspocusProvider(t, server, { awareness: null })
+
+  await retryableAssertion(t, tt => {
+    const map = reader.document.getMap('test')
+    tt.is(map.get('a'), 1)
+    tt.is(map.get('b'), 2)
+    tt.is(map.get('c'), 3)
+  })
+})
+
+test('sends one message per update when flushDelay is disabled', async t => {
+  const server = await newHocuspocus(t)
+  let updateMessages = 0
+
+  await new Promise(resolve => {
+    const provider = newHocuspocusProvider(t, server, {
+      awareness: null,
+      onOutgoingMessage({ message }) {
+        if (message.description === 'A document update') {
+          updateMessages += 1
+        }
+      },
+      async onSynced() {
+        provider.document.getMap('test').set('a', 1)
+        provider.document.getMap('test').set('b', 2)
+        provider.document.getMap('test').set('c', 3)
+
+        await sleep(100)
+
+        t.is(updateMessages, 3)
+        resolve('done')
+      },
+    })
+  })
+})
+
+test('reports unsynced changes during the batch window and clears after sync', async t => {
+  const server = await newHocuspocus(t)
+
+  const provider = newHocuspocusProvider(t, server, {
+    awareness: null,
+    flushDelay: 100,
+  })
+
+  await new Promise(resolve => {
+    provider.on('synced', () => resolve('done'))
+  })
+
+  provider.document.getMap('test').set('a', 1)
+  provider.document.getMap('test').set('b', 2)
+
+  // Buffered but not yet sent — still counts as unsynced.
+  t.is(provider.hasUnsyncedChanges, true)
+
+  await retryableAssertion(t, tt => {
+    tt.is(provider.hasUnsyncedChanges, false)
+  })
+})
+
+test('collapses rapid awareness changes into a single outgoing message', async t => {
+  const server = await newHocuspocus(t)
+  let awarenessMessages = 0
+
+  await new Promise(resolve => {
+    const provider = newHocuspocusProvider(t, server, {
+      flushDelay: 100,
+      onOutgoingMessage({ message }) {
+        if (message.description === 'Awareness states update') {
+          awarenessMessages += 1
+        }
+      },
+      async onSynced() {
+        // Ignore any awareness sent as part of the initial sync.
+        awarenessMessages = 0
+
+        provider.setAwarenessField('cursor', 1)
+        provider.setAwarenessField('cursor', 2)
+        provider.setAwarenessField('cursor', 3)
+
+        await sleep(300)
+
+        t.is(awarenessMessages, 1)
+        resolve('done')
+      },
+    })
+  })
+})