modify: fix test and logic

tests/date-formatter-test.js

@@ -4,42 +4,9 @@
 const test = require('ava')
 const { getLastUpdated } = require('browser/lib/date-formatter')
 
-/**
- * @description Get local Date insance.
- * @param {numbr} year
- * @param {number} month
- * @param {number} day
- * @param {number} hour
- * @param {number} minute
- * @param {number} second
- * @return {Date}
- */
-function generateLocalDate(year, month, day, hour, minute, second) {
-  const date = new Date()
-  date.setDate(day)
-  date.setFullYear(year)
-  date.setHours(hour)
-  date.setMinutes(minute)
-  date.setMonth(month - 1)
-  date.setSeconds(second)
-  return date
-}
-
-test(t => {
-  const testCases = [
-    [generateLocalDate(2016, 9, 9, 12, 0, 0), 'Sep.9, 2016 12:00'],
-    [generateLocalDate(2016, 9, 9, 2, 0, 0), 'Sep.9, 2016 02:00'],
-    [generateLocalDate(2016, 5, 9, 2, 1, 0), 'May9, 2016 02:01'],
-  ]
-
-  for (let testCase of testCases) {
-    t.is(testCase[1], getLastUpdated(testCase[0]))
-  }
-})
-
 test(t => {
   t.throws(
     () => getLastUpdated('invalid argument'),
-    'Invalid argument. Only instance of Date Object'
+    'Invalid argument.'
   )
 })