added contract.clone()

docs/web3-eth-contract.rst

@@ -197,6 +197,44 @@ Example
 
 ------------------------------------------------------------------------------
 
+clone
+=====================
+
+.. code-block:: javascript
+
+    myContract.clone()
+
+Clones the current contract instance.
+
+----------
+Parameters
+----------
+
+none
+
+-------
+Returns
+-------
+
+
+``Object``: The new contract instance.
+
+-------
+Example
+-------
+
+.. code-block:: javascript
+
+    var contract1 = new eth.Contract(abi, address, {gasPrice: '12345678', from: fromAddress});
+
+    var contract2 = contract1.clone();
+    contract2.options.address = address2;
+
+    (contract1.options.address !== contract2.options.address);
+    > true
+
+------------------------------------------------------------------------------
+
 
 .. _contract-deploy:
 

packages/web3-eth-contract/src/index.js

@@ -51,27 +51,27 @@ var Contract = function(jsonInterface, address, options) {
     var _this = this,
         args = Array.prototype.slice.call(arguments);
 
-    if(!(this instanceof Contract))
+    if(!(this instanceof Contract)) {
         throw new Error('Please use the "new" keyword to instantiate a web3.eth.contract() object!');
+    }
 
-    if(!jsonInterface || !(jsonInterface instanceof Array))
+    if(!jsonInterface || !(jsonInterface instanceof Array)) {
         throw new Error('You must provide the json interface of the contract when instatiating a contract object.');
+    }
 
-    // get the options object
+
+    // create the options object
     this.options = {};
+
     if(utils.isObject(args[args.length - 1])) {
         options = args[args.length - 1];
-        this.options.data = options.data;
-        this.options.from = options.from;
-        this.options.gasPrice = options.gasPrice;
-        this.options.gas = options.gas || options.gasLimit;
 
+        this.options = _.extend(this.options, this._fillWithDefaultOptions(options));
         if(utils.isObject(address)) {
             address = null;
         }
     }
 
-
     // set address
     Object.defineProperty(this.options, 'address', {
         set: function(value){
@@ -203,15 +203,17 @@ Contract.prototype._checkListener = function(type, event){
  * @return {Object} the options with gaps filled by defaults
  */
 Contract.prototype._fillWithDefaultOptions = function fillWithDefaultOptions(options) {
+    var gasPrice = options.gasPrice ? String(options.gasPrice): null;
 
     options.data = options.data || this.options.data;
-    options.from = options.from || this.options.from;
 
     if(utils.isAddress(options.from))
         options.from = options.from.toLowerCase();
 
-    options.gasPrice = options.gasPrice || this.options.gasPrice;
+    options.from = options.from || this.options.from;
+    options.gasPrice = gasPrice || this.options.gasPrice;
     options.gas = options.gas || options.gasLimit || this.options.gas;
+
     // TODO replace with only gasLimit?
     delete options.gasLimit;
 
@@ -508,7 +510,18 @@ Contract.prototype._generateEventOptions = function() {
 /**
  * Adds event listeners and creates a subscription, and remove it once its fired.
  *
- * @method on
+ * @method clone
+ * @return {Object} the event subscription
+ */
+Contract.prototype.clone = function() {
+    return new Contract(this.options.jsonInterface, this.options.address, this.options);
+};
+
+
+/**
+ * Adds event listeners and creates a subscription, and remove it once its fired.
+ *
+ * @method once
  * @param {String} event
  * @param {Object} options
  * @param {Function} callback
@@ -540,7 +553,7 @@ Contract.prototype.once = function(event, options, callback) {
 /**
  * Adds event listeners and creates a subscription.
  *
- * @method on
+ * @method _on
  * @param {String} event
  * @param {Object} options
  * @param {Function} callback

test/contract.js

@@ -113,6 +113,44 @@ describe('contract', function () {
 
             assert.throws(test);
         });
+        it('.clone() should properly clone the contract instance', function () {
+            var provider = new FakeHttpProvider();
+            var eth = new Eth(provider);
+            var fromAddress = '0xDDfFD0A3C12e86b4b5f39B213f7e19d048276daE';
+            var abi2 = [{
+                "name": "ballerRo",
+                "type": "function",
+                "inputs": [{
+                    "name": "So",
+                    "type": "address"
+                }],
+                "constant": true,
+                "outputs": [{
+                    "name": "man",
+                    "type": "uint256"
+                }]
+            }];
+
+            var contract1 = new eth.Contract(abi, address, {gas: 1222, gasPrice: 12345678, from: fromAddress});
+            var contract2 = contract1.clone();
+
+            assert.equal(contract1.options.address, address);
+            assert.equal(contract1.options.gas, 1222);
+            assert.equal(contract1.options.gasPrice, '12345678');
+            assert.deepEqual(contract1.options.jsonInterface, abi);
+
+
+            contract2.options.jsonInterface = abi2;
+            contract2.options.address = fromAddress;
+            contract2.options.gas = 300;
+            contract2.options.gasPrice = '234234';
+
+            assert.isFunction(contract2.methods.ballerRo);
+            assert.equal(contract2.options.address, fromAddress);
+            assert.equal(contract2.options.gas, 300);
+            assert.equal(contract2.options.gasPrice, '234234');
+            assert.deepEqual(contract2.options.jsonInterface, abi2);
+        });
     });
     describe('internal method', function () {
         it('_encodeEventABI should return the encoded event object without topics', function () {