*<s>Spinach</s> — These have been removed from our codebase in May 2018. (`/features/`)
## Karma tests `/spec/javascripts/**/*.js`
These are the more frontend-focused, at the moment. They're **faster** than `rspec` and make for very quick testing of frontend components.
### When do we write/update these tests?
When we add/update a method/action/mutation to Vue or Vuex, we write karma tests to ensure the logic we wrote doesn't break. We should, however, refrain from writing tests that double-test Vue's internal features.
### Relevant notes
Karma tests are run against a virtual DOM.
To populate the DOM, we can use fixtures to fake the generation of HTML instead of having Rails do that.
Be sure to check the [best practices for karma tests](../../testing_guide/frontend_testing.html#best-practices).
### Vue and Vuex
Test as much as possible without double-testing Vue's internal features, as mentioned above.
Make sure to test computedProperties, mutations, actions. Run the action and test that the proper mutations are committed.
Also check these [notes on testing Vue components](../../fe_guide/vue.html#testing-vue-components).
#### Vuex Helper: `testAction`
We have a helper available to make testing actions easier, as per [official documentation](https://vuex.vuejs.org/en/testing.html):
