locutus/esm/php/array/array_splice.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

import { is_int as isInt } from "../var/is_int.js";
const isAssocArray = (value) => typeof value === 'object' && value !== null && !Array.isArray(value);
const toReplacementItems = (replacement) => {
    if (typeof replacement === 'undefined') {
        return undefined;
    }
    if (Array.isArray(replacement)) {
        return replacement.slice();
    }
    if (isAssocArray(replacement)) {
        const values = [];
        for (const key in replacement) {
            values.push(replacement[key]);
        }
        return values;
    }
    return [replacement];
};
const checkToUpIndices = (assoc, cursor, key) => {
    // Deal with situation, e.g., if encounter index 4 and try
    // to set it to 0, but 0 exists later in loop (need to
    // increment all subsequent (skipping current key,
    // since we need its value below) until find unused)
    if (assoc[String(cursor)] !== undefined) {
        const tmp = cursor;
        cursor += 1;
        if (cursor === Number.parseInt(key, 10)) {
            cursor += 1;
        }
        cursor = checkToUpIndices(assoc, cursor, key);
        assoc[String(cursor)] = assoc[String(tmp)];
        delete assoc[String(tmp)];
    }
    return cursor;
};
export function array_splice(arr, offst, lgth, replacement) {
    //      discuss at: https://locutus.io/php/array_splice/
    // parity verified: PHP 8.3
    //     original by: Brett Zamir (https://brett-zamir.me)
    //        input by: Theriault (https://github.com/Theriault)
    //          note 1: Order does get shifted in associative array input with numeric indices,
    //          note 1: since PHP behavior doesn't preserve keys, but I understand order is
    //          note 1: not reliable anyways
    //          note 1: Note also that IE retains information about property position even
    //          note 1: after being supposedly deleted, so use of this function may produce
    //          note 1: unexpected results in IE if you later attempt to add back properties
    //          note 1: with the same keys that had been deleted
    //       example 1: var $input = ["red", "green", "blue", "yellow"]
    //       example 1: array_splice($input, 2)
    //       returns 1: ["blue", "yellow"]
    //       example 2: var $input = ["red", "green", "blue", "yellow"]
    //       example 2: array_splice($input, 3, 0, "purple")
    //       returns 2: []
    //       example 3: var $input = ["red", "green", "blue", "yellow"]
    //       example 3: array_splice($input, -1, 1, ["black", "maroon"])
    //       returns 3: ["yellow"]
    const replacementItems = toReplacementItems(replacement);
    const sourceLength = Array.isArray(arr) ? arr.length : Object.keys(arr).length;
    const lengthToRemove = typeof lgth === 'undefined'
        ? offst >= 0
            ? sourceLength - offst
            : -offst
        : lgth < 0
            ? (offst >= 0 ? sourceLength - offst : -offst) + lgth
            : lgth;
    if (Array.isArray(arr)) {
        const arrayInput = arr;
        if (replacementItems) {
            return arrayInput.splice(offst, lengthToRemove, ...replacementItems);
        }
        return arrayInput.splice(offst, lengthToRemove);
    }
    let totalLength = 0;
    let indexCursor = -1;
    let replacementCursor = 0;
    let numericCursor = -1;
    let returnsArray = true;
    let removedNumericCursor = 0;
    const removedItems = [];
    const removedAssoc = {};
    const assoc = arr;
    for (const _key in assoc) {
        totalLength += 1;
    }
    const normalizedOffset = offst >= 0 ? offst : totalLength + offst;
    for (const key in assoc) {
        indexCursor += 1;
        if (indexCursor < normalizedOffset) {
            if (isInt(key)) {
                numericCursor += 1;
                if (Number.parseInt(key, 10) !== numericCursor) {
                    checkToUpIndices(assoc, numericCursor, key);
                    assoc[String(numericCursor)] = assoc[key];
                    delete assoc[key];
                }
            }
            continue;
        }
        if (returnsArray && isInt(key)) {
            removedItems.push(assoc[key]);
            removedAssoc[String(removedNumericCursor)] = assoc[key];
            removedNumericCursor += 1;
        }
        else {
            removedAssoc[key] = assoc[key];
            returnsArray = false;
        }
        if (replacementItems && replacementCursor < replacementItems.length) {
            assoc[key] = replacementItems[replacementCursor];
            replacementCursor += 1;
        }
        else {
            delete assoc[key];
        }
    }
    return returnsArray ? removedItems : removedAssoc;
}