reference.md

Testing your Ferp App

tester export

The exported tester is a function that returns an instance of the tester object. It can accept an initial state, but that's optional.

tester object, as t

Setup functions

The setup functions will always return the tester object for chaining.

t.includeEffectNone()

By default, the test interface does not include checking against none effects, since they only represent when there are no more effects to chain. Calling includeEffectNone disables this behaviour.

t.willAct(actionAnnotation)

willAct adds an expectation that an action named actionAnnotation will be dispatched at some point. The annotation can be an annotation specified by the effects.act(fn, annotation) call, fn.alias, or finally fn.name.

t.willThunk(thunkAnnotation)

willThunk adds an expectation that an thunk named thunkAnnotation will be dispatched at some point. The annotation can be an annotation specified by the effects.thunk(fn, annotation) call, fn.alias, or finally fn.name.

t.willDefer(deferAnnotation)

willDefer adds an expectation that an thunk named deferAnnotation will be dispatched at some point. The annotation can be an annotation specified by the effects.defer(fnOrPromise, annotation).

t.willBatch(annotation)

willBatch adds an expectation that an batch named batchAnnotation will be dispatched at some point. The annotation can be an annotation specified by the effects.batch(array, annotation).

Executors

t.fromEffect(effect)

fromEffect is an asyncronous function that runs either the top level effect, or all effects if resolveAllEffects was called previously. fromEffect returns the tester object after resolving all of the effects scheduled to run.

t.fromAction(action)

fromAction runs t.fromEffect(effects.act(action)) behind the scenes.

t.fromSubscription(subscription)

fromSubscription accepts a declared subscription, in the form of [subscriptionFx, prop1, prop2, ...]. While fromSubscription is not asyncronous, you can still await it so it aligns with the other executors. The tester object returned has a special cancel method to call the subscription cancel function for testing purposes.

Assertions

t.ok()

If all expectations were met, this will return true, otherwise it will return false

t.failedOn()

This returns an array of failed expectations, in the form of [{ type: effectType, annotation: '' }, ...].

t.missed()

This returns an array of missed expectations, in the form of [{ type: effectType, annotation: '' }, ...]. These can be ignored, but may hint at further expecations you can add to your test.

t.state()

If an initial state was set in the exported tester() function, state() will return a copy of state with any modifications ran by any actions during the test. If no actions were set, and no actions were ran, this will return an empty object, {}.