Updating Angular version

third_party/pkg/angular/lib/directive/ng_pluralize.dart

+part of angular.directive;
+
+/**
+ * ## Overview
+ * `ngPluralize` is a directive that displays messages according to locale rules.
+ *
+ * You configure ngPluralize directive by specifying the mappings between plural
+ * categories and the strings to be displayed.
+ *
+ * ## Plural categories and explicit number rules
+ * The available plural categories are:
+ * * "zero",
+ * * "one",
+ * * "two",
+ * * "few",
+ * * "many",
+ * * "other".
+ *
+ * While a plural category may match many numbers, an explicit number rule can only match
+ * one number. For example, the explicit number rule for "3" matches the number 3. There
+ * are examples of plural categories and explicit number rules throughout the rest of this
+ * documentation.
+ *
+ * ## Configuring ngPluralize
+ * You configure ngPluralize by providing 2 attributes: `count` and `when`.
+ * You can also provide an optional attribute, `offset`.
+ *
+ * The value of the `count` attribute can be either a string or an expression; these are
+ * evaluated on the current scope for its bound value.
+ *
+ * The `when` attribute specifies the mappings between plural categories and the actual
+ * string to be displayed. The value of the attribute should be a JSON object.
+ *
+ * The following example shows how to configure ngPluralize:
+ *
+ *    <ng-pluralize count="personCount"
+ *                  when="{'0': 'Nobody is viewing.',
+ *                         'one': '1 person is viewing.',
+ *                         'other': '{} people are viewing.'}">
+ *    </ng-pluralize>
+ *
+ * In the example, `"0: Nobody is viewing."` is an explicit number rule. If you did not
+ * specify this rule, 0 would be matched to the "other" category and "0 people are viewing"
+ * would be shown instead of "Nobody is viewing". You can specify an explicit number rule for
+ * other numbers, for example 12, so that instead of showing "12 people are viewing", you can
+ * show "a dozen people are viewing".
+ *
+ * You can use a set of closed braces (`{}`) as a placeholder for the number that you want substituted
+ * into pluralized strings. In the previous example, Angular will replace `{}` with
+ * `{{personCount}}`. The closed braces `{}` is a placeholder {{numberExpression}}.
+ *
+ * ## Configuring ngPluralize with offset
+ * The `offset` attribute allows further customization of pluralized text, which can result in
+ * a better user experience. For example, instead of the message "4 people are viewing this document",
+ * you might display "John, Kate and 2 others are viewing this document".
+ * The offset attribute allows you to offset a number by any desired value.
+ * Let's take a look at an example:
+ *
+ *    <ng-pluralize count="personCount" offset=2
+ *                  when="{'0': 'Nobody is viewing.',
+ *                         '1': '{{person1}} is viewing.',
+ *                         '2': '{{person1}} and {{person2}} are viewing.',
+ *                         'one': '{{person1}}, {{person2}} and one other person are viewing.',
+ *                         'other': '{{person1}}, {{person2}} and {} other people are viewing.'}">
+ *    </ng-pluralize>
+ *
+ * Notice that we are still using two plural categories(one, other), but we added
+ * three explicit number rules 0, 1 and 2.
+ * When one person, perhaps John, views the document, "John is viewing" will be shown.
+ * When three people view the document, no explicit number rule is found, so
+ * an offset of 2 is taken off 3, and Angular uses 1 to decide the plural category.
+ * In this case, plural category 'one' is matched and "John, Marry and one other person are viewing"
+ * is shown.
+ *
+ * Note that when you specify offsets, you must provide explicit number rules for
+ * numbers from 0 up to and including the offset. If you use an offset of 3, for example,
+ * you must provide explicit number rules for 0, 1, 2 and 3. You must also provide plural strings for
+ * at least the "other" plural category.
+ */
+ @NgDirective(
+    selector: 'ng-pluralize',
+    map: const { 'count': '=>count' })
+@NgDirective(
+    selector: '[ng-pluralize]',
+    map: const { 'count': '=>count' })
+class NgPluralizeDirective {
+
+  final dom.Element element;
+  final Scope scope;
+  final Interpolate interpolate;
+  int offset;
+  Map<String, String> discreteRules = new Map();
+  Map<Symbol, String> categoryRules = new Map();
+  static final RegExp IS_WHEN = new RegExp(r'^when-(minus-)?.');
+
+  NgPluralizeDirective(this.scope, this.element, this.interpolate, NodeAttrs attributes) {
+    Map<String, String> whens = attributes['when'] == null ? {} : scope.$eval(attributes['when']);
+    offset = attributes['offset'] == null ? 0 : int.parse(attributes['offset']);
+
+    element.attributes.keys.where((k) => IS_WHEN.hasMatch(k)).forEach((k) {
+      var ruleName = k.replaceFirst('when-', '').replaceFirst('minus-', '-');
+      whens[ruleName] = element.attributes[k];
+    });
+
+    if (whens['other'] == null) {
+      throw "ngPluralize error! The 'other' plural category must always be specified";
+    }
+
+    whens.forEach((k, v) {
+      if (['zero', 'one', 'two', 'few', 'many', 'other'].contains(k)) {
+        this.categoryRules[new Symbol(k.toString())] = v;
+      } else {
+        this.discreteRules[k.toString()] = v;
+      }
+    });
+  }
+
+  set count(value) {
+    if (value is! num) {
+      try {
+        value = int.parse(value);
+      } catch(e) {
+        try {
+          value = double.parse(value);
+        } catch(e) {
+          element.text = '';
+          return;
+        }
+      }
+    }
+
+    String stringValue = value.toString();
+    int intValue = value.toInt();
+
+    if (discreteRules[stringValue] != null) {
+      _setAndWatch(discreteRules[stringValue]);
+    } else {
+      intValue -= offset;
+      var exp = Function.apply(Intl.plural, [intValue], categoryRules);
+      if (exp != null) {
+        exp = exp.replaceAll(r'{}', (value - offset).toString());
+        _setAndWatch(exp);
+      }
+    }
+  }
+
+  _setAndWatch(expression) {
+    Interpolation interpolation = interpolate(expression);
+    interpolation.setter = (text) => element.text = text;
+    interpolation.setter(expression);
+    scope.$watchSet(interpolation.watchExpressions, interpolation.call);
+  }
+}