fixed #23

lib/abi.js

@@ -211,6 +211,7 @@ var signedIsNegative = function (value) {
 /// Formats input right-aligned input bytes to int
 /// @returns right-aligned input bytes formatted to int
 var formatOutputInt = function (value) {
+    value = value || "0";
     // check if it's negative number
     // it it is, return two's complement
     if (signedIsNegative(value)) {
@@ -222,6 +223,7 @@ var formatOutputInt = function (value) {
 /// Formats big right-aligned input bytes to uint
 /// @returns right-aligned input bytes formatted to uint
 var formatOutputUInt = function (value) {
+    value = value || "0";
     return new BigNumber(value, 16);
 };
 

lib/web3.js

@@ -233,7 +233,9 @@ var web3 = {
 
     /// @returns decimal representaton of hex value prefixed by 0x
     toDecimal: function (val) {
-        return (new BigNumber(val.substring(2), 16).toString(10));
+        // remove 0x and place 0, if it's required
+        val = val.length > 2 ? val.substring(2) : "0";
+        return (new BigNumber(val, 16).toString(10));
     },
 
     /// @returns hex representation (prefixed by 0x) of decimal value

test/abi.parsers.js

@@ -823,6 +823,38 @@ describe('abi', function() {
 
         });
 
+        it('should parse 0x value', function () {
+
+            // given
+            var d = clone(description);
+            d[0].outputs = [
+                { type: 'int' }
+            ];
+
+            // when
+            var parser = abi.outputParser(d);
+
+            // then
+            assert.equal(parser.test("0x")[0], 0);
+
+        });
+
+        it('should parse 0x value', function () {
+
+            // given
+            var d = clone(description);
+            d[0].outputs = [
+                { type: 'uint' }
+            ];
+
+            // when
+            var parser = abi.outputParser(d);
+
+            // then
+            assert.equal(parser.test("0x")[0], 0);
+
+        });
+
     });
 });