Super-simple invariant function
npm install simple-invariant
It's the simplest possible invariant/assert function. The code is:
``js`
function invariant( condition, message ) {
if ( !condition ) {
throw new Error( message || 'Invariant failed' );
}
};
So, this code:
`js`
if ( !foo ) throw new Error( 'foo must be truthy' );
...can be replaced with the shorter:
`js`
invariant( foo, 'foo must be truthy' );
Pretty much. The only difference is that the error thrown will always have the full error message, regardless of whether process.env.NODE_ENV === 'production' or not.
This module follows semver. Breaking changes will only be made in major version updates.
All active NodeJS release lines are supported (v10+ at time of writing). After a release line of NodeJS reaches end of life according to Node's LTS schedule, support for that version of Node may be dropped at any time, and this will not be considered a breaking change. Dropping support for a Node version will be made in a minor version update (e.g. 1.2.0 to 1.3.0). If you are using a Node version which is approaching end of life, pin your dependency of this module to patch updates only using tilde (~) e.g. ~1.2.3 to avoid breakages.
Use npm test to run the tests. Use npm run cover` to check coverage.
See changelog.md
If you discover a bug, please raise an issue on Github. https://github.com/overlookmotel/simple-invariant/issues
Pull requests are very welcome. Please:
* ensure all tests pass before submitting PR
* add tests for new features
* document new functionality/API additions in README
* do not add an entry to Changelog (Changelog is created when cutting releases)