[!] (plugin postcss) Error: PostCSS plugin autoprefixer requires PostCSS 8.

[vaseala]

It report:
[!] (plugin postcss) Error: PostCSS plugin autoprefixer requires PostCSS 8. when I use autoprefixer@10.0.1

[boguz]

i am also getting the same error "requires PostCSS 8" error while using:

• "rollup": "^2.3.4",
• "postcss-import": "^13.0.0",
• "rollup-plugin-postcss": "^3.1.8",
• "rollup-plugin-postcss-lit": "^1.0.1"

And this is the error: [!] (plugin postcss) Error: PostCSS plugin postcss-import requires PostCSS 8.

[isaacl]

That's because postcss 7 is listed as a dependency here, when it should be a peerDependency.

And as far as I can tell, this project only supports postcss 7 at the moment.

[eugeneilyin]

@egoist, @benmccann, @MichaelAnd, @wardpeet, @JounQin can you fix this peerDependency in the package.json for rollup-plugin-postcss from the suggested fork in #324 and put it into npm? It's very annoying to revert package.json manually to the fixed variant after any yarn command due to npm contains the 3.1.8 version. Thanks :)

{
  "name": "rollup-plugin-postcss",
  "version": "3.1.9",
  "description": "Seamless integration between Rollup and PostCSS",
  "main": "dist/index.js",
  "files": [
    "dist",
    "types/index.d.ts"
  ],
  "scripts": {
    "test": "npm run lint && jest",
    "test:cov": "npm run lint && jest --coverage",
    "build": "bili",
    "lint": "xo",
    "prepublishOnly": "npm run build"
  },
  "repository": {
    "type": "git",
    "url": "git+https://github.com/egoist/rollup-plugin-postcss.git"
  },
  "keywords": [
    "postcss",
    "rollup"
  ],
  "author": "EGOIST <0x142857@gmail.com>",
  "license": "MIT",
  "bugs": {
    "url": "https://github.com/egoist/rollup-plugin-postcss/issues"
  },
  "engines": {
    "node": ">=10"
  },
  "types": "./types/index.d.ts",
  "homepage": "https://github.com/egoist/rollup-plugin-postcss#readme",
  "devDependencies": {
    "@babel/core": "^7.9.0",
    "@babel/preset-env": "^7.9.5",
    "autoprefixer": "^10.0.1",
    "babel-core": "^7.0.0-bridge.0",
    "babel-jest": "^26.6.3",
    "bili": "^5.0.5",
    "eslint-config-rem": "^4.0.0",
    "fs-extra": "^9.0.0",
    "jest": "^26.6.3",
    "less": "^3.11.1",
    "node-sass": "^4.13.1",
    "postcss": "^8.1.6",
    "rollup": "^2.6.1",
    "stylus": "^0.54.7",
    "sugarss": "^3.0.3",
    "xo": "^0.29.1"
  },
  "dependencies": {
    "chalk": "^4.0.0",
    "concat-with-sourcemaps": "^1.1.0",
    "cssnano": "^4.1.10",
    "import-cwd": "^3.0.0",
    "p-queue": "^6.3.0",
    "pify": "^5.0.0",
    "postcss-load-config": "^3.0.0",
    "postcss-modules": "^3.2.2",
    "promise.series": "^0.2.0",
    "resolve": "^1.16.1",
    "rollup-pluginutils": "^2.8.2",
    "safe-identifier": "^0.4.1",
    "style-inject": "^0.3.0"
  },
  "peerDependencies": {
    "postcss": "^8.1.6"
  },
  "xo": {
    "extends": "rem",
    "envs": [
      "jest"
    ],
    "rules": {
      "import/prefer-default-export": 0,
      "import/extensions": 0,
      "import/no-unassigned-import": 0,
      "@typescript-eslint/semi": 0,
      "eslint-comments/disable-enable-pair": 0,
      "promise/prefer-await-to-then": 0
    }
  },
  "jest": {
    "testEnvironment": "node"
  },
  "babel": {
    "presets": [
      [
        "@babel/preset-env",
        {
          "targets": {
            "node": "6"
          }
        }
      ]
    ]
  },
  "release": {
    "branches": [
      "master",
      "next"
    ]
  }
}

[SASUKE40]

🎉 This issue is resolved in version 4.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

[ycg520520]

最新版本还是会报错具体原因是：cssnano的版本问题，在项目中配置
"peerDependencies": {
"cssnano": "^5.0.3"
}