index.js

@@ -159,20 +159,43 @@ Utils.prototype.Log = function Log(options) {
 };
 
 /**
- * Genereates a string into an unsigned int
+ * Hash string into another string (A-Z, 0-9)
  *
- * @param {string} str The string to convert
- * @return {number} the hashed value
+ * @param {string} str The string to hash
+ * @param {string} length Length of result string
+ * @return {string} The hashed result string
  */
-Utils.prototype.hashUnsignedIntFromString = function hashUnsignedIntFromString(str) {
-	let hash = 0;
+Utils.prototype.hashStringToString = function hashStringToString(str, length) {
+	if (length === 0) return '';
 
-	if (str.length === 0) return hash;
+	const base = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
+	const resultIndices = new Array(length);
+
+	// Generate an index salt so that similar input strings will give different result strings
+	let indexSalt = 0;
 	for (let i = 0; i < str.length; i++) {
-		hash += (1 << str.charCodeAt(i)) >>> 0;
+		indexSalt += (1 << str.charCodeAt(i)) >>> 0;
+	}
+
+	if (str.length >= length) {
+		// Input string is longer or same length as desired result string length
+		for (let i = 0; i < str.length; ++i) {
+			const resultIndex = i % length;
+			const valueIndex = Math.abs(((resultIndices[resultIndex] ? resultIndices[resultIndex] : 0) + ((1 << str.charCodeAt(i))) + indexSalt + i) % base.length);
+			resultIndices[resultIndex] = valueIndex;
+		}
+	} else {
+		// Result string string is longer than the input string
+		for (let i = 0; i < resultIndices.length; ++i) {
+			const resultIndex = i;
+			const valueIndex = Math.abs((((1 << str.charCodeAt(i % str.length)) * i) + indexSalt) % base.length);
+			resultIndices[resultIndex] = valueIndex;
+		}
 	}
 
-	return hash;
+	const result = resultIndices.map(x => base[x]).join('');
+
+	return result;
 };
 
 Utils.prototype.Log.prototype.stdout = function stdout(lvl, msg) {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "larvitutils",
-  "version": "2.3.1",
+  "version": "2.3.2",
   "description": "Misc utils",
   "main": "index.js",
   "devDependencies": {

test/hashStringToString.js

@@ -0,0 +1,49 @@
+'use strict';
+
+const test = require('tape');
+const utils = new (require(__dirname + '/../index.js'))();
+
+test('hashStringToString() - Hash string to string of length 0', t => {
+	t.equal(utils.hashStringToString('asdf', 0), '');
+	t.end();
+});
+
+test('hashStringToString() - Hash string to string of length 1', t => {
+	t.equal(utils.hashStringToString('asdf', 1).length, 1);
+	t.end();
+});
+
+test('hashStringToString() - Hash string to string of length 2', t => {
+	t.equal(utils.hashStringToString('asdf', 2).length, 2);
+	t.end();
+});
+
+test('hashStringToString() - Hash string to string give the same output when input is the same', t => {
+	const first = utils.hashStringToString('asdf', 1);
+
+	t.equal(utils.hashStringToString('asdf', 1), first);
+	t.equal(utils.hashStringToString('asdf', 1), first);
+	t.equal(utils.hashStringToString('asdf', 1), first);
+	t.equal(utils.hashStringToString('asdf', 1), first);
+	t.end();
+});
+
+test('hashStringToString() - Hash string to string where result string length is longer than input string length', t => {
+	t.equal(utils.hashStringToString('nisse', 20).length, 20);
+	t.end();
+});
+
+test('hashStringToString() - Hash similar string should give different results', t => {
+	t.notEqual(utils.hashStringToString('nisse1', 6), utils.hashStringToString('nisse2', 6));
+	utils.hashStringToString('pisse1', 6);
+	t.end();
+});
+
+test('hashStringToString() - Hash string where all characters are the same should result in string where all characters are not the same', t => {
+	const result = utils.hashStringToString('aaaaa', 6);
+	const resultAsArray = result.split('');
+
+	t.notEqual(resultAsArray.filter(x => x === resultAsArray[0]).length, resultAsArray.length);
+
+	t.end();
+});