43 lines
1.0 KiB
JavaScript
43 lines
1.0 KiB
JavaScript
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"use strict";
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var isValue = require("../object/is-value")
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, toNaturalNumber = require("../number/to-pos-integer");
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var generated = Object.create(null), random = Math.random, uniqTryLimit = 100;
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var getChunk = function () {
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return random()
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.toString(36)
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.slice(2);
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};
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var getString = function (/* length */) {
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var str = getChunk(), length = arguments[0];
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if (!isValue(length)) return str;
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while (str.length < length) str += getChunk();
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return str.slice(0, length);
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};
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module.exports = function (/* options */) {
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var options = Object(arguments[0]), length = options.length, isUnique = options.isUnique;
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if (isValue(length)) length = toNaturalNumber(length);
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var str = getString(length);
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if (isUnique) {
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var count = 0;
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while (generated[str]) {
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if (++count === uniqTryLimit) {
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throw new Error(
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"Cannot generate random string.\n" +
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"String.random is not designed to effectively generate many short and " +
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"unique random strings"
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);
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}
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str = getString(length);
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}
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generated[str] = true;
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}
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return str;
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};
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