[bugfix] Fix startOf/endOf DST issues while boosting performance (#4338)

* Fix startOf/endOf DST issues

* Performance improvements

* Rewrite for legibility

* Fix for years in range 0-99

* Remove placeholder comments

* Revert comment

* Remove useless special-case

* Code review change: use break consistenly

* Rename per code review

* Fix typo

* Inline variable to end naming debate

* Address review comments

diff --git a/src/lib/create/date-from-array.js b/src/lib/create/date-from-array.js
index 59b57b0365c2160cd7f108fd77a5b253d7bb8d86..7fabbc05f183b96bbbee3a7dafea6c67dd3d8c2d 100644 (file)
--- a/src/lib/create/date-from-array.js
+++ b/src/lib/create/date-from-array.js
@@ -1,21 +1,35 @@
 export function createDate (y, m, d, h, M, s, ms) {
     // can't just apply() to create a date:
     // https://stackoverflow.com/q/181348
-    var date = new Date(y, m, d, h, M, s, ms);
-
+    var date;
     // the date constructor remaps years 0-99 to 1900-1999
-    if (y < 100 && y >= 0 && isFinite(date.getFullYear())) {
-        date.setFullYear(y);
+    if (y < 100 && y >= 0) {
+        // preserve leap years using a full 400 year cycle, then reset
+        date = new Date(y + 400, m, d, h, M, s, ms);
+        if (isFinite(date.getFullYear())) {
+            date.setFullYear(y);
+        }
+    } else {
+        date = new Date(y, m, d, h, M, s, ms);
     }
+
     return date;
 }
 
 export function createUTCDate (y) {
-    var date = new Date(Date.UTC.apply(null, arguments));
-
+    var date;
     // the Date.UTC function remaps years 0-99 to 1900-1999
-    if (y < 100 && y >= 0 && isFinite(date.getUTCFullYear())) {
-        date.setUTCFullYear(y);
+    if (y < 100 && y >= 0) {
+        var args = Array.prototype.slice.call(arguments);
+        // preserve leap years using a full 400 year cycle, then reset
+        args[0] = y + 400;
+        date = new Date(Date.UTC.apply(null, args));
+        if (isFinite(date.getUTCFullYear())) {
+            date.setUTCFullYear(y);
+        }
+    } else {
+        date = new Date(Date.UTC.apply(null, arguments));
     }
+
     return date;
 }

diff --git a/src/lib/moment/start-end-of.js b/src/lib/moment/start-end-of.js
index 02f982479ad8959af97b4ea99812c110c95e3d98..42c19cbc3b7e9597722c277105acebbad41f314e 100644 (file)
--- a/src/lib/moment/start-end-of.js
+++ b/src/lib/moment/start-end-of.js
@@ -1,59 +1,128 @@
 import { normalizeUnits } from '../units/aliases';
+import { hooks } from '../utils/hooks';
+
+var MS_PER_SECOND = 1000;
+var MS_PER_MINUTE = 60 * MS_PER_SECOND;
+var MS_PER_HOUR = 60 * MS_PER_MINUTE;
+var MS_PER_400_YEARS = (365 * 400 + 97) * 24 * MS_PER_HOUR;
+
+// actual modulo - handles negative numbers (for dates before 1970):
+function mod(dividend, divisor) {
+    return (dividend % divisor + divisor) % divisor;
+}
+
+function localStartOfDate(y, m, d) {
+    // the date constructor remaps years 0-99 to 1900-1999
+    if (y < 100 && y >= 0) {
+        // preserve leap years using a full 400 year cycle, then reset
+        return new Date(y + 400, m, d) - MS_PER_400_YEARS;
+    } else {
+        return new Date(y, m, d).valueOf();
+    }
+}
+
+function utcStartOfDate(y, m, d) {
+    // Date.UTC remaps years 0-99 to 1900-1999
+    if (y < 100 && y >= 0) {
+        // preserve leap years using a full 400 year cycle, then reset
+        return Date.UTC(y + 400, m, d) - MS_PER_400_YEARS;
+    } else {
+        return Date.UTC(y, m, d);
+    }
+}
 
 export function startOf (units) {
+    var time;
     units = normalizeUnits(units);
-    // the following switch intentionally omits break keywords
-    // to utilize falling through the cases.
+    if (units === undefined || units === 'millisecond' || !this.isValid()) {
+        return this;
+    }
+
+    var startOfDate = this._isUTC ? utcStartOfDate : localStartOfDate;
+
     switch (units) {
         case 'year':
-            this.month(0);
-            /* falls through */
+            time = startOfDate(this.year(), 0, 1);
+            break;
         case 'quarter':
+            time = startOfDate(this.year(), this.month() - this.month() % 3, 1);
+            break;
         case 'month':
-            this.date(1);
-            /* falls through */
+            time = startOfDate(this.year(), this.month(), 1);
+            break;
         case 'week':
+            time = startOfDate(this.year(), this.month(), this.date() - this.weekday());
+            break;
         case 'isoWeek':
+            time = startOfDate(this.year(), this.month(), this.date() - (this.isoWeekday() - 1));
+            break;
         case 'day':
         case 'date':
-            this.hours(0);
-            /* falls through */
+            time = startOfDate(this.year(), this.month(), this.date());
+            break;
         case 'hour':
-            this.minutes(0);
-            /* falls through */
+            time = this._d.valueOf();
+            time -= mod(time + (this._isUTC ? 0 : this.utcOffset() * MS_PER_MINUTE), MS_PER_HOUR);
+            break;
         case 'minute':
-            this.seconds(0);
-            /* falls through */
+            time = this._d.valueOf();
+            time -= mod(time, MS_PER_MINUTE);
+            break;
         case 'second':
-            this.milliseconds(0);
-    }
-
-    // weeks are a special case
-    if (units === 'week') {
-        this.weekday(0);
-    }
-    if (units === 'isoWeek') {
-        this.isoWeekday(1);
-    }
-
-    // quarters are also special
-    if (units === 'quarter') {
-        this.month(Math.floor(this.month() / 3) * 3);
+            time = this._d.valueOf();
+            time -= mod(time, MS_PER_SECOND);
+            break;
     }
 
+    this._d.setTime(time);
+    hooks.updateOffset(this, true);
     return this;
 }
 
 export function endOf (units) {
+    var time;
     units = normalizeUnits(units);
-    if (units === undefined || units === 'millisecond') {
+    if (units === undefined || units === 'millisecond' || !this.isValid()) {
         return this;
     }
 
-    // 'date' is an alias for 'day', so it should be considered as such.
-    if (units === 'date') {
-        units = 'day';
+    var startOfDate = this._isUTC ? utcStartOfDate : localStartOfDate;
+
+    switch (units) {
+        case 'year':
+            time = startOfDate(this.year() + 1, 0, 1) - 1;
+            break;
+        case 'quarter':
+            time = startOfDate(this.year(), this.month() - this.month() % 3 + 3, 1) - 1;
+            break;
+        case 'month':
+            time = startOfDate(this.year(), this.month() + 1, 1) - 1;
+            break;
+        case 'week':
+            time = startOfDate(this.year(), this.month(), this.date() - this.weekday() + 7) - 1;
+            break;
+        case 'isoWeek':
+            time = startOfDate(this.year(), this.month(), this.date() - (this.isoWeekday() - 1) + 7) - 1;
+            break;
+        case 'day':
+        case 'date':
+            time = startOfDate(this.year(), this.month(), this.date() + 1) - 1;
+            break;
+        case 'hour':
+            time = this._d.valueOf();
+            time += MS_PER_HOUR - mod(time + (this._isUTC ? 0 : this.utcOffset() * MS_PER_MINUTE), MS_PER_HOUR) - 1;
+            break;
+        case 'minute':
+            time = this._d.valueOf();
+            time += MS_PER_MINUTE - mod(time, MS_PER_MINUTE) - 1;
+            break;
+        case 'second':
+            time = this._d.valueOf();
+            time += MS_PER_SECOND - mod(time, MS_PER_SECOND) - 1;
+            break;
     }
 
-    return this.startOf(units).add(1, (units === 'isoWeek' ? 'week' : units)).subtract(1, 'ms');
+    this._d.setTime(time);
+    hooks.updateOffset(this, true);
+    return this;
 }

diff --git a/src/test/moment/start_end_of.js b/src/test/moment/start_end_of.js
index 4b47620d63d727679dad4432c03d16f6dea62eba..e3db910474d8f276b10fb700d285e9c91e640bc6 100644 (file)
--- a/src/test/moment/start_end_of.js
+++ b/src/test/moment/start_end_of.js
@@ -393,3 +393,27 @@ test('endOf millisecond and no-arg', function (assert) {
     assert.equal(+m, +m.clone().endOf('millisecond'), 'endOf with millisecond argument should change time');
     assert.equal(+m, +m.clone().endOf('milliseconds'), 'endOf with milliseconds argument should change time');
 });
+
+test('startOf for year zero', function (assert) {
+    var m = moment('0000-02-29T12:34:56.789Z').parseZone();
+    assert.equal(m.clone().startOf('ms').toISOString(), '0000-02-29T12:34:56.789Z',  'startOf millisecond should preserve year');
+    assert.equal(m.clone().startOf('s').toISOString(), '0000-02-29T12:34:56.000Z', 'startOf second should preserve year');
+    assert.equal(m.clone().startOf('m').toISOString(), '0000-02-29T12:34:00.000Z', 'startOf minute should preserve year');
+    assert.equal(m.clone().startOf('h').toISOString(), '0000-02-29T12:00:00.000Z', 'startOf hour should preserve year');
+    assert.equal(m.clone().startOf('d').toISOString(), '0000-02-29T00:00:00.000Z', 'startOf day should preserve year');
+    assert.equal(m.clone().startOf('M').toISOString(), '0000-02-01T00:00:00.000Z', 'startOf month should preserve year');
+    assert.equal(m.clone().startOf('Q').toISOString(), '0000-01-01T00:00:00.000Z', 'startOf quarter should preserve year');
+    assert.equal(m.clone().startOf('y').toISOString(), '0000-01-01T00:00:00.000Z', 'startOf year should preserve year');
+});
+
+test('endOf for year zero', function (assert) {
+    var m = moment('0000-02-29T12:34:56.789Z').parseZone();
+    assert.equal(m.clone().endOf('ms').toISOString(), '0000-02-29T12:34:56.789Z',  'endOf millisecond should preserve year');
+    assert.equal(m.clone().endOf('s').toISOString(), '0000-02-29T12:34:56.999Z', 'endOf second should preserve year');
+    assert.equal(m.clone().endOf('m').toISOString(), '0000-02-29T12:34:59.999Z', 'endOf minute should preserve year');
+    assert.equal(m.clone().endOf('h').toISOString(), '0000-02-29T12:59:59.999Z', 'endOf hour should preserve year');
+    assert.equal(m.clone().endOf('d').toISOString(), '0000-02-29T23:59:59.999Z', 'endOf day should preserve year');
+    assert.equal(m.clone().endOf('M').toISOString(), '0000-02-29T23:59:59.999Z', 'endOf month should preserve year');
+    assert.equal(m.clone().endOf('Q').toISOString(), '0000-03-31T23:59:59.999Z', 'endOf quarter should preserve year');
+    assert.equal(m.clone().endOf('y').toISOString(), '0000-12-31T23:59:59.999Z', 'endOf year should preserve year');
+});