Merge branch 'develop'

1 files changed, 113 insertions, 0 deletions

diff --git a/lib/utils.js b/lib/utils.js
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+++ b/lib/utils.js
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+/*
+    This file is part of ethereum.js.
+
+    ethereum.js is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    ethereum.js is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with ethereum.js.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/** @file utils.js
+ * @authors:
+ *   Marek Kotewicz <marek@ethdev.com>
+ * @date 2015
+ */
+
+/// Finds first index of array element matching pattern
+/// @param array
+/// @param callback pattern
+/// @returns index of element
+var findIndex = function (array, callback) {
+    var end = false;
+    var i = 0;
+    for (; i < array.length && !end; i++) {
+        end = callback(array[i]);
+    }
+    return end ? i - 1 : -1;
+};
+
+/// @returns ascii string representation of hex value prefixed with 0x
+var toAscii = function(hex) {
+// Find termination
+    var str = "";
+    var i = 0, l = hex.length;
+    if (hex.substring(0, 2) === '0x') {
+        i = 2;
+    }
+    for (; i < l; i+=2) {
+        var code = parseInt(hex.substr(i, 2), 16);
+        if (code === 0) {
+            break;
+        }
+
+        str += String.fromCharCode(code);
+    }
+
+    return str;
+};
+    
+var toHex = function(str) {
+    var hex = "";
+    for(var i = 0; i < str.length; i++) {
+        var n = str.charCodeAt(i).toString(16);
+        hex += n.length < 2 ? '0' + n : n;
+    }
+
+    return hex;
+};
+
+/// @returns hex representation (prefixed by 0x) of ascii string
+var fromAscii = function(str, pad) {
+    pad = pad === undefined ? 0 : pad;
+    var hex = toHex(str);
+    while (hex.length < pad*2)
+        hex += "00";
+    return "0x" + hex;
+};
+
+/// @returns display name for function/event eg. multiply(uint256) -> multiply
+var extractDisplayName = function (name) {
+    var length = name.indexOf('('); 
+    return length !== -1 ? name.substr(0, length) : name;
+};
+
+/// @returns overloaded part of function/event name
+var extractTypeName = function (name) {
+    /// TODO: make it invulnerable
+    var length = name.indexOf('(');
+    return length !== -1 ? name.substr(length + 1, name.length - 1 - (length + 1)) : "";
+};
+
+/// Filters all function from input abi
+/// @returns abi array with filtered objects of type 'function'
+var filterFunctions = function (json) {
+    return json.filter(function (current) {
+        return current.type === 'function'; 
+    }); 
+};
+
+/// Filters all events form input abi
+/// @returns abi array with filtered objects of type 'event'
+var filterEvents = function (json) {
+    return json.filter(function (current) {
+        return current.type === 'event';
+    });
+};
+
+module.exports = {
+    findIndex: findIndex,
+    toAscii: toAscii,
+    fromAscii: fromAscii,
+    extractDisplayName: extractDisplayName,
+    extractTypeName: extractTypeName,
+    filterFunctions: filterFunctions,
+    filterEvents: filterEvents
+};
+