Why is my NPM cache folder in ./false/_cacache?

Question

I am on an NPM project using Docker, PhpStorm, VS Code and runs locally and through Docker.

Under which circumstances is this folder put into ./false/? Has anyone encountered this in the past and would share what they found out?

project-root-dir
|__ false
   |__ _cacache
      |__ <hash>
|__ node_modules
|__ Dockerfile
|__ main.js
|__ package.json

I suspect this line is creating the folder _cacache folder inside false:

FROM node:12

# ...

# Some directory is missing at this point and results in `false` ?
RUN npm install -g npm

Answer 1

This is because the NPM configuration for cache has been set to false somewhere. You might expect that to disable caching, but cache is expecting a string, the path to the cache directory.

In this case it's because you ran with --no-cache; anything you pass as --no-<name> sets the config of <name> to false.