Provide a method to retrieve parameters in the API hooks

[shilman]

Currently there is no stylized way to retrieve story parameters in API hooks.

This would be useful for reusing:

• viewports configurations
• a11y parameters
• etc.

This could be provided automatically by the test-runner as part of the context argument.

  async preRender(page, context) {
    const { parameters } = context;
  },

Or maybe on=demand:

  async preRender(page, context) {
    const parameters = await getParameters(page, context);
    // OR
    const parameters = await context.getParameters(page);
  },

The benefit of on-demand is that the user would only "pay" the performance cost of retrieving parameters when they are actually used.

[lacolaco]

I strongly want parameters for viewports configurations and skipping screenshots for some stories!

[jakubriedl]

This is super important for accessibility testing, but in principle for any configuration of tests.

in the meantime I workaround this by saving story props to window in decorator and reading it back in the test

preview.tsx

export const decorators: DecoratorFn[]= [
  (Story, props) => {
    window.STORY_PROPS = props
    return <Story {...props} />
  },
]

test-runner.ts

export const postRender: TestHook = async (page, context) => {
  const { parameters }: any = await page.evaluate("window.STORY_PROPS")
  // ...
}

[yannbf]

Hey peeps! This was released in v0.2.0, please check the details here. Thanks for using this library!