13 files changed, 721 insertions, 0 deletions
diff --git a/node_modules/moment/src/lib/duration/abs.js b/node_modules/moment/src/lib/duration/abs.js
new file mode 100644
index 0000000..d61ebe6
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/abs.js
@@ -0,0 +1,18 @@
+var mathAbs = Math.abs;
+
+export function abs() {
+    var data = this._data;
+
+    this._milliseconds = mathAbs(this._milliseconds);
+    this._days = mathAbs(this._days);
+    this._months = mathAbs(this._months);
+
+    data.milliseconds = mathAbs(data.milliseconds);
+    data.seconds = mathAbs(data.seconds);
+    data.minutes = mathAbs(data.minutes);
+    data.hours = mathAbs(data.hours);
+    data.months = mathAbs(data.months);
+    data.years = mathAbs(data.years);
+
+    return this;
+}
diff --git a/node_modules/moment/src/lib/duration/add-subtract.js b/node_modules/moment/src/lib/duration/add-subtract.js
new file mode 100644
index 0000000..3755a7d
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/add-subtract.js
@@ -0,0 +1,21 @@
+import { createDuration } from './create';
+
+function addSubtract(duration, input, value, direction) {
+    var other = createDuration(input, value);
+
+    duration._milliseconds += direction * other._milliseconds;
+    duration._days += direction * other._days;
+    duration._months += direction * other._months;
+
+    return duration._bubble();
+}
+
+// supports only 2.0-style add(1, 's') or add(duration)
+export function add(input, value) {
+    return addSubtract(this, input, value, 1);
+}
+
+// supports only 2.0-style subtract(1, 's') or subtract(duration)
+export function subtract(input, value) {
+    return addSubtract(this, input, value, -1);
+}
diff --git a/node_modules/moment/src/lib/duration/as.js b/node_modules/moment/src/lib/duration/as.js
new file mode 100644
index 0000000..a620d5b
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/as.js
@@ -0,0 +1,76 @@
+import { daysToMonths, monthsToDays } from './bubble';
+import { normalizeUnits } from '../units/aliases';
+
+export function as(units) {
+    if (!this.isValid()) {
+        return NaN;
+    }
+    var days,
+        months,
+        milliseconds = this._milliseconds;
+
+    units = normalizeUnits(units);
+
+    if (units === 'month' || units === 'quarter' || units === 'year') {
+        days = this._days + milliseconds / 864e5;
+        months = this._months + daysToMonths(days);
+        switch (units) {
+            case 'month':
+                return months;
+            case 'quarter':
+                return months / 3;
+            case 'year':
+                return months / 12;
+        }
+    } else {
+        // handle milliseconds separately because of floating point math errors (issue #1867)
+        days = this._days + Math.round(monthsToDays(this._months));
+        switch (units) {
+            case 'week':
+                return days / 7 + milliseconds / 6048e5;
+            case 'day':
+                return days + milliseconds / 864e5;
+            case 'hour':
+                return days * 24 + milliseconds / 36e5;
+            case 'minute':
+                return days * 1440 + milliseconds / 6e4;
+            case 'second':
+                return days * 86400 + milliseconds / 1000;
+            // Math.floor prevents floating point math errors here
+            case 'millisecond':
+                return Math.floor(days * 864e5) + milliseconds;
+            default:
+                throw new Error('Unknown unit ' + units);
+        }
+    }
+}
+
+function makeAs(alias) {
+    return function () {
+        return this.as(alias);
+    };
+}
+
+var asMilliseconds = makeAs('ms'),
+    asSeconds = makeAs('s'),
+    asMinutes = makeAs('m'),
+    asHours = makeAs('h'),
+    asDays = makeAs('d'),
+    asWeeks = makeAs('w'),
+    asMonths = makeAs('M'),
+    asQuarters = makeAs('Q'),
+    asYears = makeAs('y'),
+    valueOf = asMilliseconds;
+
+export {
+    asMilliseconds,
+    asSeconds,
+    asMinutes,
+    asHours,
+    asDays,
+    asWeeks,
+    asMonths,
+    asQuarters,
+    asYears,
+    valueOf,
+};
diff --git a/node_modules/moment/src/lib/duration/bubble.js b/node_modules/moment/src/lib/duration/bubble.js
new file mode 100644
index 0000000..c7822e3
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/bubble.js
@@ -0,0 +1,68 @@
+import absFloor from '../utils/abs-floor';
+import absCeil from '../utils/abs-ceil';
+
+export function bubble() {
+    var milliseconds = this._milliseconds,
+        days = this._days,
+        months = this._months,
+        data = this._data,
+        seconds,
+        minutes,
+        hours,
+        years,
+        monthsFromDays;
+
+    // if we have a mix of positive and negative values, bubble down first
+    // check: https://github.com/moment/moment/issues/2166
+    if (
+        !(
+            (milliseconds >= 0 && days >= 0 && months >= 0) ||
+            (milliseconds <= 0 && days <= 0 && months <= 0)
+        )
+    ) {
+        milliseconds += absCeil(monthsToDays(months) + days) * 864e5;
+        days = 0;
+        months = 0;
+    }
+
+    // The following code bubbles up values, see the tests for
+    // examples of what that means.
+    data.milliseconds = milliseconds % 1000;
+
+    seconds = absFloor(milliseconds / 1000);
+    data.seconds = seconds % 60;
+
+    minutes = absFloor(seconds / 60);
+    data.minutes = minutes % 60;
+
+    hours = absFloor(minutes / 60);
+    data.hours = hours % 24;
+
+    days += absFloor(hours / 24);
+
+    // convert days to months
+    monthsFromDays = absFloor(daysToMonths(days));
+    months += monthsFromDays;
+    days -= absCeil(monthsToDays(monthsFromDays));
+
+    // 12 months -> 1 year
+    years = absFloor(months / 12);
+    months %= 12;
+
+    data.days = days;
+    data.months = months;
+    data.years = years;
+
+    return this;
+}
+
+export function daysToMonths(days) {
+    // 400 years have 146097 days (taking into account leap year rules)
+    // 400 years have 12 months === 4800
+    return (days * 4800) / 146097;
+}
+
+export function monthsToDays(months) {
+    // the reverse of daysToMonths
+    return (months * 146097) / 4800;
+}
diff --git a/node_modules/moment/src/lib/duration/clone.js b/node_modules/moment/src/lib/duration/clone.js
new file mode 100644
index 0000000..8978dfe
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/clone.js
@@ -0,0 +1,5 @@
+import { createDuration } from './create';
+
+export function clone() {
+    return createDuration(this);
+}
diff --git a/node_modules/moment/src/lib/duration/constructor.js b/node_modules/moment/src/lib/duration/constructor.js
new file mode 100644
index 0000000..6033769
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/constructor.js
@@ -0,0 +1,42 @@
+import { normalizeObjectUnits } from '../units/aliases';
+import { getLocale } from '../locale/locales';
+import isDurationValid from './valid.js';
+
+export function Duration(duration) {
+    var normalizedInput = normalizeObjectUnits(duration),
+        years = normalizedInput.year || 0,
+        quarters = normalizedInput.quarter || 0,
+        months = normalizedInput.month || 0,
+        weeks = normalizedInput.week || normalizedInput.isoWeek || 0,
+        days = normalizedInput.day || 0,
+        hours = normalizedInput.hour || 0,
+        minutes = normalizedInput.minute || 0,
+        seconds = normalizedInput.second || 0,
+        milliseconds = normalizedInput.millisecond || 0;
+
+    this._isValid = isDurationValid(normalizedInput);
+
+    // representation for dateAddRemove
+    this._milliseconds =
+        +milliseconds +
+        seconds * 1e3 + // 1000
+        minutes * 6e4 + // 1000 * 60
+        hours * 1000 * 60 * 60; //using 1000 * 60 * 60 instead of 36e5 to avoid floating point rounding errors https://github.com/moment/moment/issues/2978
+    // Because of dateAddRemove treats 24 hours as different from a
+    // day when working around DST, we need to store them separately
+    this._days = +days + weeks * 7;
+    // It is impossible to translate months into days without knowing
+    // which months you are are talking about, so we have to store
+    // it separately.
+    this._months = +months + quarters * 3 + years * 12;
+
+    this._data = {};
+
+    this._locale = getLocale();
+
+    this._bubble();
+}
+
+export function isDuration(obj) {
+    return obj instanceof Duration;
+}
diff --git a/node_modules/moment/src/lib/duration/create.js b/node_modules/moment/src/lib/duration/create.js
new file mode 100644
index 0000000..a82c376
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/create.js
@@ -0,0 +1,133 @@
+import { Duration, isDuration } from './constructor';
+import isNumber from '../utils/is-number';
+import toInt from '../utils/to-int';
+import absRound from '../utils/abs-round';
+import hasOwnProp from '../utils/has-own-prop';
+import { DATE, HOUR, MINUTE, SECOND, MILLISECOND } from '../units/constants';
+import { cloneWithOffset } from '../units/offset';
+import { createLocal } from '../create/local';
+import { createInvalid as invalid } from './valid';
+
+// ASP.NET json date format regex
+var aspNetRegex = /^(-|\+)?(?:(\d*)[. ])?(\d+):(\d+)(?::(\d+)(\.\d*)?)?$/,
+    // from http://docs.closure-library.googlecode.com/git/closure_goog_date_date.js.source.html
+    // somewhat more in line with 4.4.3.2 2004 spec, but allows decimal anywhere
+    // and further modified to allow for strings containing both week and day
+    isoRegex =
+        /^(-|\+)?P(?:([-+]?[0-9,.]*)Y)?(?:([-+]?[0-9,.]*)M)?(?:([-+]?[0-9,.]*)W)?(?:([-+]?[0-9,.]*)D)?(?:T(?:([-+]?[0-9,.]*)H)?(?:([-+]?[0-9,.]*)M)?(?:([-+]?[0-9,.]*)S)?)?$/;
+
+export function createDuration(input, key) {
+    var duration = input,
+        // matching against regexp is expensive, do it on demand
+        match = null,
+        sign,
+        ret,
+        diffRes;
+
+    if (isDuration(input)) {
+        duration = {
+            ms: input._milliseconds,
+            d: input._days,
+            M: input._months,
+        };
+    } else if (isNumber(input) || !isNaN(+input)) {
+        duration = {};
+        if (key) {
+            duration[key] = +input;
+        } else {
+            duration.milliseconds = +input;
+        }
+    } else if ((match = aspNetRegex.exec(input))) {
+        sign = match[1] === '-' ? -1 : 1;
+        duration = {
+            y: 0,
+            d: toInt(match[DATE]) * sign,
+            h: toInt(match[HOUR]) * sign,
+            m: toInt(match[MINUTE]) * sign,
+            s: toInt(match[SECOND]) * sign,
+            ms: toInt(absRound(match[MILLISECOND] * 1000)) * sign, // the millisecond decimal point is included in the match
+        };
+    } else if ((match = isoRegex.exec(input))) {
+        sign = match[1] === '-' ? -1 : 1;
+        duration = {
+            y: parseIso(match[2], sign),
+            M: parseIso(match[3], sign),
+            w: parseIso(match[4], sign),
+            d: parseIso(match[5], sign),
+            h: parseIso(match[6], sign),
+            m: parseIso(match[7], sign),
+            s: parseIso(match[8], sign),
+        };
+    } else if (duration == null) {
+        // checks for null or undefined
+        duration = {};
+    } else if (
+        typeof duration === 'object' &&
+        ('from' in duration || 'to' in duration)
+    ) {
+        diffRes = momentsDifference(
+            createLocal(duration.from),
+            createLocal(duration.to)
+        );
+
+        duration = {};
+        duration.ms = diffRes.milliseconds;
+        duration.M = diffRes.months;
+    }
+
+    ret = new Duration(duration);
+
+    if (isDuration(input) && hasOwnProp(input, '_locale')) {
+        ret._locale = input._locale;
+    }
+
+    if (isDuration(input) && hasOwnProp(input, '_isValid')) {
+        ret._isValid = input._isValid;
+    }
+
+    return ret;
+}
+
+createDuration.fn = Duration.prototype;
+createDuration.invalid = invalid;
+
+function parseIso(inp, sign) {
+    // We'd normally use ~~inp for this, but unfortunately it also
+    // converts floats to ints.
+    // inp may be undefined, so careful calling replace on it.
+    var res = inp && parseFloat(inp.replace(',', '.'));
+    // apply sign while we're at it
+    return (isNaN(res) ? 0 : res) * sign;
+}
+
+function positiveMomentsDifference(base, other) {
+    var res = {};
+
+    res.months =
+        other.month() - base.month() + (other.year() - base.year()) * 12;
+    if (base.clone().add(res.months, 'M').isAfter(other)) {
+        --res.months;
+    }
+
+    res.milliseconds = +other - +base.clone().add(res.months, 'M');
+
+    return res;
+}
+
+function momentsDifference(base, other) {
+    var res;
+    if (!(base.isValid() && other.isValid())) {
+        return { milliseconds: 0, months: 0 };
+    }
+
+    other = cloneWithOffset(other, base);
+    if (base.isBefore(other)) {
+        res = positiveMomentsDifference(base, other);
+    } else {
+        res = positiveMomentsDifference(other, base);
+        res.milliseconds = -res.milliseconds;
+        res.months = -res.months;
+    }
+
+    return res;
+}
diff --git a/node_modules/moment/src/lib/duration/duration.js b/node_modules/moment/src/lib/duration/duration.js
new file mode 100644
index 0000000..10f03a7
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/duration.js
@@ -0,0 +1,16 @@
+// Side effect imports
+import './prototype';
+
+import { createDuration } from './create';
+import { isDuration } from './constructor';
+import {
+    getSetRelativeTimeRounding,
+    getSetRelativeTimeThreshold,
+} from './humanize';
+
+export {
+    createDuration,
+    isDuration,
+    getSetRelativeTimeRounding,
+    getSetRelativeTimeThreshold,
+};
diff --git a/node_modules/moment/src/lib/duration/get.js b/node_modules/moment/src/lib/duration/get.js
new file mode 100644
index 0000000..99533d7
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/get.js
@@ -0,0 +1,27 @@
+import { normalizeUnits } from '../units/aliases';
+import absFloor from '../utils/abs-floor';
+
+export function get(units) {
+    units = normalizeUnits(units);
+    return this.isValid() ? this[units + 's']() : NaN;
+}
+
+function makeGetter(name) {
+    return function () {
+        return this.isValid() ? this._data[name] : NaN;
+    };
+}
+
+var milliseconds = makeGetter('milliseconds'),
+    seconds = makeGetter('seconds'),
+    minutes = makeGetter('minutes'),
+    hours = makeGetter('hours'),
+    days = makeGetter('days'),
+    months = makeGetter('months'),
+    years = makeGetter('years');
+
+export { milliseconds, seconds, minutes, hours, days, months, years };
+
+export function weeks() {
+    return absFloor(this.days() / 7);
+}
diff --git a/node_modules/moment/src/lib/duration/humanize.js b/node_modules/moment/src/lib/duration/humanize.js
new file mode 100644
index 0000000..74079cd
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/humanize.js
@@ -0,0 +1,114 @@
+import { createDuration } from './create';
+
+var round = Math.round,
+    thresholds = {
+        ss: 44, // a few seconds to seconds
+        s: 45, // seconds to minute
+        m: 45, // minutes to hour
+        h: 22, // hours to day
+        d: 26, // days to month/week
+        w: null, // weeks to month
+        M: 11, // months to year
+    };
+
+// helper function for moment.fn.from, moment.fn.fromNow, and moment.duration.fn.humanize
+function substituteTimeAgo(string, number, withoutSuffix, isFuture, locale) {
+    return locale.relativeTime(number || 1, !!withoutSuffix, string, isFuture);
+}
+
+function relativeTime(posNegDuration, withoutSuffix, thresholds, locale) {
+    var duration = createDuration(posNegDuration).abs(),
+        seconds = round(duration.as('s')),
+        minutes = round(duration.as('m')),
+        hours = round(duration.as('h')),
+        days = round(duration.as('d')),
+        months = round(duration.as('M')),
+        weeks = round(duration.as('w')),
+        years = round(duration.as('y')),
+        a =
+            (seconds <= thresholds.ss && ['s', seconds]) ||
+            (seconds < thresholds.s && ['ss', seconds]) ||
+            (minutes <= 1 && ['m']) ||
+            (minutes < thresholds.m && ['mm', minutes]) ||
+            (hours <= 1 && ['h']) ||
+            (hours < thresholds.h && ['hh', hours]) ||
+            (days <= 1 && ['d']) ||
+            (days < thresholds.d && ['dd', days]);
+
+    if (thresholds.w != null) {
+        a =
+            a ||
+            (weeks <= 1 && ['w']) ||
+            (weeks < thresholds.w && ['ww', weeks]);
+    }
+    a = a ||
+        (months <= 1 && ['M']) ||
+        (months < thresholds.M && ['MM', months]) ||
+        (years <= 1 && ['y']) || ['yy', years];
+
+    a[2] = withoutSuffix;
+    a[3] = +posNegDuration > 0;
+    a[4] = locale;
+    return substituteTimeAgo.apply(null, a);
+}
+
+// This function allows you to set the rounding function for relative time strings
+export function getSetRelativeTimeRounding(roundingFunction) {
+    if (roundingFunction === undefined) {
+        return round;
+    }
+    if (typeof roundingFunction === 'function') {
+        round = roundingFunction;
+        return true;
+    }
+    return false;
+}
+
+// This function allows you to set a threshold for relative time strings
+export function getSetRelativeTimeThreshold(threshold, limit) {
+    if (thresholds[threshold] === undefined) {
+        return false;
+    }
+    if (limit === undefined) {
+        return thresholds[threshold];
+    }
+    thresholds[threshold] = limit;
+    if (threshold === 's') {
+        thresholds.ss = limit - 1;
+    }
+    return true;
+}
+
+export function humanize(argWithSuffix, argThresholds) {
+    if (!this.isValid()) {
+        return this.localeData().invalidDate();
+    }
+
+    var withSuffix = false,
+        th = thresholds,
+        locale,
+        output;
+
+    if (typeof argWithSuffix === 'object') {
+        argThresholds = argWithSuffix;
+        argWithSuffix = false;
+    }
+    if (typeof argWithSuffix === 'boolean') {
+        withSuffix = argWithSuffix;
+    }
+    if (typeof argThresholds === 'object') {
+        th = Object.assign({}, thresholds, argThresholds);
+        if (argThresholds.s != null && argThresholds.ss == null) {
+            th.ss = argThresholds.s - 1;
+        }
+    }
+
+    locale = this.localeData();
+    output = relativeTime(this, !withSuffix, th, locale);
+
+    if (withSuffix) {
+        output = locale.pastFuture(+this, output);
+    }
+
+    return locale.postformat(output);
+}
diff --git a/node_modules/moment/src/lib/duration/iso-string.js b/node_modules/moment/src/lib/duration/iso-string.js
new file mode 100644
index 0000000..5fd2166
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/iso-string.js
@@ -0,0 +1,68 @@
+import absFloor from '../utils/abs-floor';
+var abs = Math.abs;
+
+function sign(x) {
+    return (x > 0) - (x < 0) || +x;
+}
+
+export function toISOString() {
+    // for ISO strings we do not use the normal bubbling rules:
+    //  * milliseconds bubble up until they become hours
+    //  * days do not bubble at all
+    //  * months bubble up until they become years
+    // This is because there is no context-free conversion between hours and days
+    // (think of clock changes)
+    // and also not between days and months (28-31 days per month)
+    if (!this.isValid()) {
+        return this.localeData().invalidDate();
+    }
+
+    var seconds = abs(this._milliseconds) / 1000,
+        days = abs(this._days),
+        months = abs(this._months),
+        minutes,
+        hours,
+        years,
+        s,
+        total = this.asSeconds(),
+        totalSign,
+        ymSign,
+        daysSign,
+        hmsSign;
+
+    if (!total) {
+        // this is the same as C#'s (Noda) and python (isodate)...
+        // but not other JS (goog.date)
+        return 'P0D';
+    }
+
+    // 3600 seconds -> 60 minutes -> 1 hour
+    minutes = absFloor(seconds / 60);
+    hours = absFloor(minutes / 60);
+    seconds %= 60;
+    minutes %= 60;
+
+    // 12 months -> 1 year
+    years = absFloor(months / 12);
+    months %= 12;
+
+    // inspired by https://github.com/dordille/moment-isoduration/blob/master/moment.isoduration.js
+    s = seconds ? seconds.toFixed(3).replace(/\.?0+$/, '') : '';
+
+    totalSign = total < 0 ? '-' : '';
+    ymSign = sign(this._months) !== sign(total) ? '-' : '';
+    daysSign = sign(this._days) !== sign(total) ? '-' : '';
+    hmsSign = sign(this._milliseconds) !== sign(total) ? '-' : '';
+
+    return (
+        totalSign +
+        'P' +
+        (years ? ymSign + years + 'Y' : '') +
+        (months ? ymSign + months + 'M' : '') +
+        (days ? daysSign + days + 'D' : '') +
+        (hours || minutes || seconds ? 'T' : '') +
+        (hours ? hmsSign + hours + 'H' : '') +
+        (minutes ? hmsSign + minutes + 'M' : '') +
+        (seconds ? hmsSign + s + 'S' : '')
+    );
+}
diff --git a/node_modules/moment/src/lib/duration/prototype.js b/node_modules/moment/src/lib/duration/prototype.js
new file mode 100644
index 0000000..3f24b4a
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/prototype.js
@@ -0,0 +1,78 @@
+import { Duration } from './constructor';
+
+var proto = Duration.prototype;
+
+import { abs } from './abs';
+import { add, subtract } from './add-subtract';
+import {
+    as,
+    asMilliseconds,
+    asSeconds,
+    asMinutes,
+    asHours,
+    asDays,
+    asWeeks,
+    asMonths,
+    asQuarters,
+    asYears,
+    valueOf,
+} from './as';
+import { bubble } from './bubble';
+import { clone } from './clone';
+import {
+    get,
+    milliseconds,
+    seconds,
+    minutes,
+    hours,
+    days,
+    months,
+    years,
+    weeks,
+} from './get';
+import { humanize } from './humanize';
+import { toISOString } from './iso-string';
+import { lang, locale, localeData } from '../moment/locale';
+import { isValid } from './valid';
+
+proto.isValid = isValid;
+proto.abs = abs;
+proto.add = add;
+proto.subtract = subtract;
+proto.as = as;
+proto.asMilliseconds = asMilliseconds;
+proto.asSeconds = asSeconds;
+proto.asMinutes = asMinutes;
+proto.asHours = asHours;
+proto.asDays = asDays;
+proto.asWeeks = asWeeks;
+proto.asMonths = asMonths;
+proto.asQuarters = asQuarters;
+proto.asYears = asYears;
+proto.valueOf = valueOf;
+proto._bubble = bubble;
+proto.clone = clone;
+proto.get = get;
+proto.milliseconds = milliseconds;
+proto.seconds = seconds;
+proto.minutes = minutes;
+proto.hours = hours;
+proto.days = days;
+proto.weeks = weeks;
+proto.months = months;
+proto.years = years;
+proto.humanize = humanize;
+proto.toISOString = toISOString;
+proto.toString = toISOString;
+proto.toJSON = toISOString;
+proto.locale = locale;
+proto.localeData = localeData;
+
+// Deprecations
+import { deprecate } from '../utils/deprecate';
+
+proto.toIsoString = deprecate(
+    'toIsoString() is deprecated. Please use toISOString() instead (notice the capitals)',
+    toISOString
+);
+proto.lang = lang;
diff --git a/node_modules/moment/src/lib/duration/valid.js b/node_modules/moment/src/lib/duration/valid.js
new file mode 100644
index 0000000..88ef7a9
--- /dev/null
+++ b/node_modules/moment/src/lib/duration/valid.js
@@ -0,0 +1,55 @@
+import hasOwnProp from '../utils/has-own-prop';
+import toInt from '../utils/to-int';
+import indexOf from '../utils/index-of';
+import { createDuration } from './create';
+
+var ordering = [
+    'year',
+    'quarter',
+    'month',
+    'week',
+    'day',
+    'hour',
+    'minute',
+    'second',
+    'millisecond',
+];
+
+export default function isDurationValid(m) {
+    var key,
+        unitHasDecimal = false,
+        i,
+        orderLen = ordering.length;
+    for (key in m) {
+        if (
+            hasOwnProp(m, key) &&
+            !(
+                indexOf.call(ordering, key) !== -1 &&
+                (m[key] == null || !isNaN(m[key]))
+            )
+        ) {
+            return false;
+        }
+    }
+
+    for (i = 0; i < orderLen; ++i) {
+        if (m[ordering[i]]) {
+            if (unitHasDecimal) {
+                return false; // only allow non-integers for smallest unit
+            }
+            if (parseFloat(m[ordering[i]]) !== toInt(m[ordering[i]])) {
+                unitHasDecimal = true;
+            }
+        }
+    }
+
+    return true;
+}
+
+export function isValid() {
+    return this._isValid;
+}
+
+export function createInvalid() {
+    return createDuration(NaN);
+}