Class constructor FileManager cannot be invoked without 'new'.

[micooz]

It seems that v3.10.0 breaks my build, webpack logs below:

ERROR in ./src/pages/score/components/current/no-join/index.less
Module build failed (from ./node_modules/_mini-css-extract-plugin@0.5.0@mini-css-extract-plugin/dist/loader.js):
ModuleBuildError: Module build failed (from ./node_modules/_less-loader@4.1.0@less-loader/dist/cjs.js):


Class constructor FileManager cannot be invoked without 'new'
      in undefined (line undefined, column undefined)
    at runLoaders (/home/admin/build/node_modules/_webpack@4.39.2@webpack/lib/NormalModule.js:313:20)
    at /home/admin/build/node_modules/_loader-runner@2.4.0@loader-runner/lib/LoaderRunner.js:367:11
    at /home/admin/build/node_modules/_loader-runner@2.4.0@loader-runner/lib/LoaderRunner.js:233:18
    at context.callback (/home/admin/build/node_modules/_loader-runner@2.4.0@loader-runner/lib/LoaderRunner.js:111:13)

Everything is ok when downgrade to v3.9.0, please investigate this issue and hope to fix it as soon as possible.

[xiaoningzihai]

I have the same problem，you mast change you 'package.json' => "less": "~3.9.0", limit version

[here-we-goal]

+1

[AlwaysSkylll]

+1

[lzf0402]

+1!
急 ～

[Liqihan]

+1

[yolo2013]

same problem

[Doneitha]

+1 version less 3.9.0 less-loader 4.1.0

[Doneitha]

可以把package.json中 less版本的 ^ 去掉 重新安装一下 v3.9.0 应该就可以解决问题 大家可以试一下
虽然 锁定了版本 但是由于 ^, 所以会下载3 一下的最新版本， 最新版本应该是有问题的。

[lizux]

+1

[wangmingquan]

+1

[AlwaysSkylll]

const shortname = new this.less.FileManager().extractUrlParts(filename).filename;

这个类似代码引起的？

[Tindtily]

omg， i limited the version to 3.9.0，works.

[starzle]

Same here. npm picks up this "minor" release automatically, and breaks all of my builds. :(

[huxiaoqi567]

+1

[smackgg]

v3.10.0 same error

[AlixWang]

+1

[doxiaodong]

hurry

[simple7]

+1

[lixiaohulee]

just use less-loader@5.0.0 every thing will be ok

[0x80]

@lixiaohulee unless you're not using less-loader and everything will not be ok

[wangsanshao]

+1

[asiareal]

+1

[KatDenisenko]

I have the same problem (((

[Lalitha-Iyer]

+1

[kikeztw]

i have the same problem :/

[matthew-dean]

This is an issue with an older version of less-loader, not Less, which did not inherit the Less filemanager correctly. less-loader 5.0 does. See: #3414 (comment)

[matthew-dean]

Can someone try: #3421?

Branch is at: https://github.com/matthew-dean/less.js/tree/release/v3.10.2

The challenge in testing this is that less-loader's own tests fail on 3.9.0, so it's not clear what's expected. But, with Less's exported classes transpiled down to functions, the same errors at least get triggered in less-loader, so it's not clear if that's expected output or not. It's also not clear how or why this error occurs in Less loader v4, and doesn't occur in v5, except it may be a Webpack issue on v4?

In any case, if people can confirm that this branch as a Less dependency doesn't cause the class issue, then I'll merge it in.

[wantwant123]

+1 version less 3.9.0 less-loader 4.1.0

[MustafinVadim]

+1

[huangrx-cn]

+1

[lang1427]

Manually specify less version ：
npm i less@3.9.0 -D
ok!!!

[JunlinZhu-Tommy]

Fix by downgrade to 3.9.0

[vipcxj]

Just before, I delete the node_modules and type npm i, this error happen. So the latest version 3.10.1 still has this bug. I choose downgrade to 3.9.0

[ezgitek]

How would I fix this bug if I am using @zeit/next-less? Any help appreciated.

[hua1995116]

@ezgitek

npm i @zeit/next-less
npm i less@3.9.0

[buerxixi]

https://forum.vuejs.org/t/vue-cli/72008/7
"less": "^3.10.1",
"less-loader": "^5.0.0",
is running

[matthew-dean]

Merged: #3421

No one with less-loader v4 issues seemed willing to test [3.10.2] 🤷‍♂, but in my testing, Less-loader's v4 tests broke differently with 3.10.1 (class constructor issue), and broke the same with this PR. So..... not sure if it fixes it, but it should be no worse?

I merged that possible fix into master (but not yet released to NPM). Still would love for someone to confirm before releasing instead of the +1's.

[jenniferneale]

I can confirm I just tried the current master branch of less locally with less-loader ^4.1.0, and my project is able to build again. 👍

[jenniferneale]

Thanks for your work on this!

[matthew-dean]

@jenniferneale Thanks for confirming! I'll publish to NPM later today then, can't do it from work.

[pod4g]

+1

[hungmanle]

Is this issue fixed with 3.10.3?

[matthew-dean]

@h4ngman Should be. Re-open if not.