5 files changed, 312 insertions, 0 deletions
diff --git a/date-fns/src/eachDayOfInterval/benchmark.js b/date-fns/src/eachDayOfInterval/benchmark.js
new file mode 100644
index 0000000..45d8e44
--- /dev/null
+++ b/date-fns/src/eachDayOfInterval/benchmark.js
@@ -0,0 +1,16 @@
+// @flow
+/* eslint-env mocha */
+/* global suite, benchmark */
+
+import eachDayOfInterval from '.'
+
+suite('eachDayOfInterval', function () {
+  benchmark('date-fns', function () {
+    return eachDayOfInterval({start: this.dateA, end: this.dateB})
+  })
+}, {
+  setup: function () {
+    this.dateA = new Date()
+    this.dateB = new Date(this.dateA.getTime() + 604800000)
+  }
+})
diff --git a/date-fns/src/eachDayOfInterval/index.d.ts b/date-fns/src/eachDayOfInterval/index.d.ts
new file mode 100644
index 0000000..80fc0dc
--- /dev/null
+++ b/date-fns/src/eachDayOfInterval/index.d.ts
@@ -0,0 +1,4 @@
+// This file is generated automatically by `scripts/build/typings.js`. Please, don't change it.
+
+import { eachDayOfInterval } from 'date-fns'
+export default eachDayOfInterval
diff --git a/date-fns/src/eachDayOfInterval/index.js.flow b/date-fns/src/eachDayOfInterval/index.js.flow
new file mode 100644
index 0000000..5a9b8e4
--- /dev/null
+++ b/date-fns/src/eachDayOfInterval/index.js.flow
@@ -0,0 +1,57 @@
+// @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: (
+  interval: Interval,
+  options?: {
+    step?: number,
+  }
+) => Date[]
diff --git a/date-fns/src/eachDayOfInterval/index.ts b/date-fns/src/eachDayOfInterval/index.ts
new file mode 100644
index 0000000..fded968
--- /dev/null
+++ b/date-fns/src/eachDayOfInterval/index.ts
@@ -0,0 +1,98 @@
+import toDate from '../toDate/index'
+import requiredArgs from '../_lib/requiredArgs/index'
+
+/**
+ * @name eachDayOfInterval
+ * @category Interval Helpers
+ * @summary Return the array of dates within the specified time interval.
+ *
+ * @description
+ * Return the array of dates within the specified time interval.
+ *
+ * ### v2.0.0 breaking changes:
+ *
+ * - [Changes that are common for the whole library](https://github.com/date-fns/date-fns/blob/master/docs/upgradeGuide.md#Common-Changes).
+ *
+ * - The function was renamed from `eachDay` to `eachDayOfInterval`.
+ *   This change was made to mirror the use of the word "interval" in standard ISO 8601:2004 terminology:
+ *
+ *   ```
+ *   2.1.3
+ *   time interval
+ *   part of the time axis limited by two instants
+ *   ```
+ *
+ *   Also, this function now accepts an object with `start` and `end` properties
+ *   instead of two arguments as an interval.
+ *   This function now throws `RangeError` if the start of the interval is after its end
+ *   or if any date in the interval is `Invalid Date`.
+ *
+ *   ```javascript
+ *   // Before v2.0.0
+ *
+ *   eachDay(new Date(2014, 0, 10), new Date(2014, 0, 20))
+ *
+ *   // v2.0.0 onward
+ *
+ *   eachDayOfInterval(
+ *     { start: new Date(2014, 0, 10), end: new Date(2014, 0, 20) }
+ *   )
+ *   ```
+ *
+ * @param {Interval} interval - the interval. See [Interval]{@link https://date-fns.org/docs/Interval}
+ * @param {Object} [options] - an object with options.
+ * @param {Number} [options.step=1] - the step to increment by. The value should be more than 1.
+ * @returns {Date[]} the array with starts of days from the day of the interval start to the day of the interval end
+ * @throws {TypeError} 1 argument required
+ * @throws {RangeError} `options.step` must be a number greater than 1
+ * @throws {RangeError} The start of an interval cannot be after its end
+ * @throws {RangeError} Date in interval cannot be `Invalid Date`
+ *
+ * @example
+ * // Each day between 6 October 2014 and 10 October 2014:
+ * const result = eachDayOfInterval({
+ *   start: new Date(2014, 9, 6),
+ *   end: new Date(2014, 9, 10)
+ * })
+ * //=> [
+ * //   Mon Oct 06 2014 00:00:00,
+ * //   Tue Oct 07 2014 00:00:00,
+ * //   Wed Oct 08 2014 00:00:00,
+ * //   Thu Oct 09 2014 00:00:00,
+ * //   Fri Oct 10 2014 00:00:00
+ * // ]
+ */
+export default function eachDayOfInterval(
+  dirtyInterval: Interval,
+  options?: { step?: number }
+): Date[] {
+  requiredArgs(1, arguments)
+
+  const interval = dirtyInterval || {}
+  const startDate = toDate(interval.start)
+  const endDate = toDate(interval.end)
+
+  const endTime = endDate.getTime()
+
+  // Throw an exception if start date is after end date or if any date is `Invalid Date`
+  if (!(startDate.getTime() <= endTime)) {
+    throw new RangeError('Invalid interval')
+  }
+
+  const dates = []
+
+  const currentDate = startDate
+  currentDate.setHours(0, 0, 0, 0)
+
+  const step = options && 'step' in options ? Number(options.step) : 1
+  if (step < 1 || isNaN(step))
+    throw new RangeError('`options.step` must be a number greater than 1')
+
+  while (currentDate.getTime() <= endTime) {
+    dates.push(toDate(currentDate))
+    currentDate.setDate(currentDate.getDate() + step)
+    currentDate.setHours(0, 0, 0, 0)
+  }
+
+  return dates
+}
diff --git a/date-fns/src/eachDayOfInterval/test.ts b/date-fns/src/eachDayOfInterval/test.ts
new file mode 100644
index 0000000..2ace8e1
--- /dev/null
+++ b/date-fns/src/eachDayOfInterval/test.ts
@@ -0,0 +1,137 @@
+// @flow
+/* eslint-env mocha */
+
+import assert from 'assert'
+import eachDayOfInterval from '.'
+
+describe('eachDayOfInterval', () => {
+  it('returns an array with starts of days from the day of the start date to the day of the end date', () => {
+    const result = eachDayOfInterval({
+      start: new Date(2014, 9 /* Oct */, 6),
+      end: new Date(2014, 9 /* Oct */, 12)
+    })
+    assert.deepStrictEqual(result, [
+      new Date(2014, 9 /* Oct */, 6),
+      new Date(2014, 9 /* Oct */, 7),
+      new Date(2014, 9 /* Oct */, 8),
+      new Date(2014, 9 /* Oct */, 9),
+      new Date(2014, 9 /* Oct */, 10),
+      new Date(2014, 9 /* Oct */, 11),
+      new Date(2014, 9 /* Oct */, 12)
+    ])
+  })
+
+  it('accepts timestamps', () => {
+    const result = eachDayOfInterval({
+      start: new Date(2014, 9 /* Oct */, 6).getTime(),
+      end: new Date(2014, 9 /* Oct */, 12).getTime()
+    })
+    assert.deepStrictEqual(result, [
+      new Date(2014, 9 /* Oct */, 6),
+      new Date(2014, 9 /* Oct */, 7),
+      new Date(2014, 9 /* Oct */, 8),
+      new Date(2014, 9 /* Oct */, 9),
+      new Date(2014, 9 /* Oct */, 10),
+      new Date(2014, 9 /* Oct */, 11),
+      new Date(2014, 9 /* Oct */, 12)
+    ])
+  })
+
+  it('handles the dates that are not starts of days', () => {
+    const result = eachDayOfInterval({
+      start: new Date(2014, 9 /* Oct */, 6, 6, 35),
+      end: new Date(2014, 9 /* Oct */, 12, 22, 15)
+    })
+    assert.deepStrictEqual(result, [
+      new Date(2014, 9 /* Oct */, 6),
+      new Date(2014, 9 /* Oct */, 7),
+      new Date(2014, 9 /* Oct */, 8),
+      new Date(2014, 9 /* Oct */, 9),
+      new Date(2014, 9 /* Oct */, 10),
+      new Date(2014, 9 /* Oct */, 11),
+      new Date(2014, 9 /* Oct */, 12)
+    ])
+  })
+
+  it('returns one day if the both arguments are on the same day', () => {
+    const result = eachDayOfInterval({
+      start: new Date(2014, 9 /* Oct */, 6, 14),
+      end: new Date(2014, 9 /* Oct */, 6, 15)
+    })
+    assert.deepStrictEqual(result, [new Date(2014, 9 /* Oct */, 6)])
+  })
+
+  it('returns one day if the both arguments are the same', () => {
+    const result = eachDayOfInterval({
+      start: new Date(2014, 9 /* Oct */, 6, 14),
+      end: new Date(2014, 9 /* Oct */, 6, 14)
+    })
+    assert.deepStrictEqual(result, [new Date(2014, 9 /* Oct */, 6)])
+  })
+
+  it('throws an exception if the start date is after the end date', () => {
+    const block = eachDayOfInterval.bind(null, {
+      start: new Date(2014, 9 /* Oct */, 12),
+      end: new Date(2014, 9 /* Oct */, 6)
+    })
+    assert.throws(block, RangeError)
+  })
+
+  it('throws an exception if the start date is `Invalid Date`', () => {
+    var block = eachDayOfInterval.bind(null, {
+      start: new Date(NaN),
+      end: new Date(2014, 9 /* Oct */, 6)
+    })
+    assert.throws(block, RangeError)
+  })
+
+  it('throws an exception if the end date is `Invalid Date`', () => {
+    var block = eachDayOfInterval.bind(null, {
+      start: new Date(2014, 9 /* Oct */, 12),
+      end: new Date(NaN)
+    })
+    assert.throws(block, RangeError)
+  })
+
+  it('throws an exception if the interval is undefined', () => {
+    var block = eachDayOfInterval.bind(
+      null,
+      //@ts-expect-error
+      undefined
+    )
+    assert.throws(block, RangeError)
+  })
+
+  it('throws TypeError exception if passed less than 1 argument', () => {
+    assert.throws(eachDayOfInterval.bind(null), TypeError)
+  })
+
+  describe('options.step', () => {
+    const interval = {
+      start: new Date(2014, 9 /* Oct */, 6),
+      end: new Date(2014, 9 /* Oct */, 13)
+    }
+
+    const stepError = /^RangeError: `options.step` must be a number greater than 1$/
+
+    it('returns an array with starts of days from the day of the start date to the day of the end date with the given step', () => {
+      const result = eachDayOfInterval(interval, { step: 3 })
+      assert.deepStrictEqual(result, [
+        new Date(2014, 9 /* Oct */, 6),
+        new Date(2014, 9 /* Oct */, 9),
+        new Date(2014, 9 /* Oct */, 12)
+      ])
+    })
+
+    it('throws TypeError error if `options.step` is less than 1', () => {
+      assert.throws(() => eachDayOfInterval(interval, { step: 0 }), stepError)
+      assert.throws(() => eachDayOfInterval(interval, { step: -3 }), stepError)
+    })
+
+    it('throws TypeError error if `options.step` is NaN', () => {
+      //@ts-expect-error
+      assert.throws(() => eachDayOfInterval(interval, { step: 'w' }), stepError)
+      assert.throws(() => eachDayOfInterval(interval, { step: NaN }), stepError)
+    })
+  })
+})