[Date] Relative date badge (#2244)

Close #749

lib/text-formatters.js

@@ -109,6 +109,12 @@ function formatDate(d) {
   return dateString.replace(` ${moment().year()}`, '').toLowerCase()
 }
 
+function formatRelativeDate(timestamp) {
+  return moment()
+    .to(moment.unix(parseInt(timestamp, 10)))
+    .toLowerCase()
+}
+
 function renderTestResultMessage({
   passed,
   failed,
@@ -193,6 +199,7 @@ module.exports = {
   addv,
   maybePluralize,
   formatDate,
+  formatRelativeDate,
   renderTestResultMessage,
   renderTestResultBadge,
 }

lib/text-formatters.spec.js

@@ -11,6 +11,7 @@ const {
   addv,
   maybePluralize,
   formatDate,
+  formatRelativeDate,
   renderTestResultMessage,
   renderTestResultBadge,
 } = require('./text-formatters')
@@ -100,6 +101,28 @@ describe('Text formatters', function() {
     })
   })
 
+  context('in october', function() {
+    let clock
+    beforeEach(function() {
+      clock = sinon.useFakeTimers(new Date(2018, 9, 29).getTime())
+    })
+    afterEach(function() {
+      clock.restore()
+    })
+
+    test(formatRelativeDate, () => {
+      given(new Date(2018, 9, 31).getTime() / 1000)
+        .describe('when given the end of october')
+        .expect('in 2 days')
+    })
+
+    test(formatRelativeDate, () => {
+      given(new Date(2018, 9, 1).getTime() / 1000)
+        .describe('when given the beginning of october')
+        .expect('a month ago')
+    })
+  })
+
   function renderBothStyles(props) {
     const { message: standardMessage, color } = renderTestResultBadge(props)
     const compactMessage = renderTestResultMessage({