首次放到 git

2018-10-09 23:03:05 +08:00
commit 16cca302b7
37 changed files with 4203 additions and 0 deletions
--- a/utils/units.js
+++ b/utils/units.js
@@ -0,0 +1,148 @@
+var bigNumberify = require('./bignumber.js').bigNumberify;
+var throwError = require('./throw-error');
+
+var zero = new bigNumberify(0);
+var negative1 = new bigNumberify(-1);
+
+var names = [
+    'wei',
+    'kwei',
+    'Mwei',
+    'Gwei',
+    'szabo',
+    'finny',
+    'ether',
+];
+
+var getUnitInfo = (function() {
+    var unitInfos = {};
+
+    function getUnitInfo(value) {
+        return {
+            decimals: value.length - 1,
+            tenPower: bigNumberify(value)
+        };
+    }
+
+    // Cache the common units
+    var value = '1';
+    names.forEach(function(name) {
+        var info = getUnitInfo(value);
+        unitInfos[name.toLowerCase()] = info;
+        unitInfos[String(info.decimals)] = info;
+        value += '000';
+    });
+
+    return function(name) {
+        // Try the cache
+        var info = unitInfos[String(name).toLowerCase()];
+
+        if (!info && typeof(name) === 'number' && parseInt(name) == name && name >= 0 && name <= 256) {
+            var value = '1';
+            for (var i = 0; i < name; i++) { value += '0'; }
+            info = getUnitInfo(value);
+        }
+
+        // Make sure we got something
+        if (!info) { throwError('invalid unitType', { unitType: name }); }
+
+        return info;
+    }
+})();
+
+function formatUnits(value, unitType, options) {
+    if (typeof(unitType) === 'object' && !options) {
+        options = unitType;
+        unitType = undefined;
+    }
+
+    if (unitType == null) { unitType = 18; }
+    var unitInfo = getUnitInfo(unitType);
+
+    // Make sure wei is a big number (convert as necessary)
+    value = bigNumberify(value);
+
+    if (!options) { options = {}; }
+
+    var negative = value.lt(zero);
+    if (negative) { value = value.mul(negative1); }
+
+    var fraction = value.mod(unitInfo.tenPower).toString(10);
+    while (fraction.length < unitInfo.decimals) { fraction = '0' + fraction; }
+
+    // Strip off trailing zeros (but keep one if would otherwise be bare decimal point)
+    if (!options.pad) {
+        fraction = fraction.match(/^([0-9]*[1-9]|0)(0*)/)[1];
+    }
+
+    var whole = value.div(unitInfo.tenPower).toString(10);
+
+    if (options.commify) {
+        whole = whole.replace(/\B(?=(\d{3})+(?!\d))/g, ",")
+    }
+
+    var value = whole + '.' + fraction;
+
+    if (negative) { value = '-' + value; }
+
+    return value;
+}
+
+function parseUnits(value, unitType) {
+    if (unitType == null) { unitType = 18; }
+    var unitInfo = getUnitInfo(unitType);
+
+    if (typeof(value) !== 'string' || !value.match(/^-?[0-9.,]+$/)) {
+        throwError('invalid value', { input: value });
+    }
+
+    // Remove commas
+    var value = value.replace(/,/g,'');
+
+    // Is it negative?
+    var negative = (value.substring(0, 1) === '-');
+    if (negative) { value = value.substring(1); }
+
+    if (value === '.') { throwError('invalid value', { input: value }); }
+
+    // Split it into a whole and fractional part
+    var comps = value.split('.');
+    if (comps.length > 2) { throwError('too many decimal points', { input: value }); }
+
+    var whole = comps[0], fraction = comps[1];
+    if (!whole) { whole = '0'; }
+    if (!fraction) { fraction = '0'; }
+
+    // Prevent underflow
+    if (fraction.length > unitInfo.decimals) {
+        throwError('too many decimal places', { input: value, decimals: fraction.length });
+    }
+
+    // Fully pad the string with zeros to get to wei
+    while (fraction.length < unitInfo.decimals) { fraction += '0'; }
+
+    whole = bigNumberify(whole);
+    fraction = bigNumberify(fraction);
+
+    var wei = (whole.mul(unitInfo.tenPower)).add(fraction);
+
+    if (negative) { wei = wei.mul(negative1); }
+
+    return wei;
+}
+
+function formatEther(wei, options) {
+    return formatUnits(wei, 18, options);
+}
+
+function parseEther(ether) {
+    return parseUnits(ether, 18);
+}
+
+module.exports = {
+    formatEther: formatEther,
+    parseEther: parseEther,
+
+    formatUnits: formatUnits,
+    parseUnits: parseUnits,
+}