Function createMockConnectionAdapter

packages/ai-client/tests/test-utils.ts:83–135

(
  options: MockConnectionAdapterOptions = {},
)

 * ```
 */
export function createMockConnectionAdapter(
  options: MockConnectionAdapterOptions = {},
): ConnectConnectionAdapter {
  const {
    chunks = [],
    chunkDelay = 0,
    shouldError = false,
    error = new Error('Mock adapter error'),
    onConnect,
    onAbort,
  } = options

  return {
    async *connect(messages, data, abortSignal) {
      if (onConnect) {
        // Type assertion: messages can be ModelMessage[] or UIMessage[]
        // Filter out system messages if present
        const filteredMessages = (messages as any[]).filter(
          (m: any) => !('role' in m) || m.role !== 'system',
        )
        onConnect(filteredMessages as any, data, abortSignal)
      }

      if (shouldError) {
        throw error
      }

      for (const chunk of chunks) {
        // Check abort signal before yielding
        if (abortSignal?.aborted) {
          if (onAbort) {
            onAbort(abortSignal)
          }
          return
        }

        if (chunkDelay > 0) {
          await new Promise((resolve) => setTimeout(resolve, chunkDelay))
        }

        // Check again after delay
        if (abortSignal?.aborted) {
          if (onAbort) {
            onAbort(abortSignal)
          }
          return
        }

        yield chunk
      }
    },
  }
}

/**
 * Helper to create simple text content chunks (AG-UI format)