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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.// Copyright the Browserify authors. MIT License.// Ported from https://github.com/browserify/path-browserify/// This module is browser compatible.
import { CHAR_DOT, CHAR_FORWARD_SLASH } from "./constants.ts";
// Resolves . and .. elements in a path with directory namesexport function normalizeString(  path: string,  allowAboveRoot: boolean,  separator: string,  isPathSeparator: (code: number) => boolean,): string {  let res = "";  let lastSegmentLength = 0;  let lastSlash = -1;  let dots = 0;  let code: number | undefined;  for (let i = 0; i <= path.length; ++i) {    if (i < path.length) code = path.charCodeAt(i);    else if (isPathSeparator(code!)) break;    else code = CHAR_FORWARD_SLASH;
    if (isPathSeparator(code!)) {      if (lastSlash === i - 1 || dots === 1) {        // NOOP      } else if (lastSlash !== i - 1 && dots === 2) {        if (          res.length < 2 ||          lastSegmentLength !== 2 ||          res.charCodeAt(res.length - 1) !== CHAR_DOT ||          res.charCodeAt(res.length - 2) !== CHAR_DOT        ) {          if (res.length > 2) {            const lastSlashIndex = res.lastIndexOf(separator);            if (lastSlashIndex === -1) {              res = "";              lastSegmentLength = 0;            } else {              res = res.slice(0, lastSlashIndex);              lastSegmentLength = res.length - 1 - res.lastIndexOf(separator);            }            lastSlash = i;            dots = 0;            continue;          } else if (res.length === 2 || res.length === 1) {            res = "";            lastSegmentLength = 0;            lastSlash = i;            dots = 0;            continue;          }        }        if (allowAboveRoot) {          if (res.length > 0) res += `${separator}..`;          else res = "..";          lastSegmentLength = 2;        }      } else {        if (res.length > 0) res += separator + path.slice(lastSlash + 1, i);        else res = path.slice(lastSlash + 1, i);        lastSegmentLength = i - lastSlash - 1;      }      lastSlash = i;      dots = 0;    } else if (code === CHAR_DOT && dots !== -1) {      ++dots;    } else {      dots = -1;    }  }  return res;}