Awesome
Learning ESLint
With Linter Rules from the Google JS Style Guide
Just one of the things I'm learning. https://github.com/hchiam/learning
Example command:
eslint *.js
To Use this Repo as a Template
npm install
Now you can see your .js code get auto-annotated with underlines in your code editor.
You can now also run a check in command line:
npm run lint
Secret Sauce (When Starting from Scratch)
npm install --save-dev eslint eslint-config-google
./node_modules/.bin/eslint --init
(Follow instructions.)
You should see .eslintrc.js and this inside it:
'extends': [
'google',
],
Bonus Special: Command Line Use
(Instead of only relying on editor.)
package.json
"scripts": {
...
"lint": "eslint index.js" /* "eslint ./" if you want it for all .js files */
},
Then in command line:
npm run lint
You should see a message that looks something like this:
# ...
/.../test-google-linter/index.js
7:25 error Missing semicolon semi
# (and a bunch of other messages)
Bonus Bonus: Auto-fix Problems
npm run lint will tell you what problems there are, but eslint --fix <filename.js> will perform fixes that can be automatically done on index.js:
eslint --fix index.js
Yet Another Bonus: Auto-Run Stuff Upon File Edits
If you install nodemon, you can do these cool things:
nodemon -x 'npm run lint' will auto-run the linter checks and print the results to the CLI every time you save index.js
nodemon index.js will auto-run the file every time you save index.js
nodemon -x 'npm run lint; node index.js' will do both of the above.
nodemon -w index.js -x 'npm run lint; plato -r -d report index.js; node index.js; open report/index.html' will auto-rerun all of the above, but also give you a report that includes MI score (after you've run npm install -g plato once).
To install nodemon, do this:
npm i -g nodemon # i = install; -g = globally
or
npm install --save-dev nodemon # <- this saves into dev dependencies
References:
https://www.youtube.com/watch?v=qhuFviJn-es
https://eslint.org/docs/user-guide/command-line-interface