npm install won't install devDependencies

问题:

On windows for some reason when I run npm install it won't install devDependencies. AFAIK it should. If I run npm install --dev devDependencies are installed. I don't understand why npm install doesn't install devDependencies too, but installs only dependencies. What could be the reason? How can I fix it? Maybe smth is wrong with my package.json? It is listed below if it may be helpful

{
  "name": "try-brunch",
  "version": "0.1.0",
  "private": "true",
  "devDependencies": {
    "brunch": "^2.0.4",
    "cssnano-brunch": "^1.1.5",
    "javascript-brunch": "^1.8.0",
    "sass-brunch": "^1.9.2",
    "uglify-js-brunch": "^1.7.8"
  },
  "dependencies": {
    "jquery": "^2.1.4"
  }
}

回答1:

Check the NPM docs for install

With the --production flag (or when the NODE_ENV environment variable is set to production), npm will not install modules listed in devDependencies."

The --only={prod[uction]|dev[elopment]} argument will cause either only devDependencies or only non-devDependencies to be installed regardless of the NODE_ENV."

Have you tried

npm install --only=dev

If you are worried that your package.json might be incorrect, best thing to do is this. Create a new folder, and run:

npm init --yes

Then:

npm install --save-dev brunch@^2.0.4
npm install --save-dev cssnano-brunch@^1.1.5
npm install --save-dev javascript-brunch@^1.8.0
npm install --save-dev sass-brunch@^1.9.2
npm install --save-dev uglify-js-brunch@^1.7.8
npm install jquery@^2.1.4 --save

And you should be good to go! Otherwise, will keep posting other options.

Check your npm configuration:

npm config list

npm gets its config settings from the command line, environment variables, and npmrc files. So check environment variables, and the npmrc file.

Still failing?

Ok, create a new folder, ideally somewhere else on your filesystem. ie. not in same folder hierarchy. For instance, C:\myNewFolder - the closer to the base C: drive the better.

Then run:

npm init --yes

Now run:

npm install underscore --save

and finally:

npm install mocha --save-dev

Does everything work as expected?

What I am trying to do is understand whether your problem is global, or something local to the previous folder and dependencies.

回答2:

Check if npm config production value is set to true. If this value is true, it will skip over the dev dependencies.

Run npm config get production

To set it: npm config set -g production false

回答3:

make sure you don't have env variable NODE_ENV set to 'production'.

If you do, dev dependencies will not be installed without the --dev flag

回答4:

I had a package-lock.json file from an old version of my package.json, I deleted that and then everything installed correctly.

回答5:

I had a similar problem. npm install --only=dev didn't work, and neither did npm rebuild. Ultimately, I had to delete node_modules and package-lock.json and run npm install again. That fixed it for me.

回答6:

Make sure your package.json is valid...

I had the following error...

npm WARN Invalid name: "blah blah blah"

and that, similarly, caused devDependencies not to be installed.

FYI, changing the package.json "name" to blah-blah-blah fixed it.

回答7:

You can use the short way for installation dependencies only for development as follows:

npm i -D <dependencies-names>