Merge pull request #167 from Enlighten/master

Load an unloaded zone file linked from the backward file

spec/tz.default.spec.js

@@ -12,4 +12,11 @@ describe('TimezoneJS', function () {
     expect(sampleTz).toBeDefined();
     expect(sampleTz.tzAbbr).toEqual('ICT');
   });
+
+  it('should load an unloaded zone file linked from the backward file', function () {
+    sampleTz = timezoneJS.timezone.getTzInfo(new Date(), 'Antarctica/South_Pole');
+    expect(timezoneJS.timezone.loadedZones).toEqual({ asia: true, antarctica: true, backward: true, australasia: true });
+    expect(sampleTz.tzAbbr).toEqual('NZDT');
+  });
+
 });

src/date.js

@@ -654,6 +654,10 @@
           // legacy zone we need the backward file for.
           _this.loadZoneFile('backward');
           return getZone(dt, tz);
+        } else if (t && t !== tz) {
+          //Load the linked zone found in the backward file
+          _this.lazyLoadZoneFiles(t);
+          return getZone(dt, t);
         }
         invalidTZError(t);
       }
@@ -1049,16 +1053,7 @@
     //Expose transport mechanism and allow overwrite.
     this.transport = _transport;
     this.getTzInfo = function (dt, tz, isUTC) {
-      //Lazy-load any zones not yet loaded.
-      if (this.loadingScheme === this.loadingSchemes.LAZY_LOAD) {
-        //Get the correct region for the zone.
-        var zoneFile = getRegionForTimezone(tz);
-        if (!zoneFile) {
-          throw new Error('Not a valid timezone ID.');
-        }
-        //Get the file and parse it -- use synchronous XHR.
-        this.loadZoneFiles(zoneFile);
-      }
+      this.lazyLoadZoneFiles(tz);
       var z = getZone(dt, tz);
       var off = +z[0];
       //See if the offset needs adjustment.
@@ -1069,5 +1064,17 @@
       var abbr = getAbbreviation(z, rule);
       return { tzOffset: off, tzAbbr: abbr };
     };
+    //Lazy-load any zones not yet loaded.
+    this.lazyLoadZoneFiles = function(tz) {
+      if (this.loadingScheme === this.loadingSchemes.LAZY_LOAD) {
+        //Get the correct region for the zone.
+        var zoneFile = getRegionForTimezone(tz);
+        if (!zoneFile) {
+          throw new Error('Not a valid timezone ID.');
+        }
+        //Get the file and parse it -- use synchronous XHR.
+        this.loadZoneFiles(zoneFile);
+      }
+    };
   }();
 }).call(typeof window !== "undefined" ? window : this);