Babel-plugin-transform-comment-to-assert NPM

babel-plugin-transform-comment-to-assert

replace commented expressions with assert statements

Install

$ npm install --save babel-plugin-transform-comment-to-assert

Usage

import * as babel from 'babel-core'
import plugin from 'babel-plugin-transform-comment-to-assert'

function replace (code) {
  return babel.transform(code, { babelrc: false, plugins: [plugin] }).code.trim();
};

replace('1 //=> 1')
//=> 'assert.deepEqual(1, 1);'

Objects:

replace('a = { a: 1 }; a //=> {a: 1}')
//=> 'a = { a: 1 };assert.deepEqual(a, { a: 1 });'

Results of function calls:

replace("(() => 'foo')() //=> 'bar'")
//=> "assert.deepEqual((() => 'foo')(), 'bar');"

It also supports console.log:

replace("console.log('foo') //=> 'bar'")
//=> "console.log('foo');assert.deepEqual('foo', 'bar');"

Throws:

replace(`
const a = () => {
  throw new Error('fail');
};
a() // throws Error
`);
/*=>
`const a = () => {
  throw new Error('fail');
};
assert.throws(() => a(), Error);`
*/

replace(`
const a = () => {
  throw new Error('fail');
};
a() // throws /fail/
`);
/*=>
`const a = () => {
  throw new Error('fail');
};
assert.throws(() => a(), /fail/);`
*/