/**
 * Graphology isGraphConstructor
 * ==============================
 *
 * Very simple function aiming at ensuring the given variable is a
 * graphology constructor.
 */

/**
 * Checking the value is a graphology constructor.
 *
 * @param  {any}     value - Target value.
 * @return {boolean}
 */
module.exports = function isGraphConstructor(value) {
  return (
    value !== null &&
    typeof value === 'function' &&
    typeof value.prototype === 'object' &&
    typeof value.prototype.addUndirectedEdgeWithKey === 'function' &&
    typeof value.prototype.dropNode === 'function'
  );
};