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Testing

In the test environment, psychic-websockets automatically selects InProcessWebsocketsAdapter. Every ws.emit(...) call is recorded in-process — no Redis connection is needed. Three helpers from @rvoh/psychic-websockets/testing let you assert on those recordings.

import { assertBroadcast, clearBroadcasts, websocketBroadcasts } from '@rvoh/psychic-websockets/testing'

Setup​

Call clearBroadcasts() in a beforeEach so each test starts with an empty buffer:

beforeEach(() => {
  clearBroadcasts()
})

assertBroadcast​

Asserts that at least one recorded broadcast matches the given path and optional constraints. Throws a descriptive error if none matched.

// path only
assertBroadcast('/users/ping')

// path + recipient
assertBroadcast('/users/ping', { to: user.id })

// path + payload
assertBroadcast('/users/alert', { data: { message: 'hello' } })

// path + recipient + payload
assertBroadcast('/users/alert', { to: user.id, data: { message: 'hello' } })

data is compared with deep strict equality. The optional prefix option sets the Redis key prefix (default: 'user', matching Ws's default) — only relevant if you override it in your app.

websocketBroadcasts​

Returns all recorded broadcasts in emit order, optionally filtered to a single path:

// all broadcasts
const all = websocketBroadcasts()

// filtered to one path
const pings = websocketBroadcasts('/users/ping')

// custom assertion on the array
expect(pings).toHaveLength(2)
expect(pings[0].userKey).toBe(`user:${user.id}`)

Combining with vi.spyOn​

These helpers and vi.spyOn(ws, 'emit') are not mutually exclusive. Use assertBroadcast / websocketBroadcasts when you want to assert on what was actually dispatched through the adapter; use a spy when you want to assert on call arguments or prevent the emit from running at all.