TypeError: this.getPosition is not a function in LessParser.inlineComment

[PlayApple]

TypeError: this.getPosition is not a function

"lint:style": "stylelint --fix "src/**/*.less" --custom-syntax postcss-less"

TypeError: this.getPosition is not a function
at LessParser.inlineComment (/web/node_modules/postcss-less/lib/LessParser.js:71:28)
at LessParser.isInlineComment (/web/node_modules/postcss-less/lib/nodes/inline-comment.js:37:12)
at LessParser.other (/web/node_modules/postcss-less/lib/LessParser.js:156:36)
at LessParser.parse (/web/node_modules/postcss/lib/parser.js:75:16)
at parse (/web/node_modules/postcss-less/lib/index.js:11:12)
at new LazyResult (/web/node_modules/stylelint/node_modules/postcss/lib/lazy-result.js:133:16)
at getPostcssResult (/web/node_modules/stylelint/lib/getPostcssResult.js:77:30)
at async lintSource (/web/node_modules/stylelint/lib/lintSource.js:76:4)
at async /web/node_modules/stylelint/lib/standalone.js:218:27
at async Promise.all (index 0)

How can i fixed it. Thanks.

[ybiquitous]

@PlayApple Can you reproduce the error on the demo?

Also, please use the issue template for a bug report.

[strigefleur]

@PlayApple you probably forgot to install postcss itself.
I believe postcss-less not gonna work without it.

[PlayApple]

Sorry , i upload the demo project.

myapp.zip

`yarn lint
yarn run v1.22.15
$ umi g tmp && npm run lint:js && npm run lint:style && npm run lint:prettier && npm run tsc
Browserslist: caniuse-lite is outdated. Please run:
npx browserslist@latest --update-db

Why you should do it regularly:
https://github.com/browserslist/browserslist#browsers-data-updating

ant-design-pro@5.0.0 lint:js /demo/myapp
eslint --cache --ext .js,.jsx,.ts,.tsx --format=pretty ./src

ant-design-pro@5.0.0 lint:style /demo/myapp
stylelint --fix "src/**/*.less" --custom-syntax postcss-less

TypeError: this.getPosition is not a function
at LessParser.inlineComment (/demo/myapp/node_modules/postcss-less/lib/LessParser.js:71:28)
at LessParser.isInlineComment (/demo/myapp/node_modules/postcss-less/lib/nodes/inline-comment.js:37:12)
at LessParser.other (/demo/myapp/node_modules/postcss-less/lib/LessParser.js:156:36)
at LessParser.parse (/demo/myapp/node_modules/postcss/lib/parser.js:75:16)
at parse (/demo/myapp/node_modules/postcss-less/lib/index.js:11:12)
at new LazyResult (/demo/myapp/node_modules/stylelint/node_modules/postcss/lib/lazy-result.js:133:16)
at getPostcssResult (/demo/myapp/node_modules/stylelint/lib/getPostcssResult.js:77:30)
at async lintSource (/demo/myapp/node_modules/stylelint/lib/lintSource.js:76:4)
at async /demo/myapp/node_modules/stylelint/lib/standalone.js:218:27
at async Promise.all (index 0)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! ant-design-pro@5.0.0 lint:style: stylelint --fix "src/**/*.less" --custom-syntax postcss-less
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the ant-design-pro@5.0.0 lint:style script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /Users/liuyanghui/.npm/_logs/2021-10-28T13_45_03_497Z-debug.log
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.`

[alexander-akait]

Run npm ls postcss-less

[PlayApple]

yarn install
yarn lint Will go wrong

[alexander-akait]

Please run command above

[PlayApple]

[lachieh]

Can you do the same with npm ls postcss?

It seems like postcss-less depends on postcss@8, but doesn't has it listed in devDependencies which might be preventing it from adding the dependency? Anyone have any more insight into how npm/yarn handles deduping devDependencies? I think maybe postcss-less needs to add postcss@8 as a peer dependency?

Running yarn add postcss@8 fixes the issue, but it probably shouldn't be the permanent fix.

[ybiquitous]

@PlayApple Your project's postcss version seems outdated.

$ node -pe 'require("postcss/package.json").version'
7.0.39

postcss-less@5.0.0 requires postcss@8. See below:
https://github.com/shellscape/postcss-less/blob/v5.0.0/package.json#L44

[PlayApple]

npm ls postcss

[lachieh]

@PlayApple run this:
yarn add postcss@8

[zheeeng]

@lachieh @alexander-akait I'm using PNPM and encountered the same problem.

pnpm ls postcss-less

devDependencies:
postcss-less 5.0.0

pnpm ls postcss

devDependencies:
postcss 8.3.11

[NansD]

I have the same issue with

└─ postcss-less@5.0.0

and

│  └─ postcss@8.4.4
├─ postcss-safe-parser@5.0.2
│  └─ postcss@8.4.4
├─ postcss@7.0.39
├─ resolve-url-loader@3.1.4
│  └─ postcss@7.0.36
└─ stylelint@14.1.0
   └─ postcss@8.4.4

is there something I'm doing wrong ?

[ybiquitous]

@NansD Can you provide your .stylelintrc file, please? I'm curious where customSyntax: 'postcss-less' is.

EDIT: Please see also #5632 (comment)

[NansD]

Thank you for your help !

my .stylelintrc.json was like this :

{
  "extends": "stylelint-config-standard",
  "customSyntax": "postcss-less"
}

And I just tried transforming it to a js file like so :

module.exports = {
  "extends": "stylelint-config-standard",
  "customSyntax": require("postcss-less")
}

but still get TypeError: this.getPosition is not a function

[cong1223]

if you use less , these deps you have to install :
"postcss": "8", "postcss-less": "^6.0.0", "stylelint": "^14.5.1", "stylelint-config-recommended-less": "^1.0.4",

[NansD]

It works, thank you!