feat(pipes): add date pipe

Closes #2877

modules/angular2/src/facade/intl.dart

@@ -40,3 +40,21 @@ class NumberFormatter {
     return formatter.format(number);
   }
 }
+
+class DateFormatter {
+  static RegExp _multiPartRegExp = new RegExp(r'^([yMdE]+)([Hjms]+)$');
+
+  static String format(DateTime date, String locale, String pattern) {
+    locale = _normalizeLocale(locale);
+    var formatter = new DateFormat(null, locale);
+    var matches = _multiPartRegExp.firstMatch(pattern);
+    if (matches != null) {
+      // Support for patterns which have known date and time components.
+      formatter.addPattern(matches[1]);
+      formatter.addPattern(matches[2], ', ');
+    } else {
+      formatter.addPattern(pattern);
+    }
+    return formatter.format(date);
+  }
+}

modules/angular2/src/facade/intl.ts

@@ -14,9 +14,7 @@ declare module Intl {
     format(value: number): string;
   }
 
-  var NumberFormat: {
-    new (locale?: string, options?: NumberFormatOptions): NumberFormat;
-  }
+  var NumberFormat: { new (locale?: string, options?: NumberFormatOptions): NumberFormat; }
 
   interface DateTimeFormatOptions {
     localeMatcher?: string;
@@ -37,9 +35,7 @@ declare module Intl {
     format(date?: Date | number): string;
   }
 
-  var DateTimeFormat: {
-    new (locale?: string, options?: DateTimeFormatOptions): DateTimeFormat;
-  }
+  var DateTimeFormat: { new (locale?: string, options?: DateTimeFormatOptions): DateTimeFormat; }
 }
 
 export enum NumberFormatStyle {
@@ -71,3 +67,78 @@ export class NumberFormatter {
     return new Intl.NumberFormat(locale, intlOptions).format(number);
   }
 }
+
+function digitCondition(len: int): string {
+  return len == 2 ? '2-digit' : 'numeric';
+}
+function nameCondition(len: int): string {
+  return len < 4 ? 'short' : 'long';
+}
+function extractComponents(pattern: string): Intl.DateTimeFormatOptions {
+  var ret: Intl.DateTimeFormatOptions = {};
+  var i = 0, j;
+  while (i < pattern.length) {
+    j = i;
+    while (j < pattern.length && pattern[j] == pattern[i]) j++;
+    let len = j - i;
+    switch (pattern[i]) {
+      case 'G':
+        ret.era = nameCondition(len);
+        break;
+      case 'y':
+        ret.year = digitCondition(len);
+        break;
+      case 'M':
+        if (len >= 3)
+          ret.month = nameCondition(len);
+        else
+          ret.month = digitCondition(len);
+        break;
+      case 'd':
+        ret.day = digitCondition(len);
+        break;
+      case 'E':
+        ret.weekday = nameCondition(len);
+        break;
+      case 'j':
+        ret.hour = digitCondition(len);
+        break;
+      case 'h':
+        ret.hour = digitCondition(len);
+        ret.hour12 = true;
+        break;
+      case 'H':
+        ret.hour = digitCondition(len);
+        ret.hour12 = false;
+        break;
+      case 'm':
+        ret.minute = digitCondition(len);
+        break;
+      case 's':
+        ret.second = digitCondition(len);
+        break;
+      case 'z':
+        ret.timeZoneName = 'long';
+        break;
+      case 'Z':
+        ret.timeZoneName = 'short';
+        break;
+    }
+    i = j;
+  }
+  return ret;
+}
+
+var dateFormatterCache: Map<string, Intl.DateTimeFormat> = new Map<string, Intl.DateTimeFormat>();
+
+export class DateFormatter {
+  static format(date: Date, locale: string, pattern: string): string {
+    var key = locale + pattern;
+    if (dateFormatterCache.has(key)) {
+      return dateFormatterCache.get(key).format(date);
+    }
+    var formatter = new Intl.DateTimeFormat(locale, extractComponents(pattern));
+    dateFormatterCache.set(key, formatter);
+    return formatter.format(date);
+  }
+}

modules/angular2/src/facade/lang.dart

@@ -33,6 +33,7 @@ bool isStringMap(obj) => obj is Map;
 bool isArray(obj) => obj is List;
 bool isPromise(obj) => obj is Future;
 bool isNumber(obj) => obj is num;
+bool isDate(obj) => obj is DateTime;
 
 String stringify(obj) => obj.toString();
 
@@ -232,8 +233,12 @@ class Json {
 }
 
 class DateWrapper {
+  static DateTime create(int year, [int month = 1, int day = 1, int hour = 0,
+      int minutes = 0, int seconds = 0, int milliseconds = 0]) {
+    return new DateTime(year, month, day, hour, minutes, seconds, milliseconds);
+  }
   static DateTime fromMillis(int ms) {
-    return new DateTime.fromMillisecondsSinceEpoch(ms);
+    return new DateTime.fromMillisecondsSinceEpoch(ms, isUtc: true);
   }
   static int toMillis(DateTime date) {
     return date.millisecondsSinceEpoch;
@@ -241,7 +246,7 @@ class DateWrapper {
   static DateTime now() {
     return new DateTime.now();
   }
-  static toJson(DateTime date) {
+  static String toJson(DateTime date) {
     return date.toUtc().toIso8601String();
   }
 }

modules/angular2/src/facade/lang.ts

@@ -93,6 +93,10 @@ export function isNumber(obj): boolean {
   return typeof obj === 'number';
 }
 
+export function isDate(obj): boolean {
+  return obj instanceof Date && !isNaN(obj.valueOf());
+}
+
 export function stringify(token): string {
   if (typeof token === 'string') {
     return token;
@@ -282,8 +286,12 @@ export class Json {
 }
 
 export class DateWrapper {
-  static fromMillis(ms): Date { return new Date(ms); }
-  static toMillis(date: Date): number { return date.getTime(); }
+  static create(year: int, month: int = 1, day: int = 1, hour: int = 0, minutes: int = 0,
+                seconds: int = 0, milliseconds: int = 0): Date {
+    return new Date(year, month - 1, day, hour, minutes, seconds, milliseconds);
+  }
+  static fromMillis(ms: int): Date { return new Date(ms); }
+  static toMillis(date: Date): int { return date.getTime(); }
   static now(): Date { return new Date(); }
-  static toJson(date): string { return date.toJSON(); }
+  static toJson(date: Date): string { return date.toJSON(); }
 }