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backend/node_modules/date-fns/esm/addDays/index.d.ts

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+// This file is generated automatically by `scripts/build/typings.js`. Please, don't change it.
+
+import { addDays } from 'date-fns'
+export default addDays

backend/node_modules/date-fns/esm/addDays/index.js

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+import toInteger from "../_lib/toInteger/index.js";
+import toDate from "../toDate/index.js";
+import requiredArgs from "../_lib/requiredArgs/index.js";
+/**
+ * @name addDays
+ * @category Day Helpers
+ * @summary Add the specified number of days to the given date.
+ *
+ * @description
+ * Add the specified number of days to the given date.
+ *
+ * @param {Date|Number} date - the date to be changed
+ * @param {Number} amount - the amount of days to be added. 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 days added
+ * @throws {TypeError} - 2 arguments required
+ *
+ * @example
+ * // Add 10 days to 1 September 2014:
+ * const result = addDays(new Date(2014, 8, 1), 10)
+ * //=> Thu Sep 11 2014 00:00:00
+ */
+export default function addDays(dirtyDate, dirtyAmount) {
+  requiredArgs(2, arguments);
+  var date = toDate(dirtyDate);
+  var amount = toInteger(dirtyAmount);
+  if (isNaN(amount)) {
+    return new Date(NaN);
+  }
+  if (!amount) {
+    // If 0 days, no-op to avoid changing times in the hour before end of DST
+    return date;
+  }
+  date.setDate(date.getDate() + amount);
+  return date;
+}

backend/node_modules/date-fns/esm/addDays/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

backend/node_modules/date-fns/esm/addDays/package.json

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+{
+  "sideEffects": false,
+  "typings": "../../typings.d.ts"
+}