Support "D" for ordinal date in Intl.DateFormat

pkg/intl/lib/src/date_format_field.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of intl;
 
 /**
  * This is a private class internal to DateFormat which is used for formatting
  * particular fields in a template. e.g. if the format is hh:mm:ss then the
  * fields would be "hh", ":", "mm", ":", and "ss". Each type of field knows
@@ skipping 112 matching lines @@
   /**
    * Parse a field representing part of a date pattern. Note that we do not
    * return a value, but rather build up the result in [builder].
    */
   void parseField(_Stream input, _DateBuilder builder) {
    try {
      switch(pattern[0]) {
        case 'a': parseAmPm(input, builder); break;
        case 'c': parseStandaloneDay(input); break;
        case 'd': handleNumericField(input, builder.setDay); break; // day
+       // Day of year. Setting month=January with any day of the year works
+       case 'D': handleNumericField(input, builder.setDay); break; // dayofyear
        case 'E': parseDayOfWeek(input); break;
        case 'G': break; // era
        case 'h': parse1To12Hours(input, builder); break;
        case 'H': handleNumericField(input, builder.setHour); break; // hour 0-23
        case 'K': handleNumericField(input, builder.setHour); break; //hour 0-11
        case 'k': handleNumericField(input, builder.setHour,-1); break; //hr 1-24
        case 'L': parseStandaloneMonth(input, builder); break;
        case 'M': parseMonth(input, builder); break;
        case 'm': handleNumericField(input, builder.setMinute); break; // minutes
        case 'Q': break; // quarter
        case 'S': handleNumericField(input, builder.setFractionalSecond); break;
        case 's': handleNumericField(input, builder.setSecond); break;
        case 'v': break; // time zone id
        case 'y': handleNumericField(input, builder.setYear); break;
        case 'z': break; // time zone
        case 'Z': break; // time zone RFC
        default: return;
      }
    } catch (e) { throwFormatException(input); }
  }
 
   /** Formatting logic if we are of type FIELD */
   String formatField(DateTime date) {
      switch (pattern[0]) {
       case 'a': return formatAmPm(date);
       case 'c': return formatStandaloneDay(date);
       case 'd': return formatDayOfMonth(date);
+      case 'D': return formatDayOfYear(date);
       case 'E': return formatDayOfWeek(date);
       case 'G': return formatEra(date);
       case 'h': return format1To12Hours(date);
       case 'H': return format0To23Hours(date);
       case 'K': return format0To11Hours(date);
       case 'k': return format24Hours(date);
       case 'L': return formatStandaloneMonth(date);
       case 'M': return formatMonth(date);
       case 'm': return formatMinutes(date);
       case 'Q': return formatQuarter(date);
@@ skipping 179 matching lines @@
     if (width < 4) {
       return symbols.SHORTQUARTERS[quarter];
     } else {
       return symbols.QUARTERS[quarter];
     }
   }
   String formatDayOfMonth(DateTime date) {
     return padTo(width, date.day);
   }
 
+  String formatDayOfYear(DateTime date) => padTo(width, dayNumberInYear(date));
+
+  /** Return the ordinal day, i.e. the day number in the year. */
+  int dayNumberInYear(DateTime date) {
+    if (date.month == 1) return date.day;
+    if (date.month == 2) return date.day + 31;
+    return ordinalDayFromMarchFirst(date) + 59 + (isLeapYear(date) ? 1 : 0);
+  }
+
+  /**
+   * Return the day of the year counting March 1st as 1, after which the
+   * number of days per month is constant, so it's easier to calculate.
+   * Formula from http://en.wikipedia.org/wiki/Ordinal_date
+   */
+  int ordinalDayFromMarchFirst(DateTime date) =>
+      ((30.6 * date.month) - 91.4).floor() + date.day;
+
+  /**
+   * Return true if this is a leap year. Rely on [DateTime] to do the
+   * underlying calculation, even though it doesn't expose the test to us. */

[Emily Fortuna, 2013/09/23 19:48:27]

nit end the */ on its own line

[Alan Knight, 2013/09/25 17:17:58]

Done.

+  bool isLeapYear(DateTime date) {
+    var feb29 = new DateTime(date.year, 2, 29);
+    return feb29.month == 2;
+  }
+
   String formatDayOfWeek(DateTime date) {
     // Note that Dart's weekday returns 1 for Monday and 7 for Sunday.
     return (width >= 4 ? symbols.WEEKDAYS :
                         symbols.SHORTWEEKDAYS)[(date.weekday) % 7];
   }
 
   void parseDayOfWeek(_Stream input) {
     // This is IGNORED, but we still have to skip over it the correct amount.
     var possibilities = width >= 4 ? symbols.WEEKDAYS : symbols.SHORTWEEKDAYS;
     parseEnumeratedString(input, possibilities);
@@ skipping 28 matching lines @@
     var basicString = toBePrinted.toString();
     if (basicString.length >= width) return basicString;
     var buffer = new StringBuffer();
     for (var i = 0; i < width - basicString.length; i++) {
       buffer.write('0');
      }
     buffer.write(basicString);
     return buffer.toString();
   }
 }