False Positive in PostCSS Config file: postcss.config.js

[deadcoder0904]

Bug Description

Gives false positive in PostCSS Config file.

Code snippets

I have the following postcss.config.js:

module.exports = {
	plugins: [
		'postcss-import',
		'tailwindcss',
		'postcss-flexbugs-fixes',
		[
			'postcss-preset-env',
			{
				autoprefixer: {
					flexbox: 'no-2009',
				},
				stage: 3,
				features: {
					'custom-properties': false,
				},
			},
		],
	],
}

The above syntax is for using PostCSS in combo with Next.js.

It's a little different syntax from the original postcss.config.js file. The original syntax uses require like:

module.exports = {
	plugins: [
		require('postcss-import'),
		require('tailwindcss'),
		require('postcss-flexbugs-fixes'),
		[
			require('postcss-preset-env'),
			{
				autoprefixer: {
					flexbox: 'no-2009',
				},
				stage: 3,
				features: {
					'custom-properties': false,
				},
			},
		],
	],
}

Where the dependency is listed in package.json:

{
	"dependencies": {
		"@mapbox/rehype-prism": "^0.5.0",
		"@mdx-js/react": "^1.6.19",
		"@types/nprogress": "^0.2.0",
		"fast-glob": "^3.2.4",
		"next": "10.0.1",
		"nprogress": "^0.2.0",
		"react": "^17.0.1",
		"react-dom": "^17.0.1",
		"tinytime": "^0.2.6",
		"unist-util-visit": "^2.0.3"
	},
	"devDependencies": {
		"@mdx-js/loader": "^1.6.19",
		"@next/bundle-analyzer": "^10.0.1",
		"@types/mdx-js__react": "^1.5.3",
		"@types/node": "^14.14.6",
		"@types/react": "^16.9.55",
		"@types/react-dom": "^16.9.9",
		"@types/webpack-env": "^1.15.3",
		"cross-env": "^7.0.2",
		"feed": "^4.2.1",
		"file-loader": "^6.2.0",
		"postcss-flexbugs-fixes": "^5.0.0",
		"postcss-import": "^13.0.0",
		"postcss-preset-env": "^6.7.0",
		"rimraf": "^3.0.2",
		"simple-functional-loader": "^1.2.1",
		"tailwindcss": "^1.9.6",
		"typescript": "4.0.5"
	},
	"license": "ISC"
}

Versions

• node -v: v15.1.0
• npm -v: 7.0.8
• depcheck --version: 1.2.0

When I use depcheck it gives:

➜ depcheck         
Unused devDependencies
* @mdx-js/loader
* @types/react-dom
* @types/webpack-env
* postcss-flexbugs-fixes
* postcss-import
* postcss-preset-env

For cloning, just clone https://github.com/tailwindlabs/blog.tailwindcss.com & paste the above postcss.config.js as is (the one without the require syntax).

I've filed @mdx-js/loader issue which you've probably resolved, I haven't checked yet → #583

@types/react-dom & @types/webpack-env are used for TS but aren't included anywhere. Not sure if this issue is similar to #582

The last 3 starting with postcss-* are the bugs of this issue I think.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[karlhorky]

Is this actually stale? Or is this still an issue? I don't see a postcss.js file in the special folder

cc @rumpl

[rumpl]

It's stale in a sense that no one is working on it for a long time so the bot closes it

[karlhorky]

Ok no worries, should a new issue be opened? Or can this one be reopened?