fix(ngPluralize): cap value - offset to 0

BREAKING CHANGE:

ngPluralize won't produce messages with signed (negative) values anymore.

Author: caitp

src/ng/directive/ngPluralize.js

@@ -172,6 +172,15 @@
           person2.sendKeys('Vojta');
           expect(withOffset.getText()).toEqual('Di, Vojta and 2 other people are viewing.');
         });
+        it('should reset count to 0 if count - offset is negative', function() {
+          var withOffset = element.all(by.css('ng-pluralize')).get(1);
+          var personCount = element(by.model('personCount'));
+          personCount.clear();
+          personCount.sendKeys('4');
+          expect(withOffset.getText()).toEqual('Igor, Misko and 2 other people are viewing.');
+          personCount.clear();
+          expect(withOffset.getText()).toEqual('Nobody is viewing.');
+        });
       </file>
     </example>
  */
@@ -189,10 +198,19 @@ var ngPluralizeDirective = ['$locale', '$interpolate', '$log', function($locale,
           whensExpFns = {},
           startSymbol = $interpolate.startSymbol(),
           endSymbol = $interpolate.endSymbol(),
-          braceReplacement = startSymbol + numberExp + '-' + offset + endSymbol,
           watchRemover = angular.noop,
           lastCount;
 
+      var oneTimeCount = /^\s*::/.test(numberExp) || '';
+      if (oneTimeCount) {
+        numberExp = numberExp.replace(/^\s*::/, '');
+        oneTimeCount = '::';
+      }
+      var braceReplacement = [
+        startSymbol, oneTimeCount, '((', numberExp, '-', offset,
+        ') < 0 ?', 0, ':', numberExp, '-', offset, ')', endSymbol
+      ].join('');
+
       forEach(attr, function(expression, attributeName) {
         var tmpMatch = IS_WHEN.exec(attributeName);
         if (tmpMatch) {
@@ -205,7 +223,7 @@ var ngPluralizeDirective = ['$locale', '$interpolate', '$log', function($locale,
 
       });
 
-      scope.$watch(numberExp, function ngPluralizeWatchAction(newVal) {
+      scope.$watch(oneTimeCount + numberExp, function ngPluralizeWatchAction(newVal) {
         var count = parseFloat(newVal);
         var countIsNaN = isNaN(count);
 

test/ng/directive/ngPluralizeSpec.js

@@ -63,18 +63,18 @@ describe('ngPluralize', function() {
 
       $rootScope.email = -0.1;
       $rootScope.$digest();
-      expect(element.text()).toBe('You have -0.1 new emails');
-      expect(elementAlt.text()).toBe('You have -0.1 new emails');
+      expect(element.text()).toBe('You have 0 new emails');
+      expect(elementAlt.text()).toBe('You have 0 new emails');
 
       $rootScope.email = '-0.01';
       $rootScope.$digest();
-      expect(element.text()).toBe('You have -0.01 new emails');
-      expect(elementAlt.text()).toBe('You have -0.01 new emails');
+      expect(element.text()).toBe('You have 0 new emails');
+      expect(elementAlt.text()).toBe('You have 0 new emails');
 
       $rootScope.email = -2;
       $rootScope.$digest();
-      expect(element.text()).toBe('You have -2 new emails');
-      expect(elementAlt.text()).toBe('You have -2 new emails');
+      expect(element.text()).toBe('You have 0 new emails');
+      expect(elementAlt.text()).toBe('You have 0 new emails');
 
       $rootScope.email = -1;
       $rootScope.$digest();
@@ -111,8 +111,8 @@ describe('ngPluralize', function() {
 
       $rootScope.email = '-011';
       $rootScope.$digest();
-      expect(element.text()).toBe('You have -11 new emails');
-      expect(elementAlt.text()).toBe('You have -11 new emails');
+      expect(element.text()).toBe('You have 0 new emails');
+      expect(elementAlt.text()).toBe('You have 0 new emails');
 
       $rootScope.email = '1fff';
       $rootScope.$digest();