Handlebars helper for state

[richardruiter]

We have BDD scenarios that often change (a small) part of the mocks. We don't want to copy a mock fle just because one boolean changed for example nor do we want all kind of complex conditionals etc.

Therefor we have created a custom handlebar helper called "state" and it get's it's value from a cookie, because that's most easy to configure from a client side.

This is the helper so far

[
    {
        "name": "state",
        "logic": "(()=>{ return require(process.cwd() + '/src/helpers/state.js')(this, context); })()"
    }
]

/**
State helper

This helper gets the mocked state value using a key send within the cookie header.
If no value is found it will use the default context within the block.

For example:
``json
{
    "has_pending_order": {{#state key='has-pending-order'}}false{{/state}}
}
``

To set a value just send cookie with a specific prefix .

``js
const prefix = "mocked-state";
const key = "has-pending-order";
setCookie(`${prefix}-${key}`, "true");
``

WARNING: the limit of cookie values in most browsers is 4KB 
**/

module.exports = function(self, context) {
    const cookie = context.data.root.request.headers.cookie;
    const key = context.hash.key;
    const value = new RegExp(`mocked-state-${key}=([^;]+)`).exec(cookie);
    return value ? value[1] : context.fn(self);
};

From the test runner (in our case Cypress) we can just set the state for the session using a cookie.
The biggest advantage of this is that we can run tests in parallel without thinking about it.

/**
 * Custom cypress command to set a mocked state
 */
Cypress.Commands.add('setState', (key: string, value: unknown) => {
    cy.setCookie(`mocked-state-${key}`, typeof value === 'string' ? value : JSON.stringify(value));
});

Given('There is no pending order for my account', () => {
    cy.setState('has_pending_order', false);
});

Given('There is a pending order for my account', () => {
    cy.setState('has_pending_order', true);
});

How about adding this to the default helpers? Do you like the name? etc.

[richardruiter]

Already made a PR :)