cleaning up year and month diffs

diff --git a/moment.js b/moment.js
index b45633ba8ff37e83826966242175ecd6709fc940..d61f753d87499a0e3c0e3bcfb583f99803de7377 100644 (file)
--- a/moment.js
+++ b/moment.js
@@ -1091,17 +1091,18 @@
         },
 
         diff : function (input, val, asFloat) {
-            var inputMoment = this._isUTC ? moment(input).utc() : moment(input).local(),
-                zoneDiff = (this.zone() - inputMoment.zone()) * 6e4,
-                diff = this._d - inputMoment._d - zoneDiff,
-                year = this.year() - inputMoment.year(),
-                month = this.month() - inputMoment.month(),
-                date = this.date() - inputMoment.date(),
+            var that = this._isUTC ? moment(input).utc() : moment(input).local(),
+                zoneDiff = (this.zone() - that.zone()) * 6e4,
+                diff = (this - that) - zoneDiff,
                 output;
-            if (val === 'months') {
-                output = year * 12 + month + date / 30;
-            } else if (val === 'years') {
-                output = year + (month + date / 30) / 12;
+
+            if (val === 'years' || val === 'months') {
+                output = ((this.year() - that.year()) * 12) + (this.month() - that.month());
+                output += (this - moment(this).startOf('month')) / (864e5 * this.daysInMonth());
+                output -= (that - moment(that).startOf('month')) / (864e5 * that.daysInMonth());
+                if (val === 'years') {
+                    output = output / 12;
+                }
             } else {
                 output = val === 'seconds' ? diff / 1e3 : // 1000
                     val === 'minutes' ? diff / 6e4 : // 1000 * 60
@@ -1211,7 +1212,7 @@
         },
 
         dayOfYear : function (input) {
-            var dayOfYear = moment(this).startOf('day').diff(moment(this).startOf('year'), 'days') + 1;
+            var dayOfYear = round((moment(this).startOf('day') - moment(this).startOf('year')) / 864e5) + 1;
             return input == null ? dayOfYear : this.add("d", (input - dayOfYear));
         },
 

diff --git a/test/moment/diff.js b/test/moment/diff.js
index b1fc352fa5949eaa2006de2f7cc57d47efb90f71..f2f55037d8cf66836126f6bfc08b6ecd780f7796 100644 (file)
--- a/test/moment/diff.js
+++ b/test/moment/diff.js
@@ -1,5 +1,9 @@
 var moment = require("../../moment");
 
+function equal(test, a, b, message) {
+    test.ok(Math.abs(a - b) < 0.000001, message);
+}
+
 exports.diff = {
     "diff" : function(test) {
         test.expect(5);
@@ -16,10 +20,9 @@ exports.diff = {
     },
 
     "diff key after" : function(test) {
-        test.expect(9);
+        test.expect(8);
 
         test.equal(moment([2010]).diff([2011], 'years'), -1, "year diff");
-        test.equal(moment([2010]).diff([2011, 6], 'years', true), -1.5, "year diff, float");
         test.equal(moment([2010]).diff([2010, 2], 'months'), -2, "month diff");
         test.equal(moment([2010]).diff([2010, 0, 7], 'weeks'), -1, "week diff");
         test.equal(moment([2010]).diff([2010, 0, 21], 'weeks'), -3, "week diff");
@@ -31,10 +34,9 @@ exports.diff = {
     },
 
     "diff key before" : function(test) {
-        test.expect(9);
+        test.expect(8);
 
         test.equal(moment([2011]).diff([2010], 'years'), 1, "year diff");
-        test.equal(moment([2011, 6]).diff([2010], 'years', true), 1.5, "year diff, float");
         test.equal(moment([2010, 2]).diff([2010], 'months'), 2, "month diff");
         test.equal(moment([2010, 0, 4]).diff([2010], 'days'), 3, "day diff");
         test.equal(moment([2010, 0, 7]).diff([2010], 'weeks'), 1, "week diff");
@@ -89,6 +91,46 @@ exports.diff = {
 
         test.ok(moment([2012, 1, 19]).diff(moment([2002, 1, 20]), 'years', true) < 10, "year diff should include date of month");
 
+        test.done();
+    },
+
+    "year diffs" : function (test) {
+        test.expect(8);
+
+        var elevenMonthsThirtyDays = (11 + 30/31) / 12,
+            thirtyDays = (30/31) / 12,
+            elevenMonthsThirtyHalfDays = (11 + 30.5/31) / 12,
+            thirtyHalfDays = (30.5/31) / 12;
+
+        equal(test, moment([2012, 0, 1]).diff([2012, 11, 31], 'years', true), -elevenMonthsThirtyDays, 'start to end of a leap year');
+        equal(test, moment([2012, 0, 1]).diff([2012, 0, 31], 'years', true), -thirtyDays, '30 days in a leap year');
+        equal(test, moment([2011, 0, 1]).diff([2011, 11, 31], 'years', true), -elevenMonthsThirtyDays, 'start to end of a non-leap year');
+        equal(test, moment([2011, 0, 1]).diff([2011, 0, 31], 'years', true), -thirtyDays, '30 days in a non-leap year');
+        equal(test, moment([2011, 0, 1]).diff([2011, 11, 31, 12], 'years', true), -elevenMonthsThirtyHalfDays, 'start to end of a non-leap year');
+        equal(test, moment([2011, 0, 1]).diff([2011, 0, 31, 12], 'years', true), -thirtyHalfDays, '30.5 days in a non-leap year');
+        equal(test, moment([2011, 0, 1]).diff([2012, 11, 31, 12], 'years', true), -(1 + elevenMonthsThirtyHalfDays), 'spanning two years');
+        equal(test, moment([2011, 0, 1]).diff([2012, 0, 31, 12], 'years', true), -(1 + thirtyHalfDays), '1 year 30.5 days spanning two years');
+
+        test.done();
+    },
+
+    "year diff over new year" : function (test) {
+        test.expect(2);
+
+        equal(test, moment([2011, 11, 31]).diff([2012, 11, 31], 'years', true), -1, '1 year difference over the new year should correct');
+        equal(test, moment([2011, 11, 31]).diff([2012, 0, 1], 'years', true), -(1/31) / 12, '1 day difference over the new year should correct');
+
+        test.done();
+    },
+
+    "month diffs" : function (test) {
+        test.expect(4);
+
+        equal(test, moment([2012, 0, 1]).diff([2012, 11, 31], 'months', true), -(11 + 30 / 31), '11 month 30 day diff should be 11+30/31 months');
+        equal(test, moment([2012, 0, 1]).diff([2012, 0, 31], 'months', true), -30 / 31, '30 day diff should be 30/31 months');
+        equal(test, moment([2012, 0, 1]).diff([2012, 11, 31, 12], 'months', true), -(11 + 30.5 / 31), '11 month 30.5 day diff should be 11+30.5/31 months');
+        equal(test, moment([2012, 0, 1]).diff([2012, 0, 31, 12], 'months', true), -30.5 / 31, '30.5 day diff should be 30.5/31 months');
+
         test.done();
     }
 };