luhn-generator/update/node_modules/jsx-ast-utils/lib/values/expressions/UnaryExpression.js

A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = extractValueFromUnaryExpression;
/**
 * Extractor function for a UnaryExpression type value node.
 * A unary expression is an expression with a unary operator.
 * For example, !"foobar" will evaluate to false, so this will return false.
 *
 * @param - value - AST Value object with type `UnaryExpression`
 * @returns - The extracted value converted to correct type.
 */
function extractValueFromUnaryExpression(value) {
  // eslint-disable-next-line global-require
  var getValue = require('./index.js').default;
  var operator = value.operator,
      argument = value.argument;


  switch (operator) {
    case '-':
      return -getValue(argument);
    case '+':
      return +getValue(argument); // eslint-disable-line no-implicit-coercion
    case '!':
      return !getValue(argument);
    case '~':
      return ~getValue(argument); // eslint-disable-line no-bitwise
    case 'delete':
      // I believe delete statements evaluate to true.
      return true;
    case 'typeof':
    case 'void':
    default:
      return undefined;
  }
}