test(misc): write tests for the parsing of dates

README.md

@@ -23,7 +23,7 @@ I did my best to correctly add types for all of the supported endpoints. However
 Add using yarn or npm
 
 ```bash
-yarn add darkskyy-api
+yarn add darksky-api
 ```
 
 ## Usage
@@ -59,9 +59,9 @@ Either be a UNIX timestamp or a string formatted as follows:
 
 The library will try it's best to parse the Date string you pass in, so you don't _need_ to supply it in the above format. But for safety its probably best.
 
-Timezone should either be omitted (to refer to local time for the location being requested),
-`Z` (referring to GMT time), or +[HH][mm] or -[HH][mm] for an offset from GMT
-in hours and minutes.
+> Timezone should either be omitted (to refer to local time for the location being requested),
+> `Z` (referring to GMT time), or +[HH][mm] or -[HH][mm] for an offset from GMT
+> in hours and minutes.
 
 ## 1. DarkSky class
 

src/misc/util.ts

@@ -1,6 +1,7 @@
 import format from 'date-fns/format'
 import isDate from 'date-fns/is_date'
 import isValid from 'date-fns/is_valid'
+import parse from 'date-fns/parse'
 
 import { NumberString, TimeMachineRequest } from '../types'
 import { badRequest } from './errors'
@@ -16,8 +17,8 @@ export const DARKSKY_DATE_FORMAT = 'YYYY-MM-DDTHH:mm:ssZZ'
  * @param date Date string or object to format using [[DARKSKY_DATE_FORMAT]].
  */
 export function formatDateString(date: string | Date): string {
-  const target = isDate(date) ? (date as Date) : new Date(date)
-  if (!isValid(target)) {
+  const target: Date = isString(date) ? parse(date) : (date as Date)
+  if (!isDate(target) || !isValid(target)) {
     throw badRequest(`'${target}' is not a valid Date object.`)
   }
 
@@ -34,9 +35,10 @@ export function formatDateString(date: string | Date): string {
  */
 export function formatTimeMachineTime({ time }: TimeMachineRequest) {
   if (!time) return undefined
-  else if (Number.isInteger(time as number)) {
+  else if (isString(time) || isDate(time)) return formatDateString(time as string | Date)
+  else if (isNumber(time as number)) {
     return formatDateString(new Date((time as number) * 1000))
-  } else if (isString(time) || isDate(time)) return formatDateString(time as string | Date)
+  }
 }
 
 /**

test/misc/util.test.ts

@@ -0,0 +1,75 @@
+import format from 'date-fns/format'
+
+import {
+  DARKSKY_DATE_FORMAT,
+  formatDateString,
+  formatTimeMachineTime,
+  isNumber,
+  isString
+} from '../../src/misc/util'
+
+describe('Util', () => {
+  describe('isString', () => {
+    it('should return true on a valid string', () => {
+      expect(isString('I am a string')).toBeTruthy()
+    })
+
+    it('should return false on any other type', () => {
+      expect(isString(42)).toBeFalsy()
+      expect(isString({})).toBeFalsy()
+      expect(isString([42])).toBeFalsy()
+    })
+  })
+
+  describe('isNumber', () => {
+    it('should be true if it is a valid number', () => {
+      expect(isNumber(42)).toBeTruthy()
+      expect(isNumber(-42)).toBeTruthy()
+      expect(isNumber(42.24)).toBeTruthy()
+      expect(isNumber(-42.24)).toBeTruthy()
+    })
+
+    it('should parse a number string', () => {
+      expect(isNumber('42')).toBeTruthy()
+    })
+
+    it('should be false if passed an invalid number string', () => {
+      expect(isNumber('foo')).toBeFalsy()
+      expect(isNumber('')).toBeFalsy()
+    })
+  })
+
+  describe('formatTimeMachineTime', () => {
+    it('should handle an undefined time', () => {
+      expect(formatTimeMachineTime({} as any)).toBeUndefined()
+    })
+
+    it('should handle a UNIX timestamp', () => {
+      const expected = format(2222222 * 1000, DARKSKY_DATE_FORMAT)
+      const actual = formatTimeMachineTime({ time: 2222222 } as any)
+
+      expect(actual).toEqual(expected)
+    })
+
+    it('should handle a date object', () => {
+      const time = new Date()
+      const expected = format(time, DARKSKY_DATE_FORMAT)
+      const actual = formatTimeMachineTime({ time } as any)
+
+      expect(actual).toEqual(expected)
+    })
+
+    it('should handle a date string', () => {
+      const time = 'May 5 2019'
+      const expected = format(time, DARKSKY_DATE_FORMAT)
+      const actual = formatTimeMachineTime({ time } as any)
+
+      expect(actual).toEqual(expected)
+    })
+
+    it('should handle invalid type', () => {
+      expect(() => formatDateString({ time: 'imabaddate' } as any)).toThrow()
+      expect(formatTimeMachineTime({ time: { foo: 42 } } as any)).toBeUndefined()
+    })
+  })
+})