fix(input): keep track of min/max attars on-the-fly

Now input[type=button] keeps track of both min and max attrs even if they change over time.

src/ng/directive/input.js

@@ -544,8 +544,8 @@ function numberInputType(scope, element, attr, ctrl, $sniffer, $browser) {
   });
 
   if (attr.min) {
-    var min = parseFloat(attr.min);
     var minValidator = function(value) {
+      var min = parseFloat(attr.min);
       if (!ctrl.$isEmpty(value) && value < min) {
         ctrl.$setValidity('min', false);
         return undefined;
@@ -560,8 +560,8 @@ function numberInputType(scope, element, attr, ctrl, $sniffer, $browser) {
   }
 
   if (attr.max) {
-    var max = parseFloat(attr.max);
     var maxValidator = function(value) {
+      var max = parseFloat(attr.max);
       if (!ctrl.$isEmpty(value) && value > max) {
         ctrl.$setValidity('max', false);
         return undefined;

test/ng/directive/inputSpec.js

@@ -667,6 +667,21 @@ describe('input', function() {
         expect(scope.value).toBe(100);
         expect(scope.form.alias.$error.min).toBeFalsy();
       });
+
+      it('should validate even if min value changes on-the-fly', function(done) {
+        scope.min = 10;
+        compileInput('<input type="number" ng-model="value" name="alias" min="{{min}}" />');
+        scope.$digest();
+
+        changeInputValueTo('5');
+        expect(inputElm).toBeInvalid();
+
+        scope.min = 0;
+        scope.$digest(function () {
+          expect(inputElm).toBeValid();
+          done();
+        });
+      });
     });
 
 
@@ -686,6 +701,21 @@ describe('input', function() {
         expect(scope.value).toBe(0);
         expect(scope.form.alias.$error.max).toBeFalsy();
       });
+
+      it('should validate even if max value changes on-the-fly', function(done) {
+        scope.max = 10;
+        compileInput('<input type="number" ng-model="value" name="alias" max="{{max}}" />');
+        scope.$digest();
+
+        changeInputValueTo('5');
+        expect(inputElm).toBeValid();
+
+        scope.max = 0;
+        scope.$digest(function () {
+          expect(inputElm).toBeInvalid();
+          done();
+        });
+      });
     });