Use JSON5 For package.json

[machineghost]

JSON5 ("JSON for Humans"), includes features such as comments, which have long been desired in package.json.

If package.json adopted JSON5 it would add not only comments, but also a number of minor conveniences (eg. optional trailing commas, optional key quoting, single-quoted strings, etc. ... all just like in JS!) And switching to the new standard would be incredibly simple.

See https://json5.org/ for more info.

[ljharb]

.json means JSON. JSON5 would necessitate a different extension.

Also, supporting JSON5 in package.json would break every app that passes package.json's contents through JSON.parse, indirectly or directly.

[remyrylan]

I think that ship sailed a long time ago. There are thousands of packages in the npm registry that expect to require or use JSON.parse for package.json. Changing to a new format would break every single one of them.

I know JSON5/JSON-C (JSON w/ comments) is gaining traction, with more tools supporting it. Still, those tools usually support it from their inception, so the supporting ecosystem is built around the requirement to parse the .json configs differently. TypeScript, as an example, ships with a config file parser, so you don't even have to use json5 if you already have typescript installed.

But for package.json -- the negative impact would be too high. Best to leave as-is.

[ljharb]

The first step would be landing a native stringify/parse pair for JSON5 in node. A stronger path to that than just trying to land it there would be to try to standardize it in WinterCG; stronger than that, in browsers; and even stronger still, in the JS language.

Once that functionality was shipping in all actively supported node versions, then tooling can begin to support the format. At the same time, it would start to become reasonable for npm to explore shipping the requested functionality in some form.

In other words, it's a many year journey, involving many stakeholders and lots of compelling evidence and persuasion - but unfortunately so far nobody's been willing to put in more effort than typing up github comments, so the journey still hasn't yet begun.

[evert]

All change has to start somewhere though =). I think we can be forgiven for sharing a desire for this in the appropriate channels. I don't understand all the negativity in every comment, but maybe that's a lost in translation thing.

[wesleytodd]

Yeah I think it is just a mis-understanding of the tone. @ljharb is deeply involved in the ecosystem, specification work, and some very popular tools. I would recommend you take his responses here more as "recognization of how hard this reality can be" than "negativity".

I think a reasonable middle ground might be for someone to try and push for Node.js to vendor in a user land JSON5 parser as experimental. And then from that land experimental support for Node.js to use that file for things like exports. If someone wants to start that work then I think it would really help prove out this for npm to then consider it.

[evert]

Thanks, that. Sounds like a really solid first step!

[evert]

Looks like a lot of discussion has already happened here, and it's unfortunately closed:

nodejs/node#40714

Interesting point is that pnpm does support json5.

[evert]

At the very least it would be possible to write .json files in when building npm packages and when installing in node_modules, but (optionally) support JSON5 at the top-level. Yes this will break some tools but it's an opt-in change and tooling will catch up.