solidity methods "overloading"

dist/ethereum.js

@@ -331,15 +331,37 @@ var fromAbiOutput = function (json, methodName, output) {
     return result;
 };
 
+/// @returns display name for method eg. multiply(uint256) -> multiply
+var methodDisplayName = function (method) {
+    var length = method.indexOf('('); 
+    return length !== -1 ? method.substr(0, length) : method;
+};
+
+/// @returns overloaded part of method's name
+var methodTypeName = function (method) {
+    /// TODO: make it not vulnerable
+    var length = method.indexOf('(');
+    return length !== -1 ? method.substr(length + 1, method.length - 1 - (length + 1)) : "";
+};
+
 /// @param json abi for contract
 /// @returns input parser object for given json abi
 var inputParser = function (json) {
     var parser = {};
     json.forEach(function (method) {
-        parser[method.name] = function () {
+        var displayName = methodDisplayName(method.name); 
+        var typeName = methodTypeName(method.name);
+
+        var impl = function () {
             var params = Array.prototype.slice.call(arguments);
             return toAbiInput(json, method.name, params);
         };
+       
+        if (parser[displayName] === undefined) {
+            parser[displayName] = impl;
+        }
+
+        parser[displayName][typeName] = impl;
     });
 
     return parser;
@@ -350,9 +372,19 @@ var inputParser = function (json) {
 var outputParser = function (json) {
     var parser = {};
     json.forEach(function (method) {
-        parser[method.name] = function (output) {
+
+        var displayName = methodDisplayName(method.name); 
+        var typeName = methodTypeName(method.name);
+
+        var impl = function (output) {
             return fromAbiOutput(json, method.name, output);
         };
+
+        if (parser[displayName] === undefined) {
+            parser[displayName] = impl;
+        }
+
+        parser[displayName][typeName] = impl;
     });
 
     return parser;
@@ -362,21 +394,15 @@ var outputParser = function (json) {
 /// @param method name for which we want to get method signature
 /// @returns (promise) contract method signature for method with given name
 var methodSignature = function (json, name) {
-    var method = json[findMethodIndex(json, name)];
-    var result = name + '(';
-    var inputTypes = method.inputs.map(function (inp) {
-        return inp.type;
-    });
-    result += inputTypes.join(',');
-    result += ')';
-
-    return web3.sha3(web3.fromAscii(result));
+    return web3.sha3(web3.fromAscii(name));
 };
 
 module.exports = {
     inputParser: inputParser,
     outputParser: outputParser,
-    methodSignature: methodSignature
+    methodSignature: methodSignature,
+    methodDisplayName: methodDisplayName,
+    methodTypeName: methodTypeName
 };
 
 
@@ -552,12 +578,16 @@ var contract = function (address, desc) {
     var contract = {};
 
     desc.forEach(function (method) {
-        contract[method.name] = function () {
+
+        var displayName = abi.methodDisplayName(method.name);
+        var typeName = abi.methodTypeName(method.name);
+
+        var impl = function () {
             var params = Array.prototype.slice.call(arguments);
-            var parsed = inputParser[method.name].apply(null, params);
+            var parsed = inputParser[displayName][typeName].apply(null, params);
 
             var onSuccess = function (result) {
-                return outputParser[method.name](result);
+                return outputParser[displayName][typeName](result);
             };
 
             return {
@@ -579,6 +609,12 @@ var contract = function (address, desc) {
                 }
             };
         };
+
+        if (contract[displayName] === undefined) {
+            contract[displayName] = impl;
+        }
+
+        contract[displayName][typeName] = impl;
     });
 
     return contract;

example/contract.html

@@ -20,7 +20,7 @@
 
     // contract description, this will be autogenerated somehow
     var desc =  [{
-        "name": "multiply",
+        "name": "multiply(uint256)",
         "inputs": [
         {
             "name": "a",

lib/abi.js

@@ -330,15 +330,37 @@ var fromAbiOutput = function (json, methodName, output) {
     return result;
 };
 
+/// @returns display name for method eg. multiply(uint256) -> multiply
+var methodDisplayName = function (method) {
+    var length = method.indexOf('('); 
+    return length !== -1 ? method.substr(0, length) : method;
+};
+
+/// @returns overloaded part of method's name
+var methodTypeName = function (method) {
+    /// TODO: make it not vulnerable
+    var length = method.indexOf('(');
+    return length !== -1 ? method.substr(length + 1, method.length - 1 - (length + 1)) : "";
+};
+
 /// @param json abi for contract
 /// @returns input parser object for given json abi
 var inputParser = function (json) {
     var parser = {};
     json.forEach(function (method) {
-        parser[method.name] = function () {
+        var displayName = methodDisplayName(method.name); 
+        var typeName = methodTypeName(method.name);
+
+        var impl = function () {
             var params = Array.prototype.slice.call(arguments);
             return toAbiInput(json, method.name, params);
         };
+       
+        if (parser[displayName] === undefined) {
+            parser[displayName] = impl;
+        }
+
+        parser[displayName][typeName] = impl;
     });
 
     return parser;
@@ -349,9 +371,19 @@ var inputParser = function (json) {
 var outputParser = function (json) {
     var parser = {};
     json.forEach(function (method) {
-        parser[method.name] = function (output) {
+
+        var displayName = methodDisplayName(method.name); 
+        var typeName = methodTypeName(method.name);
+
+        var impl = function (output) {
             return fromAbiOutput(json, method.name, output);
         };
+
+        if (parser[displayName] === undefined) {
+            parser[displayName] = impl;
+        }
+
+        parser[displayName][typeName] = impl;
     });
 
     return parser;
@@ -361,20 +393,14 @@ var outputParser = function (json) {
 /// @param method name for which we want to get method signature
 /// @returns (promise) contract method signature for method with given name
 var methodSignature = function (json, name) {
-    var method = json[findMethodIndex(json, name)];
-    var result = name + '(';
-    var inputTypes = method.inputs.map(function (inp) {
-        return inp.type;
-    });
-    result += inputTypes.join(',');
-    result += ')';
-
-    return web3.sha3(web3.fromAscii(result));
+    return web3.sha3(web3.fromAscii(name));
 };
 
 module.exports = {
     inputParser: inputParser,
     outputParser: outputParser,
-    methodSignature: methodSignature
+    methodSignature: methodSignature,
+    methodDisplayName: methodDisplayName,
+    methodTypeName: methodTypeName
 };
 

lib/contract.js

@@ -53,12 +53,16 @@ var contract = function (address, desc) {
     var contract = {};
 
     desc.forEach(function (method) {
-        contract[method.name] = function () {
+
+        var displayName = abi.methodDisplayName(method.name);
+        var typeName = abi.methodTypeName(method.name);
+
+        var impl = function () {
             var params = Array.prototype.slice.call(arguments);
-            var parsed = inputParser[method.name].apply(null, params);
+            var parsed = inputParser[displayName][typeName].apply(null, params);
 
             var onSuccess = function (result) {
-                return outputParser[method.name](result);
+                return outputParser[displayName][typeName](result);
             };
 
             return {
@@ -80,6 +84,12 @@ var contract = function (address, desc) {
                 }
             };
         };
+
+        if (contract[displayName] === undefined) {
+            contract[displayName] = impl;
+        }
+
+        contract[displayName][typeName] = impl;
     });
 
     return contract;

test/abi.parsers.js

@@ -48,7 +48,6 @@ describe('abi', function() {
             assert.equal(parser.test('0.1'), "0000000000000000000000000000000000000000000000000000000000000000");
             assert.equal(parser.test('3.9'), "0000000000000000000000000000000000000000000000000000000000000003");
 
-
         });
 
         it('should parse input uint128', function() {
@@ -321,7 +320,7 @@ describe('abi', function() {
         
             // given
             var d = clone(description);
-            d[0].name = 'helloworld';
+            d[0].name = 'helloworld(int)';
             d[0].inputs = [
                 { type: "int" }
             ];
@@ -331,6 +330,7 @@ describe('abi', function() {
 
             // then
             assert.equal(parser.helloworld(1), "0000000000000000000000000000000000000000000000000000000000000001");
+            assert.equal(parser.helloworld['int'](1), "0000000000000000000000000000000000000000000000000000000000000001");
 
         });
         
@@ -755,7 +755,7 @@ describe('abi', function() {
         
             // given
             var d = clone(description);
-            d[0].name = 'helloworld';
+            d[0].name = 'helloworld(int)';
             d[0].outputs = [
                 { type: "int" }
             ];
@@ -765,6 +765,7 @@ describe('abi', function() {
 
             // then
             assert.equal(parser.helloworld("0x0000000000000000000000000000000000000000000000000000000000000001")[0], 1);
+            assert.equal(parser.helloworld['int']("0x0000000000000000000000000000000000000000000000000000000000000001")[0], 1);
 
         });