Allow disabling of console clearing

[hyperknot]

When debugging an ejected script via console.logging different things, I found it quite difficult / annoying that multiple pieces of this script clear the the console when it detects stdout.isTTY (start.js and react-dev-utils/WebpackDevServerUtils.js).

I would like to recommend some kind of argument or environment variable to disable that behaviour, so that we wouldn't need to eject and modify and clone to simply enable console logging.

[viankakrisna]

a detection of env variable (maybe REACT_APP_NO_CLEAR_CONSOLE) in here should do it https://github.com/facebookincubator/create-react-app/blob/master/packages/react-dev-utils/clearConsole.js#L13-L15

[hyperknot]

@viankakrisna yes, that's a good idea as well!

[Timer]

I'm not sure this is going to be something we allow; why not edit the file in node_modules/ while debugging?

And you really shouldn't be using console debugging anyway 😅. Why not use something like VSCode with built-in debug support?

[viankakrisna]

@Timer is there any more alternative? I've been doing console.log debugging in node since forever and don't want to switch editor :D

[Timer]

You can boot up with node debug or node --inspect and then open chrome to the provided URL and use devtools.

[viankakrisna]

@Timer thanks! That's new to me. So that's how people inspect a nested objects in node huh? I thought everyone uses their terminal for debugging node code.... However, I've tried it in CRA repo but the instruction is quickly cleared for --inspect

"scripts": {
    "build": "node --inspect packages/react-scripts/scripts/build.js",
    "changelog": "lerna-changelog",
    "create-react-app": "tasks/cra.sh",
    "e2e": "tasks/e2e-simple.sh",
    "postinstall": "lerna bootstrap && cd packages/react-error-overlay/ && npm run build:prod",
    "publish": "tasks/release.sh",
    "start": "node --inspect packages/react-scripts/scripts/start.js",
    "test": "node --inspect packages/react-scripts/scripts/test.js --env=jsdom",
    "format": "prettier --trailing-comma es5 --single-quote --write 'packages/*/*.js' 'packages/*/!(node_modules)/**/*.js'",
    "precommit": "lint-staged"
  },

using node debug is not practical because it executes the script line by line... So i think configuring console clearing behavior could be added? 😄 or detect whether the current script is started using debug / --inspect.

I will happily add PR for contributing.md (or the root package.json) for this if we can also improve Contributor's Experience (CX?) :)

[michaek]

I think this is worth considering, as the current console experience seems very strange to me. Clearing the console is kind of nice aesthetically (though not that important, in my opinion), but currently all output history in the console session is removed after running start which seems like something you would never actually want.

[SeanCannon]

The REACT_APP_NO_CLEAR_CONSOLE env var is a great idea.

[viankakrisna]

or run it with FORCE_COLOR=true npm start | cat or FORCE_COLOR=true yarn start | cat if you use yarn. Taken from https://github.com/reasonml-community/reason-scripts#help-tips-and-tricks

Please can we add REACT_APP_NO_CLEAR_CONSOLE env var. Using Windows, OSX, Linux is a nightmare!

@viankakrisna and on Windows?