locutus
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Locutus other languages' standard libraries to JavaScript for fun and educational purposes
108 lines (107 loc) • 3.48 kB
JavaScript
import { _phpCastString } from "../_helpers/_phpCastString.js";
export function strnatcmp(left, right) {
// discuss at: https://locutus.io/php/strnatcmp/
// parity verified: PHP 8.3
// original by: Martijn Wieringa
// improved by: Michael White (https://getsprink.com)
// improved by: Jack
// bugfixed by: Onno Marsman (https://twitter.com/onnomarsman)
// reimplemented by: Rafał Kukawski
// example 1: strnatcmp('abc', 'abc')
// returns 1: 0
// example 2: strnatcmp('a', 'b')
// returns 2: -1
// example 3: strnatcmp('10', '1')
// returns 3: 1
// example 4: strnatcmp('0000abc', '0abc')
// returns 4: 0
// example 5: strnatcmp('1239', '12345')
// returns 5: -1
// example 6: strnatcmp('t01239', 't012345')
// returns 6: 1
// example 7: strnatcmp('0A', '5N')
// returns 7: -1
const leadingZeros = /^0+(?=\d)/;
const whitespace = /^\s/;
const digit = /^\d/;
let leftValue = _phpCastString(left);
let rightValue = _phpCastString(right);
if (!leftValue.length || !rightValue.length) {
return leftValue.length - rightValue.length;
}
let i = 0;
let j = 0;
leftValue = leftValue.replace(leadingZeros, '');
rightValue = rightValue.replace(leadingZeros, '');
while (i < leftValue.length && j < rightValue.length) {
// skip consecutive whitespace
while (whitespace.test(leftValue.charAt(i))) {
i++;
}
while (whitespace.test(rightValue.charAt(j))) {
j++;
}
let ac = leftValue.charAt(i);
let bc = rightValue.charAt(j);
let aIsDigit = digit.test(ac);
let bIsDigit = digit.test(bc);
if (aIsDigit && bIsDigit) {
let bias = 0;
const fractional = ac === '0' || bc === '0';
do {
if (!aIsDigit) {
return -1;
}
else if (!bIsDigit) {
return 1;
}
else if (ac < bc) {
if (!bias) {
bias = -1;
}
if (fractional) {
return -1;
}
}
else if (ac > bc) {
if (!bias) {
bias = 1;
}
if (fractional) {
return 1;
}
}
ac = leftValue.charAt(++i);
bc = rightValue.charAt(++j);
aIsDigit = digit.test(ac);
bIsDigit = digit.test(bc);
} while (aIsDigit || bIsDigit);
if (!fractional && bias) {
return bias;
}
continue;
}
if (!ac || !bc) {
continue;
}
else if (ac < bc) {
return -1;
}
else if (ac > bc) {
return 1;
}
i++;
j++;
}
const iBeforeStrEnd = i < leftValue.length;
const jBeforeStrEnd = j < rightValue.length;
// Check which string ended first
// return -1 if a, 1 if b, 0 otherwise
if (iBeforeStrEnd && !jBeforeStrEnd) {
return 1;
}
if (!iBeforeStrEnd && jBeforeStrEnd) {
return -1;
}
return 0;
}