Cannot read property 'thisCompilation' of undefined during npm run build

I’ve been running react-scripts build in docker for last 3 months and suddenly our builds started failing this week (without any change in the package.json dependencies)

Is this a bug report?

Yes

Did you try recovering your dependencies?

Yes, using nvm with node 6.11.1 and npm 3.10.10

Which terms did you search for in User Guide?

using npm run build, not using anythin relevant

Environment

1. node -v: 6.11.1
2. npm -v: 3.10.10
3. yarn --version (if you use Yarn): N/A
4. npm ls react-scripts (if you haven’t ejected):

Then, specify:

1. Operating system: Debian 9.3 (Docker nginx:1.13)
2. Browser and version (if relevant): N/A

Steps to Reproduce

apt-get -y update apt-get -y install curl apt-get -y install gnupg apt-get -y install gnupg1 gnupg2 procps curl -sL https://deb.nodesource.com/setup_6.x | bash - apt-get -y install nodejs curl https://raw.githubusercontent.com/creationix/nvm/v0.33.0/install.sh | bash - source ~/.nvm/nvm.sh nvm list nvm install v6.11.1 npm install npm rebuild node-sass --force CI=“” npm run build

Expected Behavior

Creating an optimized production build… File sizes after gzip:

341.23 KB build/static/js/main.0a9ca280.js 35.24 KB build/static/css/main.7b053899.css …

Actual Behavior

Creating an optimized production build… Failed to compile.

Cannot read property ‘thisCompilation’ of undefined

npm ERR! Linux 4.9.60-linuxkit-aufs

…

npm-debug.log

Reproducible Demo

TBD - will try to create a docker with mock project.

[gaearon]

I’m going to close because there were no reproducible examples shared.

To solve this problem:

• Delete node_modules
• Delete package-lock.json if present
• If you have react-scripts in package.json, make sure you don’t have webpack in it
• Run yarn (or npm install)
• Also make sure you don’t have package.json or node_modules in the parent folders of your project

[NickFoden]

TLDR: Error " Cannot read property ‘thisCompilation’ of undefined " in our React app (CRA initialization)- was additional install of dependency of webpack. Remove node_modules. Remove webpack in package.json. Yarn install. Good to go.

After npm run start was unable to compile. I had the error “Cannot read property ‘thisCompilation’ of undefined” within React app created with Create React App and error code ELIFECYCLE part of log here: error code ELIFECYCLE 21 error errno 1 22 error icon@0.1.0 start: react-scripts start 22 error Exit status 1 23 error Failed at the icon@0.1.0 start script. 23 error This is probably not a problem with npm. There is likely additional logging output above. 24 verbose exit [ 1, true ]

At first thought it was older semantic-ui running gulp-util but then we had “webpack” installed as a dependency in the package.json, which I believe after comparing to other repos built with CRA, is unnecessary dependency. 1. Removed node-modules and lockfiles and the “webpack” dependency. 2. Yarn install. 3. And npm run start no problem now.