docs for developers: expected JS code style

[danielfdickinson]

How can we otherwise help?

I noticed there is a JS/JSON CodeQL GitHub action and use, and am wondering what the expectations are for code style (so as not to run afoul of the checks when submitting an app).

I did some poking about and didn't find any notes on that in README or Wiki.

[systemcrash]

Hard to codify - but tabs over spaces, and the JSON check is to verify validity. ES6.

[efahl]

I'd also be interested in linting tool recommendations, preferably CLI-based. I hadn't done any js work since early 2000s until recently, and just guessing from reading through code and PRs is less than optimal.

[danielfdickinson]

@efahl I found eslint with a configuration such as https://github.com/openwrt/luci/pull/8216/files#diff-c80b39893de8a7efe4a6c873867202f7cb64ae799b9c2d32e8d53cdc6e931ad2 helped me. Depends on whether you are adverse to Node.js tools for your CLI tools.

eslint can be used as a command line tool, or from within an editor that uses the command line internally to present feedback in the editor.

It seems to have been compatible with the repository's CodeQL setup.

[danielfdickinson]

@efahl Here is a better link (actual file instead of diff) with some additions based on @systemcrash's review of my PR for radicale3 (#8216): https://gitlab.com/dfd-web/firmware/openwrt-luci/-/blob/pr-add-radicale3-with-passlib/applications/luci-app-radicale3/eslint.config.mjs

[systemcrash]

What is a dangling comma?

This is OK and recommended:

const object = {
 foo: 1,
 bar: 2,
}

since it has the benefit that git changes and diffs easier to read when you're just adding or removing lines.

[danielfdickinson]

Ok. Will update.

[danielfdickinson]

On the ES6 front: would arrow functions ( (var) => { } ) be preferred, or the traditional function (function () { }) for callbacks and such?

[systemcrash]

arrow. shorter. cleaner. Has some benefits which I forget :)