how to run node / babel script directly in command line?

Question

My package.json looks like:

{
  "name": "99-nodetest",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "babel-node --presets env app.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "babel-cli": "^6.26.0",
    "babel-preset-env": "latest"
  }
}

The js script i want to run is app.js. I cannot run it directly using node app.js because app.js contains new language syntax.

Thus i have to run it through babel, using npm start, as per the start script defined above. No issues here.

My question is how to run the cmd directly in the command line, can it be done? something similar to:

npm run babel-node --presets env app.js

just FYI (and to make the link): the above question is related to [my question here](https://stackoverflow.com/questions/53874360/how-does-mocha-babel-transpile-my-test-code-on-the-fly) — Frank Nocke, Jan 06 '19 at 07:58

score 18 · Accepted Answer · edited Apr 08 '20 at 16:07

18

node ./node_modules/babel-cli/bin/babel-node.js --presets env app.js

edited Apr 08 '20 at 16:07

Vic Seedoubleyew

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answered Jul 26 '18 at 02:52

Rodrigo Mata

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node ./node_modules/babel-cli/bin/babel-node.js --presets env app.js . NB: its actually under babel-cli. if you change your answer, i wiil accept it – joedotnot Jul 26 '18 at 05:58
4

For anyway reading this in 2020, with Babel v7 things have changed quite a bit ! You may need to look elsewhere rather than this accepted answer, which works with Babel 6 ! – joedotnot Jan 01 '20 at 15:42
I ended up staying with Babel 6, instead of upgrading to Babel 7, just so I didn't have to deal with this regression. – Ben S Jan 28 '20 at 13:35

Viktor Vlasenko · Answer 2 · 2019-08-31T11:40:47.723

16

You can execute npm package binaries with npx.

Because Babel 7 always resolves plugins and presets relative to local project folder, you will have to install @babel/preset-env locally into the project.

npm i -D @babel/preset-env

After that the babel-node can be run with npx without installation into the project:

npx -p @babel/core -p @babel/node babel-node --presets @babel/preset-env app.js

If you install @babel/node into the project, npx will prefer project-local version.

In case of Babel 6 the command below can be used:

npx babel-node --presets env app.js

edited Aug 31 '19 at 11:40

answered Jul 26 '18 at 06:15

Viktor Vlasenko

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In 2019: `npx babel-node --presets @babel/preset-env app.js` – Arne Jenssen Aug 26 '19 at 08:06
@ArneJenssen Thank you. Updated my answer. With Babel 7 it is actually much harder than it was with Babel 6, unfortunately – Viktor Vlasenko Aug 31 '19 at 11:35

score 13 · Answer 3 · answered Feb 18 '19 at 21:39

13

Great gugley mugleys! This was way harder than it should have been.

See here for docs. TLDR;

Babel > version 7.0 has to go in your package.json to run from command line.

npm install --save-dev @babel/core @babel/cli @babel/preset-env @babel/node 

npx babel-node --presets @babel/preset-env imports/test.js

answered Feb 18 '19 at 21:39

Michael Cole

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Excellent, thanks! "_By default, npx will check whether exists in $PATH, or in the local project binaries, and execute that."_ [npmjs.com/package/npx](https://www.npmjs.com/package/npx) – ptim Jul 01 '19 at 22:45

score 7 · Answer 4 · answered Jul 26 '18 at 02:55

Install @babe/node globally-

npm i -g @babel/node

then babel-node command becomes available in your terminal. So, you can run -

babel-node --presets env app.js

Btw, it should be used in dev environment only, never recommended for production as it's unnecessarily heavy with high memory usage.

score 1 · Answer 5 · answered Jan 24 '19 at 16:28

Babel node has a bin registered so an executable is generated on install inside the node_modules/.bin directory.

You may run it simply by typing.

node_modules/.bin/babel-node --presets env app.js

Which accomplishes the same thing as the longer node or the alternate npx versions.

score 1 · Answer 6 · answered Apr 22 '20 at 21:12

1

in babel 7 you can run this:

npx babel app.js

answered Apr 22 '20 at 21:12

alayor

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Will `npx` (unlike Rodrigo's V6 answer above) pull all the required node_modules into cache? (Thus doing a lot more than on-the-fly-transpile+execution of local source code? Because I'd rather limit myself to that). — or is this not the case, when a local file (`app.js`) is given as parameter? – Frank Nocke Jul 21 '20 at 10:53

score -2 · Answer 7 · edited Jan 14 '20 at 19:41

-2

You can run the app.js file from node by telling it about babel-node first:

node ./node_modules/.bin/babel-node app.js

with the following .babelrc file at the root project

{"presets": ["@babel/preset-env"]}

edited Jan 14 '20 at 19:41

Bob Dalgleish

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answered Jan 14 '20 at 17:18

Christophe Gougeon

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how to run node / babel script directly in command line?

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