stable-function

Ensure a function is stable, meaning the same input always produces the same output

Useful for stress testing functions in your unit tests to make sure their behaviors are consistent.

Install

npm install stable-function

Usage

import stableFunction from 'stable-function';

stableFunction(() => true);
//=> true

let index = 0;
stableFunction.returnValue(100, () => {
	if (++index === 10) {
		return 'bar';
	}

	return 'foo';
});
//=> 'bar'

API

stableFunction(count?, testFunction)

Returns a boolean whether the output of testFunction was stable.

stableFunction.returnValue(count?, testFunction)

Returns the first differing output of testFunction or the first output if stable.

count

Type: number Default: 1000

The number of times to call the testFunction.

testFunction

Type: function

The function to be tested.