spy · Docs - Routecraft

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spy<T>(): SpyAdapter<T>

Records all exchanges passing through it. Use as a destination (.to() / .tap(), void send), enricher (.enrich(); the fetch face returns the current body, so a bare .enrich(spy()) observes without changing it), or processor to capture and assert on pipeline output.

import { spy } from '@routecraft/testing'

const spyAdapter = spy()

const route = craft()
  .id('my-route')
  .from(simple('payload'))
  .to(spyAdapter)

const t = await testContext().routes(route).build()
await t.test()

expect(spyAdapter.received).toHaveLength(1)
expect(spyAdapter.received[0].body).toBe('payload')
expect(spyAdapter.calls.send).toBe(1)

Properties:

Field	Type	Default	Required	Description
`received`	`Exchange[]`	`[]`	No	All exchanges recorded
`calls.send`	`number`	`0`	No	Number of times used as destination
`calls.process`	`number`	`0`	No	Number of times used as processor
`calls.enrich`	`number`	`0`	No	Number of times used as enricher

Methods:

Method	Returns	Description
`reset()`	`void`	Clear all recorded data
`lastReceived()`	`Exchange`	Most recent exchange
`receivedBodies()`	`unknown[]`	Array of just the body values

See Testing for full usage patterns.