lib/path.js
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
'use strict';
var isWindows = process.platform === 'win32';
var util = require('util');
// resolves . and .. elements in a path array with directory names there
// must be no slashes or device names (c:\) in the array
// (so also no leading and trailing slashes - it does not distinguish
// relative and absolute paths)
function normalizeArray(parts, allowAboveRoot) {
var res = [];
for (var i = 0; i < parts.length; i++) {
var p = parts[i];
// ignore empty parts
if (!p || p === '.')
continue;
if (p === '..') {
if (res.length && res[res.length - 1] !== '..') {
res.pop();
} else if (allowAboveRoot) {
res.push('..');
}
} else {
res.push(p);
}
}
return res;
}
// returns an array with empty elements removed from either end of the input
// array or the original array if no elements need to be removed
function trimArray(arr) {
var lastIndex = arr.length - 1;
var start = 0;
for (; start <= lastIndex; start++) {
if (arr[start])
break;
}
var end = lastIndex;
for (; end >= 0; end--) {
if (arr[end])
break;
}
if (start === 0 && end === lastIndex)
return arr;
if (start > end)
return [];
return arr.slice(start, end + 1);
}
// Regex to split a windows path into three parts: [*, device, slash,
// tail] windows-only
var splitDeviceRe =
/^([a-zA-Z]:|[\\\/]{2}[^\\\/]+[\\\/]+[^\\\/]+)?([\\\/])?([\s\S]*?)$/;
// Regex to split the tail part of the above into [*, dir, basename, ext]
var splitTailRe =
/^([\s\S]*?)((?:\.{1,2}|[^\\\/]+?|)(\.[^.\/\\]*|))(?:[\\\/]*)$/;
var win32 = {};
// Function to split a filename into [root, dir, basename, ext]
function win32SplitPath(filename) {
// Separate device+slash from tail
var result = splitDeviceRe.exec(filename),
device = (result[1] || '') + (result[2] || ''),
tail = result[3] || '';
// Split the tail into dir, basename and extension
var result2 = splitTailRe.exec(tail),
dir = result2[1],
basename = result2[2],
ext = result2[3];
return [device, dir, basename, ext];
}
function win32StatPath(path) {
var result = splitDeviceRe.exec(path),
device = result[1] || '',
isUnc = !!device && device[1] !== ':';
return {
device: device,
isUnc: isUnc,
isAbsolute: isUnc || !!result[2], // UNC paths are always absolute
tail: result[3]
};
}
function normalizeUNCRoot(device) {
return '\\\\' + device.replace(/^[\\\/]+/, '').replace(/[\\\/]+/g, '\\');
}
// path.resolve([from ...], to)
win32.resolve = function() {
var resolvedDevice = '',
resolvedTail = '',
resolvedAbsolute = false;
for (var i = arguments.length - 1; i >= -1; i--) {
var path;
if (i >= 0) {
path = arguments[i];
} else if (!resolvedDevice) {
path = process.cwd();
} else {
// Windows has the concept of drive-specific current working
// directories. If we've resolved a drive letter but not yet an
// absolute path, get cwd for that drive. We're sure the device is not
// an unc path at this points, because unc paths are always absolute.
path = process.env['=' + resolvedDevice];
// Verify that a drive-local cwd was found and that it actually points
// to our drive. If not, default to the drive's root.
if (!path || path.substr(0, 3).toLowerCase() !==
resolvedDevice.toLowerCase() + '\\') {
path = resolvedDevice + '\\';
}
}
// Skip empty and invalid entries
if (!util.isString(path)) {
throw new TypeError('Arguments to path.resolve must be strings');
} else if (!path) {
continue;
}
var result = win32StatPath(path),
device = result.device,
isUnc = result.isUnc,
isAbsolute = result.isAbsolute,
tail = result.tail;
if (device &&
resolvedDevice &&
device.toLowerCase() !== resolvedDevice.toLowerCase()) {
// This path points to another device so it is not applicable
continue;
}
if (!resolvedDevice) {
resolvedDevice = device;
}
if (!resolvedAbsolute) {
resolvedTail = tail + '\\' + resolvedTail;
resolvedAbsolute = isAbsolute;
}
if (resolvedDevice && resolvedAbsolute) {
break;
}
}
// Convert slashes to backslashes when `resolvedDevice` points to an UNC
// root. Also squash multiple slashes into a single one where appropriate.
if (isUnc) {
resolvedDevice = normalizeUNCRoot(resolvedDevice);
}
// At this point the path should be resolved to a full absolute path,
// but handle relative paths to be safe (might happen when process.cwd()
// fails)
// Normalize the tail path
resolvedTail = normalizeArray(resolvedTail.split(/[\\\/]+/),
!resolvedAbsolute).join('\\');
return (resolvedDevice + (resolvedAbsolute ? '\\' : '') + resolvedTail) ||
'.';
};
win32.normalize = function(path) {
var result = win32StatPath(path),
device = result.device,
isUnc = result.isUnc,
isAbsolute = result.isAbsolute,
tail = result.tail,
trailingSlash = /[\\\/]$/.test(tail);
// Normalize the tail path
tail = normalizeArray(tail.split(/[\\\/]+/), !isAbsolute).join('\\');
if (!tail && !isAbsolute) {
tail = '.';
}
if (tail && trailingSlash) {
tail += '\\';
}
// Convert slashes to backslashes when `device` points to an UNC root.
// Also squash multiple slashes into a single one where appropriate.
if (isUnc) {
device = normalizeUNCRoot(device);
}
return device + (isAbsolute ? '\\' : '') + tail;
};
win32.isAbsolute = function(path) {
return win32StatPath(path).isAbsolute;
};
win32.join = function() {
var paths = [];
for (var i = 0; i < arguments.length; i++) {
var arg = arguments[i];
if (!util.isString(arg)) {
throw new TypeError('Arguments to path.join must be strings');
}
if (arg) {
paths.push(arg);
}
}
var joined = paths.join('\\');
// 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\')
if (!/^[\\\/]{2}[^\\\/]/.test(paths[0])) {
joined = joined.replace(/^[\\\/]{2,}/, '\\');
}
return win32.normalize(joined);
};
// path.relative(from, to)
// it will solve the relative path from 'from' to 'to', for instance:
// from = 'C:\\orandea\\test\\aaa'
// to = 'C:\\orandea\\impl\\bbb'
// The output of the function should be: '..\\..\\impl\\bbb'
win32.relative = function(from, to) {
from = win32.resolve(from);
to = win32.resolve(to);
// windows is not case sensitive
var lowerFrom = from.toLowerCase();
var lowerTo = to.toLowerCase();
var toParts = trimArray(to.split('\\'));
var lowerFromParts = trimArray(lowerFrom.split('\\'));
var lowerToParts = trimArray(lowerTo.split('\\'));
var length = Math.min(lowerFromParts.length, lowerToParts.length);
var samePartsLength = length;
for (var i = 0; i < length; i++) {
if (lowerFromParts[i] !== lowerToParts[i]) {
samePartsLength = i;
break;
}
}
if (samePartsLength == 0) {
return to;
}
var outputParts = [];
for (var i = samePartsLength; i < lowerFromParts.length; i++) {
outputParts.push('..');
}
outputParts = outputParts.concat(toParts.slice(samePartsLength));
return outputParts.join('\\');
};
win32._makeLong = function(path) {
// Note: this will *probably* throw somewhere.
if (!util.isString(path))
return path;
if (!path) {
return '';
}
var resolvedPath = win32.resolve(path);
if (/^[a-zA-Z]\:\\/.test(resolvedPath)) {
// path is local filesystem path, which needs to be converted
// to long UNC path.
return '\\\\?\\' + resolvedPath;
} else if (/^\\\\[^?.]/.test(resolvedPath)) {
// path is network UNC path, which needs to be converted
// to long UNC path.
return '\\\\?\\UNC\\' + resolvedPath.substring(2);
}
return path;
};
win32.dirname = function(path) {
var result = win32SplitPath(path),
root = result[0],
dir = result[1];
if (!root && !dir) {
// No dirname whatsoever
return '.';
}
if (dir) {
// It has a dirname, strip trailing slash
dir = dir.substr(0, dir.length - 1);
}
return root + dir;
};
win32.basename = function(path, ext) {
var f = win32SplitPath(path)[2];
// TODO: make this comparison case-insensitive on windows?
if (ext && f.substr(-1 * ext.length) === ext) {
f = f.substr(0, f.length - ext.length);
}
return f;
};
win32.extname = function(path) {
return win32SplitPath(path)[3];
};
win32.format = function(pathObject) {
if (!util.isObject(pathObject)) {
throw new TypeError(
"Parameter 'pathObject' must be an object, not " + typeof pathObject
);
}
var root = pathObject.root || '';
if (!util.isString(root)) {
throw new TypeError(
"'pathObject.root' must be a string or undefined, not " +
typeof pathObject.root
);
}
var dir = pathObject.dir;
var base = pathObject.base || '';
if (!dir) {
return base;
}
if (dir[dir.length - 1] === win32.sep) {
return dir + base;
}
return dir + win32.sep + base;
};
win32.parse = function(pathString) {
if (!util.isString(pathString)) {
throw new TypeError(
"Parameter 'pathString' must be a string, not " + typeof pathString
);
}
var allParts = win32SplitPath(pathString);
if (!allParts || allParts.length !== 4) {
throw new TypeError("Invalid path '" + pathString + "'");
}
return {
root: allParts[0],
dir: allParts[0] + allParts[1].slice(0, -1),
base: allParts[2],
ext: allParts[3],
name: allParts[2].slice(0, allParts[2].length - allParts[3].length)
};
};
win32.sep = '\\';
win32.delimiter = ';';
// Split a filename into [root, dir, basename, ext], unix version
// 'root' is just a slash, or nothing.
var splitPathRe =
/^(\/?|)([\s\S]*?)((?:\.{1,2}|[^\/]+?|)(\.[^.\/]*|))(?:[\/]*)$/;
var posix = {};
function posixSplitPath(filename) {
return splitPathRe.exec(filename).slice(1);
}
// path.resolve([from ...], to)
// posix version
posix.resolve = function() {
var resolvedPath = '',
resolvedAbsolute = false;
for (var i = arguments.length - 1; i >= -1 && !resolvedAbsolute; i--) {
var path = (i >= 0) ? arguments[i] : process.cwd();
// Skip empty and invalid entries
if (!util.isString(path)) {
throw new TypeError('Arguments to path.resolve must be strings');
} else if (!path) {
continue;
}
resolvedPath = path + '/' + resolvedPath;
resolvedAbsolute = path[0] === '/';
}
// At this point the path should be resolved to a full absolute path, but
// handle relative paths to be safe (might happen when process.cwd() fails)
// Normalize the path
resolvedPath = normalizeArray(resolvedPath.split('/'),
!resolvedAbsolute).join('/');
return ((resolvedAbsolute ? '/' : '') + resolvedPath) || '.';
};
// path.normalize(path)
// posix version
posix.normalize = function(path) {
var isAbsolute = posix.isAbsolute(path),
trailingSlash = path && path[path.length - 1] === '/';
// Normalize the path
path = normalizeArray(path.split('/'), !isAbsolute).join('/');
if (!path && !isAbsolute) {
path = '.';
}
if (path && trailingSlash) {
path += '/';
}
return (isAbsolute ? '/' : '') + path;
};
// posix version
posix.isAbsolute = function(path) {
return path.charAt(0) === '/';
};
// posix version
posix.join = function() {
var path = '';
for (var i = 0; i < arguments.length; i++) {
var segment = arguments[i];
if (!util.isString(segment)) {
throw new TypeError('Arguments to path.join must be strings');
}
if (segment) {
if (!path) {
path += segment;
} else {
path += '/' + segment;
}
}
}
return posix.normalize(path);
};
// path.relative(from, to)
// posix version
posix.relative = function(from, to) {
from = posix.resolve(from).substr(1);
to = posix.resolve(to).substr(1);
var fromParts = trimArray(from.split('/'));
var toParts = trimArray(to.split('/'));
var length = Math.min(fromParts.length, toParts.length);
var samePartsLength = length;
for (var i = 0; i < length; i++) {
if (fromParts[i] !== toParts[i]) {
samePartsLength = i;
break;
}
}
var outputParts = [];
for (var i = samePartsLength; i < fromParts.length; i++) {
outputParts.push('..');
}
outputParts = outputParts.concat(toParts.slice(samePartsLength));
return outputParts.join('/');
};
posix._makeLong = function(path) {
return path;
};
posix.dirname = function(path) {
var result = posixSplitPath(path),
root = result[0],
dir = result[1];
if (!root && !dir) {
// No dirname whatsoever
return '.';
}
if (dir) {
// It has a dirname, strip trailing slash
dir = dir.substr(0, dir.length - 1);
}
return root + dir;
};
posix.basename = function(path, ext) {
var f = posixSplitPath(path)[2];
// TODO: make this comparison case-insensitive on windows?
if (ext && f.substr(-1 * ext.length) === ext) {
f = f.substr(0, f.length - ext.length);
}
return f;
};
posix.extname = function(path) {
return posixSplitPath(path)[3];
};
posix.format = function(pathObject) {
if (!util.isObject(pathObject)) {
throw new TypeError(
"Parameter 'pathObject' must be an object, not " + typeof pathObject
);
}
var root = pathObject.root || '';
if (!util.isString(root)) {
throw new TypeError(
"'pathObject.root' must be a string or undefined, not " +
typeof pathObject.root
);
}
var dir = pathObject.dir ? pathObject.dir + posix.sep : '';
var base = pathObject.base || '';
return dir + base;
};
posix.parse = function(pathString) {
if (!util.isString(pathString)) {
throw new TypeError(
"Parameter 'pathString' must be a string, not " + typeof pathString
);
}
var allParts = posixSplitPath(pathString);
if (!allParts || allParts.length !== 4) {
throw new TypeError("Invalid path '" + pathString + "'");
}
allParts[1] = allParts[1] || '';
allParts[2] = allParts[2] || '';
allParts[3] = allParts[3] || '';
return {
root: allParts[0],
dir: allParts[0] + allParts[1].slice(0, -1),
base: allParts[2],
ext: allParts[3],
name: allParts[2].slice(0, allParts[2].length - allParts[3].length)
};
};
posix.sep = '/';
posix.delimiter = ':';
if (isWindows)
module.exports = win32;
else /* posix */
module.exports = posix;
module.exports.posix = posix;
module.exports.win32 = win32;