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+import getQuarter from '../getQuarter/index'
+import toDate from '../toDate/index'
+import requiredArgs from '../_lib/requiredArgs/index'
+
+/**
+ * @name differenceInCalendarQuarters
+ * @category Quarter Helpers
+ * @summary Get the number of calendar quarters between the given dates.
+ *
+ * @description
+ * Get the number of calendar quarters between the given dates.
+ *
+ * ### 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).
+ *
+ * @param {Date|Number} dateLeft - the later date
+ * @param {Date|Number} dateRight - the earlier date
+ * @returns {Number} the number of calendar quarters
+ * @throws {TypeError} 2 arguments required
+ *
+ * @example
+ * // How many calendar quarters are between 31 December 2013 and 2 July 2014?
+ * var result = differenceInCalendarQuarters(
+ *   new Date(2014, 6, 2),
+ *   new Date(2013, 11, 31)
+ * )
+ * //=> 3
+ */
+export default function differenceInCalendarQuarters(
+  dirtyDateLeft: Date | number,
+  dirtyDateRight: Date | number
+): number {
+  requiredArgs(2, arguments)
+
+  const dateLeft = toDate(dirtyDateLeft)
+  const dateRight = toDate(dirtyDateRight)
+
+  const yearDiff = dateLeft.getFullYear() - dateRight.getFullYear()
+  const quarterDiff = getQuarter(dateLeft) - getQuarter(dateRight)
+
+  return yearDiff * 4 + quarterDiff
+}