merge develop

diff --cc moment.js
index 107fbc06108d96595d1b15ab0a39db1f5a1584a2,4a4e7fa367354c17f7f698a20029954c0d2021ef..322f43bd7be78d19af83ee12ddf70c422e113c31
--- 1/moment.js
--- 2/moment.js
+++ b/moment.js
@@@ -1431,14 -1390,9 +1431,15 @@@
          return normalizeUnits(units);
      };
  
 -    moment.invalid = function () {
 +    moment.invalid = function (flags) {
          var m = moment.utc(NaN);
 -        m._isValid = false;
 +        if (flags != null) {
 +            extend(m._pf, flags);
 +        }
 +        else {
 +            m._pf.userInvalidated = true;
 +        }
++
          return m;
      };
  

diff --cc test/moment/create.js
index 03adba3424275cc5ff3968589b32414e376a0971,bdf509f4069be64e1b5825e72a07164c56fc526e..3051136781a113424d03b66d53677b0bb9c3e813
--- 1/test/moment/create.js
--- 2/test/moment/create.js
+++ b/test/moment/create.js
@@@ -465,16 -449,14 +465,16 @@@ exports.create = 
          test.done();
      },
  
--    "null" : function (test) {
--        test.expect(6);
- 
-         test.ok(!moment('').isValid());
-         test.ok(!moment(null).isValid());
-         test.ok(!moment('', 'YYYY-MM-DD').isValid());
- 
-         test.ok(!moment.utc('').isValid(), "Calling moment.utc('')");
-         test.ok(!moment.utc(null).isValid(), "Calling moment.utc(null)");
-         test.ok(!moment.utc('', 'YYYY-MM-DD').isValid(), "Calling moment.utc('', 'YYYY-MM-DD')");
++    "null or empty" : function (test) {
++        test.expect(8);
+         test.equal(moment('').isValid(), false, "moment('') is not valid");
+         test.equal(moment(null).isValid(), false, "moment(null) is not valid");
++        test.equal(moment(null, 'YYYY-MM-DD').isValid(), false, "moment('', 'format') is not valid");
+         test.equal(moment('', 'YYYY-MM-DD').isValid(), false, "moment('', 'format') is not valid");
+         test.equal(moment.utc('').isValid(), false, "moment.utc('') is not valid");
+         test.equal(moment.utc(null).isValid(), false, "moment.utc(null) is not valid");
++        test.equal(moment.utc(null, 'YYYY-MM-DD').isValid(), false, "moment.utc(null) is not valid");
+         test.equal(moment.utc('', 'YYYY-MM-DD').isValid(), false, "moment.utc('', 'YYYY-MM-DD') is not valid");
          test.done();
      },
  

diff --cc test/moment/is_valid.js
index 99fc2c134f10860fc8f6ee4800ef299f256f24d3,fc47860dbf25e54c35e1ee139793b1540c947706..a4c8e74d65e9399141bb1be9e54c55b652b5cb33
--- 1/test/moment/is_valid.js
--- 2/test/moment/is_valid.js
+++ b/test/moment/is_valid.js
@@@ -227,26 -221,5 +227,26 @@@ exports.is_valid = 
  
          test.equal(moment(" ", "X").isValid(), false, 'string space');
          test.done();
 -    }
 +    },
 +
 +    "empty" : function (test) {
 +        test.equal(moment(null).isValid(), false, 'null');
 +        test.equal(moment('').isValid(), false, 'empty string');
 +        test.equal(moment(' ').isValid(), false, 'empty when trimmed');
 +
 +        test.equal(moment(null, 'YYYY').isValid(), false, 'format + null');
 +        test.equal(moment('', 'YYYY').isValid(), false, 'format + empty string');
 +        test.equal(moment(' ', 'YYYY').isValid(), false, 'format + empty when trimmed');
 +        test.done();
 +    },
 +
 +    "oddball permissiveness" : function (test) {
 +        //https://github.com/moment/moment/issues/1128
 +        test.ok(moment("2010-10-3199", ["MM/DD/YYYY", "MM-DD-YYYY", "YYYY-MM-DD"]).isValid());
 +
 +        //https://github.com/moment/moment/issues/1122
 +        test.ok(moment("3:25", ["h:mma", "hh:mma", "H:mm", "HH:mm"]).isValid());
 +
-         test.done()
++        test.done();
 +    },
  };