Fix MDXContent to allow missing props

[mike-mcdonald]

Adjusts MDXContent function output to allow undefined props as a parameter without throwing a TypeError.

Closes #82

[wooorm]

Sweet, thanks for working on this!

I think it would be better to solve it in the argument list: MDXContent(props = {}).
Reasoning is that it’s documented that props is an object in one example of the readme: https://github.com/wooorm/xdm#mdx-content.

Also, could you update the example in the readme following “The actual output of running node example.js is:”?

There are also two errors in the tests on CI. the babel one looks a bit flakey (I’ll check if that’s still the case), but the error message might need to be changed?

[wooorm]

ps. run npm test locally to test your changes! And you can use ASTExplorer to figure out what the AST is for certain JS code

[wooorm]

Rebasing your PR against main should solve the weird babel error

[wooorm]

The other error was related due to a change in Node 16.9. Updates the tests to fix that as well.

[mike-mcdonald]

@wooorm Sounds like a plan. I'll adjust the fix to provide a default value for the props parameter and work on the test errors.

[mike-mcdonald]

@wooorm I've updated my branch with your changes to main and am able to run npm run test locally with no failures now!

[wooorm]

Thanks, released!