Console.assert

assert(

condition?: boolean,

...data: any[]

): void;

assert(

value: any,

message?: string,

...optionalParams: any[]

): void;

console.assert() writes a message if value is falsy or omitted. It only writes a message and does not otherwise affect execution. The output always starts with "Assertion failed". If provided, message is formatted using util.format().

If value is truthy, nothing happens.

console.assert(true, 'does nothing');

console.assert(false, 'Whoops %s work', 'didn\'t');
// Assertion failed: Whoops didn't work

console.assert();
// Assertion failed

@param value

The value tested for being truthy.

@param message

All arguments besides value are used as error message.