# _replay

URL: /milo-cli/api/milo/testing/_replay/
Section: testing
Description: Action log replay (time-travel).

---

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Module

#
`testing._replay`

Action log replay (time-travel).

1Function

## Functions

`replay`

6

`Any`

▼

Replay a recorded session through a reducer.

Returns final state. Optionally a…

`def replay(recording: SessionRecording | str | Path, reducer: Callable, *, speed: float = 1.0, step: bool = False, on_state: Callable | None = None, assert_hashes: bool = False) -> Any`

Replay a recorded session through a reducer.

Returns final state. Optionally asserts state_hash matches
at each step to detect reducer regressions.

##### Parameters

Name
Type
Description

`recording`
`SessionRecording | str | Path`

`reducer`
`Callable`

`speed`
`float`

Default:`1.0`

`step`
`bool`

Default:`False`

`on_state`
`Callable | None`

Default:`None`

`assert_hashes`
`bool`

Default:`False`

##### Returns

`Any`