Fix makeAs to work with zoned moments

Clone the model to get all plugin data (like zones), than move the time so that
it matches the input and recompute the timezone.

Closes #1952, #1956, #1772

diff --git a/moment.js b/moment.js
index 1cc739bd4743eb44a8e439df8292420e3b23eff3..40ab6880bdd02b53ec9aad8e7e9aa6d4938bc88b 100644 (file)
--- a/moment.js
+++ b/moment.js
@@ -776,8 +776,18 @@
 
     // Return a moment from input, that is local/utc/zone equivalent to model.
     function makeAs(input, model) {
-        return model._isUTC ? moment(input).zone(model._offset || 0) :
-            moment(input).local();
+        var res, diff;
+        if (model._isUTC) {
+            res = model.clone();
+            diff = (moment.isMoment(input) || isDate(input) ?
+                    +input : +moment(input)) - (+res);
+            // Use low-level api, because this fn is low-level api.
+            res._d.setTime(+res._d + diff);
+            moment.updateOffset(res, false);
+            return res;
+        } else {
+            return moment(input).local();
+        }
     }
 
     /************************************