Merge pull request #3247 from hypothesis/change-display-of-datetimes-on-annotations

Change display of datetimes on annotations

h/static/scripts/test/time-test.js

@@ -9,19 +9,20 @@ var month = day * 30;
 var year = day * 365;
 
 var FIXTURES_TO_FUZZY_STRING = [
-  [10, 'moments ago'],
-  [29, 'moments ago'],
-  [49, '49 seconds ago'],
-  [minute + 5, 'a minute ago'],
-  [3 * minute + 5, '3 minutes ago'],
-  [4 * hour, '4 hours ago'],
-  [27 * hour, 'a day ago'],
-  [3 * day + 30 * minute, '3 days ago'],
-  [6 * month + 2 * day, '6 months ago'],
-  [1 * year, 'one year ago'],
-  [1 * year + 2 * month, 'one year ago'],
-  [2 * year, '2 years ago'],
-  [8 * year, '8 years ago']
+  [10, 'Just now'],
+  [29, 'Just now'],
+  [49, '49 secs'],
+  [minute + 5, '1 min'],
+  [3 * minute + 5, '3 mins'],
+  [hour, '1 hr'],
+  [4 * hour, '4 hrs'],
+  [27 * hour, '1 Jan'],
+  [3 * day + 30 * minute, '1 Jan'],
+  [6 * month + 2 * day, '1 Jan'],
+  [1 * year, '1 Jan 1970'],
+  [1 * year + 2 * month, '1 Jan 1970'],
+  [2 * year, '1 Jan 1970'],
+  [8 * year, '1 Jan 1970']
 ];
 
 var FIXTURES_NEXT_FUZZY_UPDATE = [
@@ -31,10 +32,10 @@ var FIXTURES_NEXT_FUZZY_UPDATE = [
   [minute + 5, minute],
   [3 * minute + 5, minute],
   [4 * hour, hour],
-  [27 * hour, day],
-  [3 * day + 30 * minute, day],
-  [6 * month + 2 * day, 24 * day], // longer times are not supported
-  [8 * year, 24 * day]            // by setTimout
+  [27 * hour, null],
+  [3 * day + 30 * minute, null],
+  [6 * month + 2 * day, null],
+  [8 * year, null]
 ];
 
 describe('time', function () {
@@ -50,18 +51,35 @@ describe('time', function () {
   });
 
   describe('.toFuzzyString', function () {
+
+    function mockIntl() {
+      return {
+        DateTimeFormat: function () {
+          return {
+            format: function () {
+              if (new Date().getYear() === 70) {
+                return '1 Jan';
+              } else {
+                return '1 Jan 1970';
+              }
+            }
+          };
+        }
+      };
+    }
+
     it('Handles empty dates', function () {
       var t = null;
       var expect = '';
-      assert.equal(time.toFuzzyString(t), expect);
+      assert.equal(time.toFuzzyString(t, mockIntl()), expect);
     });
 
     var testFixture = function (f) {
       return function () {
-        var t = new Date();
+        var t = new Date().toISOString();
         var expect = f[1];
         sandbox.clock.tick(f[0] * 1000);
-        assert.equal(time.toFuzzyString(t), expect);
+        assert.equal(time.toFuzzyString(t, mockIntl()), expect);
       };
     };
 
@@ -70,6 +88,25 @@ describe('time', function () {
       it('creates correct fuzzy string for fixture ' + i,
         testFixture(f));
     }
+
+    it('falls back to simple strings for >24hrs ago', function () {
+      // If window.Intl is not available then the date formatting for dates
+      // more than one day ago falls back to a simple date string.
+      var d = new Date().toISOString();
+      sandbox.clock.tick(day * 2 * 1000);
+
+      assert.equal(time.toFuzzyString(d, null), 'Thu Jan 01 1970');
+    });
+
+    it('falls back to simple strings for >1yr ago', function () {
+      // If window.Intl is not available then the date formatting for dates
+      // more than one year ago falls back to a simple date string.
+      var d = new Date().toISOString();
+      sandbox.clock.tick(year * 2 * 1000);
+
+      assert.equal(time.toFuzzyString(d, null), 'Thu Jan 01 1970');
+    });
+
   });
 
   describe('.decayingInterval', function () {
@@ -105,6 +142,18 @@ describe('time', function () {
       sandbox.clock.tick(minute * 1000);
       assert.notCalled(callback);
     });
+
+    it('does not set a timeout for dates > 24hrs ago', function () {
+      var date = new Date();
+      var ONE_DAY = day * 1000;
+      sandbox.clock.tick(10 * ONE_DAY);
+      var callback = sandbox.stub();
+
+      time.decayingInterval(date, callback);
+      sandbox.clock.tick(ONE_DAY * 2);
+
+      assert.notCalled(callback);
+    });
   });
 
   describe('.nextFuzzyUpdate', function () {
@@ -116,7 +165,7 @@ describe('time', function () {
 
     var testFixture = function (f) {
       return function () {
-        var t = new Date();
+        var t = new Date().toISOString();
         var expect = f[1];
         sandbox.clock.tick(f[0] * 1000);
         assert.equal(time.nextFuzzyUpdate(t), expect);

h/static/scripts/time.js

@@ -2,39 +2,148 @@
 
 var minute = 60;
 var hour = minute * 60;
-var day = hour * 24;
-var month = day * 30;
-var year = day * 365;
+
+function lessThanThirtySecondsAgo(date, now) {
+  return ((now - date) < 30 * 1000);
+}
+
+function lessThanOneMinuteAgo(date, now) {
+  return ((now - date) < 60 * 1000);
+}
+
+function lessThanOneHourAgo(date, now) {
+  return ((now - date) < (60 * 60 * 1000));
+}
+
+function lessThanOneDayAgo(date, now) {
+  return ((now - date) < (24 * 60 * 60 * 1000));
+}
+
+function thisYear(date, now) {
+  return date.getFullYear() === now.getFullYear();
+}
+
+function delta(date, now) {
+  return Math.round((now - date) / 1000);
+}
+
+function nSec(date, now) {
+  return '{} secs'.replace('{}', Math.floor(delta(date, now)));
+}
+
+function nMin(date, now) {
+  var n = Math.floor(delta(date, now) / minute);
+  var template = '{} min';
+
+  if (n > 1) {
+    template = template + 's';
+  }
+
+  return template.replace('{}', n);
+}
+
+function nHr(date, now) {
+  var n = Math.floor(delta(date, now) / hour);
+  var template = '{} hr';
+
+  if (n > 1) {
+    template = template + 's';
+  }
+
+  return template.replace('{}', n);
+}
+
+// Cached DateTimeFormat instances,
+// because instantiating a DateTimeFormat is expensive.
+var formatters = {};
+
+/**
+ * Efficiently return `date` formatted with `options`.
+ *
+ * This is a wrapper for Intl.DateTimeFormat.format() that caches
+ * DateTimeFormat instances because they're expensive to create.
+ * Calling Date.toLocaleDateString() lots of times is also expensive in some
+ * browsers as it appears to create a new formatter for each call.
+ *
+ * @returns {string}
+ *
+ */
+function format(date, options, Intl) {
+  // If the tests have passed in a mock Intl then use it, otherwise use the
+  // real one.
+  if (typeof Intl === 'undefined') {
+    Intl = window.Intl;
+  }
+
+  if (Intl && Intl.DateTimeFormat) {
+    var key = JSON.stringify(options);
+    var formatter = formatters[key];
+
+    if (!formatter) {
+      formatter = formatters[key] = new Intl.DateTimeFormat(undefined,
+                                                            options);
+    }
+
+    return formatter.format(date);
+  } else {
+    // IE < 11, Safari <= 9.0.
+    return date.toDateString();
+  }
+}
+
+function dayAndMonth(date, now, Intl) {
+  return format(date, {month: 'short', day: 'numeric'}, Intl);
+}
+
+function dayAndMonthAndYear(date, now, Intl) {
+  return format(date, {day: 'numeric', month: 'short', year: 'numeric'}, Intl);
+}
 
 var BREAKPOINTS = [
-  [30,         'moments ago',    1],
-  [minute,     '{} seconds ago', 1],
-  [2 * minute, 'a minute ago',   minute],
-  [hour,       '{} minutes ago', minute],
-  [2 * hour,   'an hour ago',    hour],
-  [day,        '{} hours ago',   hour],
-  [2 * day,    'a day ago',      day],
-  [month,      '{} days ago',    day],
-  [year,       '{} months ago',  month],
-  [2 * year,   'one year ago',   year],
-  [Infinity,   '{} years ago',   year]
+  {
+    test: lessThanThirtySecondsAgo,
+    format: function () {return 'Just now';},
+    nextUpdate: 1
+  },
+  {
+    test: lessThanOneMinuteAgo,
+    format: nSec,
+    nextUpdate: 1
+  },
+  {
+    test: lessThanOneHourAgo,
+    format: nMin,
+    nextUpdate: minute
+  },
+  {
+    test: lessThanOneDayAgo,
+    format: nHr,
+    nextUpdate: hour
+  },
+  {
+    test: thisYear,
+    format: dayAndMonth,
+    nextUpdate: null
+  },
+  {
+    test: function () {return true;},
+    format: dayAndMonthAndYear,
+    nextUpdate: null
+  }
 ];
 
-function getBreakpoint(date) {
-  var delta = Math.round((new Date() - new Date(date)) / 1000);
-  var breakpoint;
+function getBreakpoint(date, now) {
+
+  // Turn the given ISO 8601 string into a Date object.
+  date = new Date(date);
 
+  var breakpoint;
   for (var i = 0; i < BREAKPOINTS.length; i++) {
-    if (BREAKPOINTS[i][0] > delta) {
-      breakpoint = BREAKPOINTS[i];
-      break;
+    breakpoint = BREAKPOINTS[i];
+    if (breakpoint.test(date, now)) {
+      return breakpoint;
     }
   }
-
-  return {
-    delta: delta,
-    breakpoint: breakpoint,
-  };
 }
 
 function nextFuzzyUpdate(date) {
@@ -42,13 +151,12 @@ function nextFuzzyUpdate(date) {
     return null;
   }
 
-  var breakpoint = getBreakpoint(date).breakpoint;
-  if (!breakpoint) {
+  var secs = getBreakpoint(date, new Date()).nextUpdate;
+
+  if (secs === null) {
     return null;
   }
 
-  var secs = breakpoint[2];
-
   // We don't want to refresh anything more often than 5 seconds
   secs = Math.max(secs, 5);
 
@@ -73,6 +181,9 @@ function decayingInterval(date, callback) {
   var timer;
   var update = function () {
     var fuzzyUpdate = nextFuzzyUpdate(date);
+    if (fuzzyUpdate === null) {
+      return;
+    }
     var nextUpdate = (1000 * fuzzyUpdate) + 500;
     timer = setTimeout(function () {
       callback(date);
@@ -92,19 +203,13 @@ function decayingInterval(date, callback) {
  * @param {number} date - The absolute timestamp to format.
  * @return {string} A 'fuzzy' string describing the relative age of the date.
  */
-function toFuzzyString(date) {
+function toFuzzyString(date, Intl) {
   if (!date) {
     return '';
   }
-  var breakpointInfo = getBreakpoint(date);
-  var breakpoint = breakpointInfo.breakpoint;
-  var delta = breakpointInfo.delta;
-  if (!breakpoint) {
-    return '';
-  }
-  var template = breakpoint[1];
-  var resolution = breakpoint[2];
-  return template.replace('{}', String(Math.floor(delta / resolution)));
+  var now = new Date();
+
+  return getBreakpoint(date, now).format(new Date(date), now, Intl);
 }
 
 module.exports = {