4 files changed, 147 insertions, 0 deletions
diff --git a/date-fns/src/subBusinessDays/index.d.ts b/date-fns/src/subBusinessDays/index.d.ts
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+// This file is generated automatically by `scripts/build/typings.js`. Please, don't change it.
+
+import { subBusinessDays } from 'date-fns'
+export default subBusinessDays
diff --git a/date-fns/src/subBusinessDays/index.js b/date-fns/src/subBusinessDays/index.js
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+import toInteger from '../_lib/toInteger/index'
+import addBusinessDays from '../addBusinessDays/index'
+import requiredArgs from '../_lib/requiredArgs/index'
+
+/**
+ * @name subBusinessDays
+ * @category Day Helpers
+ * @summary Substract the specified number of business days (mon - fri) to the given date.
+ *
+ * @description
+ * Substract the specified number of business days (mon - fri) to the given date, ignoring weekends.
+ *
+ * @param {Date|Number} date - the date to be changed
+ * @param {Number} amount - the amount of business days to be subtracted. Positive decimals will be rounded using `Math.floor`, decimals less than zero will be rounded using `Math.ceil`.
+ * @returns {Date} the new date with the business days subtracted
+ * @throws {TypeError} 2 arguments required
+ *
+ * @example
+ * // Substract 10 business days from 1 September 2014:
+ * var result = subBusinessDays(new Date(2014, 8, 1), 10)
+ * //=> Mon Aug 18 2014 00:00:00 (skipped weekend days)
+ */
+export default function subBusinessDays(dirtyDate, dirtyAmount) {
+  requiredArgs(2, arguments)
+
+  var amount = toInteger(dirtyAmount)
+  return addBusinessDays(dirtyDate, -amount)
+}
diff --git a/date-fns/src/subBusinessDays/index.js.flow b/date-fns/src/subBusinessDays/index.js.flow
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+// @flow
+// This file is generated automatically by `scripts/build/typings.js`. Please, don't change it.
+
+export type Interval = {
+  start: Date | number,
+  end: Date | number,
+}
+
+export type Locale = {
+  code?: string,
+  formatDistance?: (...args: Array<any>) => any,
+  formatRelative?: (...args: Array<any>) => any,
+  localize?: {
+    ordinalNumber: (...args: Array<any>) => any,
+    era: (...args: Array<any>) => any,
+    quarter: (...args: Array<any>) => any,
+    month: (...args: Array<any>) => any,
+    day: (...args: Array<any>) => any,
+    dayPeriod: (...args: Array<any>) => any,
+  },
+  formatLong?: {
+    date: (...args: Array<any>) => any,
+    time: (...args: Array<any>) => any,
+    dateTime: (...args: Array<any>) => any,
+  },
+  match?: {
+    ordinalNumber: (...args: Array<any>) => any,
+    era: (...args: Array<any>) => any,
+    quarter: (...args: Array<any>) => any,
+    month: (...args: Array<any>) => any,
+    day: (...args: Array<any>) => any,
+    dayPeriod: (...args: Array<any>) => any,
+  },
+  options?: {
+    weekStartsOn?: 0 | 1 | 2 | 3 | 4 | 5 | 6,
+    firstWeekContainsDate?: 1 | 2 | 3 | 4 | 5 | 6 | 7,
+  },
+}
+
+export type Duration = {
+  years?: number,
+  months?: number,
+  weeks?: number,
+  days?: number,
+  hours?: number,
+  minutes?: number,
+  seconds?: number,
+}
+
+export type Day = 0 | 1 | 2 | 3 | 4 | 5 | 6
+
+declare module.exports: (date: Date | number, amount: number) => Date
diff --git a/date-fns/src/subBusinessDays/test.js b/date-fns/src/subBusinessDays/test.js
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+++ b/date-fns/src/subBusinessDays/test.js
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+// @flow
+/* eslint-env mocha */
+
+import assert from 'power-assert'
+import subBusinessDays from '.'
+
+describe('subBusinessDays', function() {
+  it('substract the given number of business days', function() {
+    const result = subBusinessDays(new Date(2014, 8 /* Sep */, 1), 10)
+    assert.deepEqual(result, new Date(2014, 7 /* Aug */, 18))
+  })
+
+  it('handles negative amount', function() {
+    var result = subBusinessDays(new Date(2014, 7 /* Sep */, 18), -10)
+    assert.deepEqual(result, new Date(2014, 8 /* Sep */, 1))
+  })
+
+  it('can handle a large number of business days', function() {
+    if (typeof this.timeout === 'function') {
+      this.timeout(500 /* 500 ms test timeout */)
+    }
+
+    var result = subBusinessDays(new Date(15000, 0 /* Jan */, 1), 3387885)
+    assert.deepEqual(result, new Date(2014, 0 /* Jan */, 1))
+  })
+
+  it('accepts a timestamp', function() {
+    var result = subBusinessDays(new Date(2014, 8 /* Sep */, 1).getTime(), 10)
+    assert.deepEqual(result, new Date(2014, 7 /* Aug */, 18))
+  })
+
+  it('converts a fractional number to an integer', function() {
+    var result = subBusinessDays(new Date(2014, 8 /* Sep */, 1), 10.5)
+    assert.deepEqual(result, new Date(2014, 7 /* Aug */, 18))
+  })
+
+  it('implicitly converts number arguments', function() {
+    // $ExpectedMistake
+    var result = subBusinessDays(new Date(2014, 8 /* Sep */, 1), '10')
+    assert.deepEqual(result, new Date(2014, 7 /* Aug */, 18))
+  })
+
+  it('does not mutate the original date', function() {
+    var date = new Date(2014, 8 /* Sep */, 1)
+    subBusinessDays(date, 11)
+    assert.deepEqual(date, new Date(2014, 8 /* Sep */, 1))
+  })
+
+  it('returns `Invalid Date` if the given date is invalid', function() {
+    var result = subBusinessDays(new Date(NaN), 10)
+    assert(result instanceof Date && isNaN(result))
+  })
+
+  it('returns `Invalid Date` if the given amount is NaN', function() {
+    var result = subBusinessDays(new Date(2014, 8 /* Sep */, 1), NaN)
+    assert(result instanceof Date && isNaN(result))
+  })
+
+  it('throws TypeError exception if passed less than 2 arguments', function() {
+    assert.throws(subBusinessDays.bind(null), TypeError)
+    assert.throws(subBusinessDays.bind(null, 1), TypeError)
+  })
+})