How to test schema defaults for a Gatsby Plugins

The recommended way to test your pluginSchemaOption function is to use testPluginOptionsSchema from the gatsby-plugin-utils package.

For information on how to get started with plugin testing and how to use the testPluginOptionsSchema, read Add tests to your Gatsby Plugin project ✅ 🧪.

However, when writing tests for the gatsby-plugin-cloudinary plugin this week, I realized it does not help with testing the default configuration or any other modifiers.

Luckily testing the pluginSchemaOption without the help of testPluginOptionsSchema was possible:

import Joi from "joi";
import { pluginOptionsSchema } from "./gatsby-node";

describe("pluginOptionsSchema", () => {
  test("should add defaults", async () => {
    const schema = pluginOptionsSchema({ Joi });
    const options = {
      cloudName: "cloudName",
      apiKey: "apiKey",
      apiSecret: "apiSecret",
      maxResults: 50,
    };
    const { value } = schema.validate(options);

    expect(value).toEqual({
      ...options,
      resourceType: "image",
      maxResults: 50,
      resultsPerPage: 50,
      tags: false,
    });
  });
});

It was extra important for this plugin as resultsPerPageis actually dependent on maxResults using Joi.ref('maxResults').

Let me know if this was of use to you!

All the best,
Queen Raae

PS: Tomorrow, we'll get a sneak peek at the almost fully cooked Gatsby Slices API 🍕