A tiny warning alternative.

import warning from 'tiny-warning';
warning(truthyValue, 'This should not log a warning');
warning(falsyValue, 'This should log a warning');
// console.warn('Warning: This should log a warning');

• condition is required and can be anything
• message is a required string that will be passed onto console.warn

The library: warning supports passing in arguments to the warning function in a sprintf style (condition, format, a, b, c, d, e, f). It has internal logic to execute the sprintf substitutions. tiny-warning has dropped all of the sprintf logic. tiny-warning allows you to pass a single string message. With template literals there is really no need for a custom message formatter to be built into the library. If you need a multi part message you can just do this: warning(condition, 'Hello, ${name} - how are you today?')

We recommend using babel-plugin-dev-expression to remove warning calls from your production build. This saves you kb's as well as avoids logging warnings to the console for production.

What it does it turn your code that looks like this:

warning(condition, 'My cool message that takes up a lot of kbs');

Into this

if ('production' !== process.env.NODE_ENV) {
  warning(condition, 'My cool message that takes up a lot of kbs');
}

Your bundler can then drop the code in the "production" !== process.env.NODE_ENV block for your production builds

Final result:

// nothing to see here! 👍

For rollup use rollup-plugin-replace and set NODE_ENV to production and then rollup will treeshake out the unused code

Webpack instructions

• We have a es (EcmaScript module) build (because you know you want to deduplicate this super heavy library)
• We have a cjs (CommonJS) build
• We have a umd (Universal module definition) build in case you needed it

We expect process.env.NODE_ENV to be available at module compilation. We cache this value

🤘