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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.// This module is browser compatible.
import { assertArg } from "../_common/dirname.ts";import { stripTrailingSeparators } from "../_common/strip_trailing_separators.ts";import { isPosixPathSeparator } from "./_util.ts";
/** * Return the directory path of a `path`. * @param path - path to extract the directory from. */export function dirname(path: string): string {  assertArg(path);
  let end = -1;  let matchedNonSeparator = false;
  for (let i = path.length - 1; i >= 1; --i) {    if (isPosixPathSeparator(path.charCodeAt(i))) {      if (matchedNonSeparator) {        end = i;        break;      }    } else {      matchedNonSeparator = true;    }  }
  // No matches. Fallback based on provided path:  //  // - leading slashes paths  //     "/foo" => "/"  //     "///foo" => "/"  // - no slash path  //     "foo" => "."  if (end === -1) {    return isPosixPathSeparator(path.charCodeAt(0)) ? "/" : ".";  }
  return stripTrailingSeparators(    path.slice(0, end),    isPosixPathSeparator,  );}