Add UtcPipe to enable UTC mode in pipe chain.

.gitignore

@@ -31,6 +31,9 @@ add.pipe.d.ts
 subtract.pipe.js
 subtract.pipe.js.map
 subtract.pipe.d.ts
+utc.pipe.js
+utc.pipe.js.map
+utc.pipe.d.ts
 *.spec.js
 *.spec.js.map
 *.spec.d.ts

README.md

@@ -190,6 +190,21 @@ Use these pipes to perform date arithmetics. See [Momnet.js documentation](http:
 
 *Example for amAdd/amSubtract is needed here, Pull Requests are welcome*
 
+## amUtc pipe
+
+Enables UTC mode for subsequent moment operations (such as displaying the time in UTC).
+
+``` typescript
+@Component({
+  selector: 'app',
+  template: `
+    Last updated: {{ '2016-12-31T23:00:00.000-01:00' | amUtc | amDateFormat: 'YYYY-MM-DD' }}
+  `
+})
+```
+
+Prints `Last updated: 2017-01-01`
+
 Complete Example
 ----------------
 

package.json

@@ -45,6 +45,10 @@
     "subtract.pipe.js.map",
     "subtract.pipe.d.ts",
     "subtract.pipe.metadata.json",
+    "utc.pipe.js",
+    "utc.pipe.js.map",
+    "utc.pipe.d.ts",
+    "utc.pipe.metadata.json",
     "CHANGELOG.md"
   ],
   "scripts": {

src/index.ts

@@ -5,3 +5,4 @@ export { DurationPipe } from './duration.pipe';
 export { FromUnixPipe } from './from-unix.pipe';
 export { MomentModule } from './moment.module';
 export { TimeAgoPipe } from './time-ago.pipe';
+export { UtcPipe } from './utc.pipe';

src/moment.module.ts

@@ -6,8 +6,10 @@ import { DifferencePipe } from './difference.pipe';
 import { DurationPipe } from './duration.pipe';
 import { FromUnixPipe } from './from-unix.pipe';
 import { TimeAgoPipe } from './time-ago.pipe';
+import { UtcPipe } from './utc.pipe';
 
-const ANGULAR_MOMENT_PIPES = [CalendarPipe, DateFormatPipe, DifferencePipe, DurationPipe, FromUnixPipe, TimeAgoPipe];
+const ANGULAR_MOMENT_PIPES = [CalendarPipe, DateFormatPipe, DifferencePipe, DurationPipe, FromUnixPipe, TimeAgoPipe,
+   UtcPipe];
 
 @NgModule({
   declarations: ANGULAR_MOMENT_PIPES,

src/utc.pipe.spec.ts

@@ -0,0 +1,61 @@
+import 'es6-shim';
+import 'reflect-metadata';
+import * as moment from 'moment';
+import { DateFormatPipe } from './date-format.pipe';
+import { UtcPipe } from './utc.pipe';
+
+describe('UtcPipe', () => {
+
+  describe('#transform', () => {
+
+    let utcDatePipe: UtcPipe;
+
+    beforeEach(() => {
+      utcDatePipe = new UtcPipe();
+    });
+
+    it('should output an invalid momemt object for a null input', () => {
+      const utcDate = utcDatePipe.transform(null);
+      expect(utcDate).toEqual(jasmine.any(moment));
+      expect(utcDate.isValid()).toBe(false);
+    });
+
+    it('should output a moment object for a moment input', () => {
+      const momentDate = moment();
+      const utcDate = utcDatePipe.transform(momentDate);
+      expect(utcDate).toEqual(jasmine.any(moment));
+      expect(utcDate.isValid()).toBe(true);
+    });
+
+    it('should output a moment object for a date input', () => {
+      const date = new Date();
+      const utcDate = utcDatePipe.transform(date);
+      expect(utcDate).toEqual(jasmine.any(moment));
+      expect(utcDate.isValid()).toBe(true);
+    });
+
+    it('should output a moment object for a string date', () => {
+      const dateString = '2016-01-01';
+      const utcDate = utcDatePipe.transform(dateString);
+      expect(utcDate).toEqual(jasmine.any(moment));
+      expect(utcDate.isValid()).toBe(true);
+    });
+
+    it('should output a moment object for a timestamp', () => {
+      const timestamp: number = Date.now();
+      const utcDate = utcDatePipe.transform(timestamp);
+      expect(utcDate).toEqual(jasmine.any(moment));
+      expect(utcDate.isValid()).toBe(true);
+    });
+
+    it('should be pipeable to amDateFormat', () => {
+      const amDateFormat = new DateFormatPipe();
+      const datetimeString = '2015-12-31T23:00:00.000-01:00';
+      const momentFormatString = 'YYYY-MM-DD';
+      const utcOutput = utcDatePipe.transform(datetimeString);
+      expect(amDateFormat.transform(utcOutput, momentFormatString)).toEqual('2016-01-01');
+    });
+
+  });
+
+});

src/utc.pipe.ts

@@ -0,0 +1,12 @@
+import { Pipe, PipeTransform } from '@angular/core';
+import * as moment from 'moment';
+
+// under systemjs, moment is actually exported as the default export, so we account for that
+const momentConstructor: (value?: any) => moment.Moment = (<any>moment).default || moment;
+
+@Pipe({ name: 'amUtc' })
+export class UtcPipe implements PipeTransform {
+  transform(value: Date | moment.Moment | string | number): moment.Moment {
+    return moment(value).utc();
+  }
+}

tsconfig.json

@@ -27,6 +27,8 @@
     "src/duration.pipe.spec.ts",
     "src/time-ago.pipe.ts",
     "src/time-ago.pipe.spec.ts",
+    "src/utc.pipe.ts",
+    "src/utc.pipe.spec.ts",
     "src/moment.module.ts",
     "src/index.ts"
   ],