[BUG] npm 7.x executes package.json preinstall script after installing dependencies

[Ngorror]

Current Behavior:

when you run npm install, package.json preinstall script will be executed after dependencies installation

Expected Behavior:

package.json preinstall script must be executed before dependencies installation.

Steps To Reproduce:

Execute the following commands to clone my test repository and run npm install to reproduce the problem

git clone https://github.com/Ngorror/npm-preinstall-bug.git
cd npm-preinstall-bug
npm install

OR

1. create package.json file in empty directory with the following content:

{
  "name": "npm-preinstall-bug",
  "version": "1.0.0",
  "dependencies": {
    "mongodb": ">=3.6.0"
  },
  "description": "",
  "main": "index.js",
  "scripts": {
    "preinstall": "rm -f -R node_modules"
  },
  "author": "",
  "license": "ISC"
}

2. execute npm install
3. npm will install dependencies and then it will execute preinstall script. as result node_modules directory will be deleted.

Environment:

• OS: Linux Mint 20.04, Windows 10
• Node: >=17.0.0
• npm: >= 7.0.2

[ljharb]

Can you confirm the bug still happens in v7.0.15?

[Ngorror]

yep
I stumbled on this on my first install of node 15.0.0, npm 7.0.2 few months ago.
Since then I procrastinated to report the problem.
yesterday I installed node 15.3.0, npm 7.0.14
now I installed 7.0.15 - the problem is still here.

[darcyclarke]

@Ngorror this is actually working as intended; If, as your example alludes, you want to do a clean install - you can/should use npm ci

[pmunin]

Can someone reopen this issue? preinstall still not running before dependencies installation

[bugsounet]

Not always fixed ? (and same bug in v8)