sugar/range/internal/rangeEvery.js

A Javascript utility library for working with native objects.

'use strict';

var classChecks = require('../../common/var/classChecks'),
    rangeIsValid = require('./rangeIsValid'),
    incrementDate = require('./incrementDate'),
    incrementNumber = require('./incrementNumber'),
    incrementString = require('./incrementString'),
    getGreaterPrecision = require('./getGreaterPrecision'),
    getDateIncrementObject = require('./getDateIncrementObject');

var isNumber = classChecks.isNumber,
    isString = classChecks.isString,
    isDate = classChecks.isDate,
    isFunction = classChecks.isFunction;

function rangeEvery(range, step, countOnly, fn) {
  var increment,
      precision,
      dio,
      unit,
      start   = range.start,
      end     = range.end,
      inverse = end < start,
      current = start,
      index   = 0,
      result  = [];

  if (!rangeIsValid(range)) {
    return countOnly ? NaN : [];
  }
  if (isFunction(step)) {
    fn = step;
    step = null;
  }
  step = step || 1;
  if (isNumber(start)) {
    precision = getGreaterPrecision(start, step);
    increment = function() {
      return incrementNumber(current, step, precision);
    };
  } else if (isString(start)) {
    increment = function() {
      return incrementString(current, step);
    };
  } else if (isDate(start)) {
    dio  = getDateIncrementObject(step);
    step = dio[0];
    unit = dio[1];
    increment = function() {
      return incrementDate(current, step, unit);
    };
  }
  // Avoiding infinite loops
  if (inverse && step > 0) {
    step *= -1;
  }
  while(inverse ? current >= end : current <= end) {
    if (!countOnly) {
      result.push(current);
    }
    if (fn) {
      fn(current, index, range);
    }
    current = increment();
    index++;
  }
  return countOnly ? index - 1 : result;
}

module.exports = rangeEvery;