// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.// This module is browser compatible. import{ assert }from"../../assert/assert.ts";import{ assertPath }from"../_common/assert_path.ts";import{ isPathSeparator }from"./_util.ts";import{ normalize }from"./normalize.ts"; /** * Join all given a sequence of `paths`,then normalizes the resulting path. * @param paths to be joined and normalized */exportfunctionjoin(...paths:string[]):string{if(paths.length===0)return"."; let joined:string|undefined;let firstPart:string|null=null;for(let i =0; i < paths.length;++i){const path = paths[i];assertPath(path);if(path.length>0){if(joined ===undefined) joined = firstPart = path;else joined +=`\\${path}`;}} if(joined ===undefined)return"."; // Make sure that the joined path doesn't start with two slashes, because// normalize() will mistake it for an UNC path then.//// This step is skipped when it is very clear that the user actually// intended to point at an UNC path. This is assumed when the first// non-empty string arguments starts with exactly two slashes followed by// at least one more non-slash character.//// Note that for normalize() to treat a path as an UNC path it needs to// have at least 2 components, so we don't filter for that here.// This means that the user can use join to construct UNC paths from// a server name and a share name; for example:// path.join('//server', 'share') -> '\\\\server\\share\\')let needsReplace =true;let slashCount =0;assert(firstPart !==null);if(isPathSeparator(firstPart.charCodeAt(0))){++slashCount;const firstLen = firstPart.length;if(firstLen >1){if(isPathSeparator(firstPart.charCodeAt(1))){++slashCount;if(firstLen >2){if(isPathSeparator(firstPart.charCodeAt(2)))++slashCount;else{// We matched a UNC path in the first part needsReplace =false;}}}}}if(needsReplace){// Find any more consecutive slashes we need to replacefor(; slashCount < joined.length;++slashCount){if(!isPathSeparator(joined.charCodeAt(slashCount)))break;} // Replace the slashes if neededif(slashCount >=2) joined =`\\${joined.slice(slashCount)}`;} returnnormalize(joined);}