TypeScript property change trace logs

tracePropertyChanges.ts

/**
 * Logs information whenever a decorated propery's value is changed.
 * The log message will contain the previous value, the new value and a stack trace.
 * @param message An optional message to write to the console when a change is detected.
 * @example
 *     class Foo {
 *         @tracePropertyChanges('Foo bar')
 *         public bar: any;
 *     }
 * 
 *     const foo = new Foo();
 *     foo.bar = 123; // will log "CHANGE: Foo bar (bar) ..."
 */
export function tracePropertyChanges(message: string = '') {
	return (target: any, key: string) => {
		let value: any;

		Object.defineProperty(target, key, {
			get: () => value,
			set: newValue => {
				// tslint:disable:no-console
				console.group(`CHANGE: ${message} (${key})`);
				console.log('from', value, 'to', newValue);
				console.trace();
				console.groupEnd();
				// tslint:enable:no-console

				value = newValue;
			}
		});
	};
}