Strova assert

Intro

Babel plugin that transforms commented assertions to Javascript code.

Basic usage

const func = (arg1, arg2) => {
  // assert arg1
  // assert arg2 : 2nd argument is null
  return arg1 + arg2;
}

by default is transformed to log warning:

const func = (arg1, arg2) => {
  if (!function (arg) {
    return sa.assert(arg, 'notNull', [], null, false);
  }(arg1)) console.warn('Assertion error: arg1');
  if (!function (arg) {
    return sa.assert(arg, 'notNull', [], null, false);
  }(arg2)) console.warn('2nd argument is null: arg2');

  return arg1 + arg2;
};

but it can be also transformed to throw the Error:

const func = (arg1, arg2) => {
  if (!function (arg) {
    return sa.assert(arg, 'notNull', [], null, false);
  }(arg1)) throw new Error('Assertion error: arg1');
  if (!function (arg) {
    return sa.assert(arg, 'notNull', [], null, false);
  }(arg2)) throw new Error('2nd argument is null: arg2');
  
  return arg1 + arg2;
}

Keyword	alias	meaning
reserved	!	nothing - Jsdoc uses ! for not null argument but notNull is default action. So ! is excluded to avoid confusion.
nullable	?	may be null, used for type checking if not null
notEmpty	#	string must contain white character, array must not be zero sized, object must have some properites<notBlank
notBlank	$	for string only - must not contain white characters only

Examples

Exampe01

Running example01.js by npm run example01 displays transformed example/foomodule.js in the console output.

Exampe02

Running example02.js by npm run example02 runs real world code using example/foomodule.js in default plugin configuration: assertion errors are logged in the console.

npm run example02:throw runs again example02.js but with throw profile, assertion errors are thrown and caught instead just only logging them.