test: add type tests

test/typings/ws.test-d.ts

@@ -0,0 +1,156 @@
+import { it, expectTypeOf } from 'vitest'
+import {
+  WebSocketData,
+  WebSocketLink,
+  WebSocketHandlerConnection,
+  ws,
+} from 'msw'
+import { WebSocketClientConnectionProtocol } from '@mswjs/interceptors/WebSocket'
+
+it('supports URL as the link argument', () => {
+  expectTypeOf(ws.link('ws://localhost')).toEqualTypeOf<WebSocketLink>()
+})
+
+it('supports RegExp as the link argument', () => {
+  expectTypeOf(ws.link(/\/ws$/)).toEqualTypeOf<WebSocketLink>()
+})
+
+it('exposes root-level link APIs', () => {
+  const link = ws.link('ws://localhost')
+
+  expectTypeOf(link.addEventListener).toBeFunction()
+  expectTypeOf(link.broadcast).toBeFunction()
+  expectTypeOf(link.broadcastExcept).toBeFunction()
+  expectTypeOf(link.clients).toEqualTypeOf<
+    Set<WebSocketClientConnectionProtocol>
+  >()
+})
+
+it('supports "connection" event listener', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', (connection) => {
+    expectTypeOf(connection).toEqualTypeOf<WebSocketHandlerConnection>()
+  })
+})
+
+it('errors on arbitrary event names passed to the link', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener(
+    // @ts-expect-error Unknown event name "abc".
+    'abc',
+    () => {},
+  )
+})
+
+/**
+ * Client API.
+ */
+
+it('exposes root-level "client" APIs', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ client }) => {
+    expectTypeOf(client.id).toBeString()
+    expectTypeOf(client.socket).toEqualTypeOf<WebSocket>()
+    expectTypeOf(client.url).toEqualTypeOf<URL>()
+
+    expectTypeOf(client.addEventListener).toBeFunction()
+    expectTypeOf(client.send).toBeFunction()
+    expectTypeOf(client.removeEventListener).toBeFunction()
+    expectTypeOf(client.close).toBeFunction()
+  })
+})
+
+it('supports "message" event listener on the client', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ client }) => {
+    client.addEventListener('message', (event) => {
+      expectTypeOf(event).toEqualTypeOf<MessageEvent<WebSocketData>>()
+    })
+  })
+})
+
+it('supports "close" event listener on the client', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ client }) => {
+    client.addEventListener('close', (event) => {
+      expectTypeOf(event).toMatchTypeOf<CloseEvent>()
+    })
+  })
+})
+
+it('errors on arbitrary event names passed to the client', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ client }) => {
+    client.addEventListener(
+      // @ts-expect-error Unknown event name "abc".
+      'abc',
+      () => {},
+    )
+  })
+})
+
+/**
+ * Server API.
+ */
+
+it('exposes root-level "server" APIs', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ server }) => {
+    expectTypeOf(server.socket).toEqualTypeOf<WebSocket>()
+
+    expectTypeOf(server.connect).toEqualTypeOf<() => void>()
+    expectTypeOf(server.addEventListener).toBeFunction()
+    expectTypeOf(server.send).toBeFunction()
+    expectTypeOf(server.removeEventListener).toBeFunction()
+    expectTypeOf(server.close).toBeFunction()
+  })
+})
+
+it('supports "message" event listener on the server', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ server }) => {
+    server.addEventListener('message', (event) => {
+      expectTypeOf(event).toEqualTypeOf<MessageEvent<WebSocketData>>()
+    })
+  })
+})
+
+it('supports "open" event listener on the server', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ server }) => {
+    server.addEventListener('open', (event) => {
+      expectTypeOf(event).toMatchTypeOf<Event>()
+    })
+  })
+})
+
+it('supports "close" event listener on the server', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ server }) => {
+    server.addEventListener('close', (event) => {
+      expectTypeOf(event).toMatchTypeOf<CloseEvent>()
+    })
+  })
+})
+
+it('errors on arbitrary event names passed to the server', () => {
+  const link = ws.link('ws://localhost')
+
+  link.addEventListener('connection', ({ server }) => {
+    server.addEventListener(
+      // @ts-expect-error Unknown event name "abc".
+      'abc',
+      () => {},
+    )
+  })
+})