Function createMockAdapter

packages/ai/tests/test-utils.ts:151–217

(options: {
  chatStreamFn?: (opts: any) => AsyncIterable<StreamChunk>
  /** Array of chunk sequences: chatStream returns iterations[0] on first call, iterations[1] on second, etc. */
  iterations?: Array<Array<StreamChunk>>
  structuredOutput?: (opts: any) => Promise<{ data: unknown; rawText: string }>
  /** Optional native streaming structured output. When omitted, the adapter
   *  has no `structuredOutputStream` and consumers fall through to the
   *  synthesized fallback in `runStructuredFinalization`. */
  structuredOutputStream?: (opts: any) => AsyncIterable<StreamChunk>
  /** When true, the adapter declares it natively combines tools + a
   *  schema-constrained final answer in one streaming call (issue #605).
   *  The engine then forwards `outputSchema` into `chatStream` and skips
   *  the separate finalization round-trip. */
  supportsCombinedToolsAndSchema?: boolean
})

 */
// eslint-disable-next-line @typescript-eslint/no-explicit-any -- mock adapter callbacks receive internal SDK types
export function createMockAdapter(options: {
  chatStreamFn?: (opts: any) => AsyncIterable<StreamChunk>
  /** Array of chunk sequences: chatStream returns iterations[0] on first call, iterations[1] on second, etc. */
  iterations?: Array<Array<StreamChunk>>
  structuredOutput?: (opts: any) => Promise<{ data: unknown; rawText: string }>
  /** Optional native streaming structured output. When omitted, the adapter
   *  has no `structuredOutputStream` and consumers fall through to the
   *  synthesized fallback in `runStructuredFinalization`. */
  structuredOutputStream?: (opts: any) => AsyncIterable<StreamChunk>
  /** When true, the adapter declares it natively combines tools + a
   *  schema-constrained final answer in one streaming call (issue #605).
   *  The engine then forwards `outputSchema` into `chatStream` and skips
   *  the separate finalization round-trip. */
  supportsCombinedToolsAndSchema?: boolean
}) {
  const calls: Array<TextOptions<any, any>> = []
  let callIndex = 0

  const adapter: AnyTextAdapter = {
    kind: 'text' as const,
    name: 'mock',
    model: 'test-model' as const,
    '~types': {
      providerOptions: {} as Record<string, unknown>,
      inputModalities: ['text'] as readonly ['text'],
      messageMetadataByModality: {
        text: undefined as unknown,
        image: undefined as unknown,
        audio: undefined as unknown,
        video: undefined as unknown,
        document: undefined as unknown,
      },
      toolCapabilities: [] as ReadonlyArray<string>,
      toolCallMetadata: undefined as unknown,
      systemPromptMetadata: undefined as never,
    },
    chatStream: (opts: any) => {
      calls.push(opts)

      if (options.chatStreamFn) {
        return options.chatStreamFn(opts)
      }

      if (options.iterations) {
        const chunks = options.iterations[callIndex] || []
        callIndex++
        return (async function* () {
          for (const c of chunks) yield c
        })()
      }

      return (async function* () {})()
    },
    structuredOutput:
      options.structuredOutput ?? (async () => ({ data: {}, rawText: '{}' })),
  }

  if (options.structuredOutputStream) {