allow *0* is valid template string value

Author: etpinard

src/lib/index.js

@@ -989,11 +989,14 @@ lib.templateString = function(string, obj) {
     var getterCache = {};
 
     return string.replace(lib.TEMPLATE_STRING_REGEX, function(dummy, key) {
+        var v;
         if(SIMPLE_PROPERTY_REGEX.test(key)) {
-            return obj[key] || '';
+            v = obj[key];
+        } else {
+            getterCache[key] = getterCache[key] || lib.nestedProperty(obj, key).get;
+            v = getterCache[key]();
         }
-        getterCache[key] = getterCache[key] || lib.nestedProperty(obj, key).get;
-        return getterCache[key]() || '';
+        return lib.isValidTextValue(v) ? v : '';
     });
 };
 

test/jasmine/tests/lib_test.js

@@ -2229,6 +2229,14 @@ describe('Test lib.js:', function() {
         it('replaces empty key with empty string', function() {
             expect(Lib.templateString('foo %{} %{}', {})).toEqual('foo  ');
         });
+
+        it('should work with the number *0*', function() {
+            expect(Lib.templateString('%{group}', {group: 0})).toEqual('0');
+        });
+
+        it('should work with the number *0* (nested case)', function() {
+            expect(Lib.templateString('%{x.y}', {'x': {y: 0}})).toEqual('0');
+        });
     });
 
     describe('hovertemplateString', function() {