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diff --git a/date-fns/src/eachHourOfInterval/index.ts b/date-fns/src/eachHourOfInterval/index.ts
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+import addHours from '../addHours/index'
+import toDate from '../toDate/index'
+import requiredArgs from '../_lib/requiredArgs/index'
+import { Interval, StepOptions } from '../types'
+
+/**
+ * @name eachHourOfInterval
+ * @category Interval Helpers
+ * @summary Return the array of hours within the specified time interval.
+ *
+ * @description
+ * Return the array of hours within the specified time interval.
+ *
+ * @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 hours from the hour of the interval start to the hour 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 hour between 6 October 2014, 12:00 and 6 October 2014, 15:00
+ * var result = eachHourOfInterval({
+ *   start: new Date(2014, 9, 6, 12),
+ *   end: new Date(2014, 9, 6, 15)
+ * })
+ * //=> [
+ * //   Mon Oct 06 2014 12:00:00,
+ * //   Mon Oct 06 2014 13:00:00,
+ * //   Mon Oct 06 2014 14:00:00,
+ * //   Mon Oct 06 2014 15:00:00
+ * // ]
+ */
+export default function eachHourOfInterval(
+  dirtyInterval: Interval,
+  options?: StepOptions
+): Date[] {
+  requiredArgs(1, arguments)
+
+  const interval = dirtyInterval || {}
+  const startDate = toDate(interval.start)
+  const endDate = toDate(interval.end)
+
+  const startTime = startDate.getTime()
+  const endTime = endDate.getTime()
+
+  // Throw an exception if start date is after end date or if any date is `Invalid Date`
+  if (!(startTime <= endTime)) {
+    throw new RangeError('Invalid interval')
+  }
+
+  const dates = []
+
+  let currentDate = startDate
+  currentDate.setMinutes(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 = addHours(currentDate, step)
+  }
+
+  return dates
+}