@@ -1081,55 +1081,6 @@ If you use the RubyMine IDE, and have marked the `tmp` directory as
`gitlab/tmp/tests/graphql`. This will allow the **JS GraphQL** plugin to
automatically find and index the schema.
#### Mocking response as component data
<!-- vale gitlab.Spelling = NO -->
With [Vue Test Utils](https://vue-test-utils.vuejs.org/) one can quickly test components that
fetch GraphQL queries. The simplest way is to use `shallowMount` and then set
the data on the component:
<!-- vale gitlab.Spelling = YES -->
```javascript
it('tests apollo component',()=>{
constvm=shallowMount(App);
vm.setData({
...mockData
});
});
```
#### Testing loading state
To test how a component renders when results from the GraphQL API are still loading, mock a loading state into respective Apollo queries/mutations:
```javascript
functioncreateComponent({
loading=false,
}={}){
const$apollo={
queries:{
designs:{
loading,
},
},
};
wrapper=shallowMount(Index,{
sync:false,
mocks:{$apollo}
});
}
it('renders loading icon',()=>{
createComponent({loading:true});
expect(wrapper.element).toMatchSnapshot();
})
```
#### Testing Apollo components
If we use `ApolloQuery` or `ApolloMutation` in our components, in order to test their functionality we need to add a stub first:
...
...
@@ -1197,11 +1148,9 @@ it('calls mutation on submitting form ', () => {
});
```
### Testing with mocked Apollo Client
To test the logic of Apollo cache updates, we might want to mock an Apollo Client in our unit tests. We use [`mock-apollo-client`](https://www.npmjs.com/package/mock-apollo-client) library to mock Apollo client and [`createMockApollo` helper](https://gitlab.com/gitlab-org/gitlab/-/blob/master/spec/frontend/__helpers__/mock_apollo_helper.js) we created on top of it.
#### Mocking Apollo Client
To separate tests with mocked client from 'usual' unit tests, create an additional factory and pass the created `mockApollo` as an option to the `createComponent`-factory. This way we only create Apollo Client instance when it's necessary.
To test the components with Apollo operations, we need to mock an Apollo Client in our unit tests. We use [`mock-apollo-client`](https://www.npmjs.com/package/mock-apollo-client) library to mock Apollo client and [`createMockApollo` helper](https://gitlab.com/gitlab-org/gitlab/-/blob/master/spec/frontend/__helpers__/mock_apollo_helper.js) we created on top of it.
We need to inject `VueApollo` into the Vue instance by calling `Vue.use(VueApollo)`. This will install `VueApollo` globally for all the tests in the file. It is recommended to call `Vue.use(VueApollo)` just after the imports.
