docs: add linkback in README

.gitignore

@@ -0,0 +1,21 @@
+.env
+*.gz
+.*.sw*
+.ignore
+
+*.pem
+
+# Logs
+logs
+*.log
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# Dependency directory
+# https://www.npmjs.org/doc/misc/npm-faq.html#should-i-check-my-node_modules-folder-into-git
+
+node_modules

AUTHORS

@@ -0,0 +1 @@
+AJ ONeal <coolaj86@gmail.com> (https://coolaj86.com)

LICENSE

@@ -0,0 +1,375 @@
+Copyright 2020 AJ ONeal
+
+Mozilla Public License Version 2.0
+==================================
+
+1. Definitions
+--------------
+
+1.1. "Contributor"
+    means each individual or legal entity that creates, contributes to
+    the creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+    means the combination of the Contributions of others (if any) used
+    by a Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+    means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+    means Source Code Form to which the initial Contributor has attached
+    the notice in Exhibit A, the Executable Form of such Source Code
+    Form, and Modifications of such Source Code Form, in each case
+    including portions thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+    means
+
+    (a) that the initial Contributor has attached the notice described
+        in Exhibit B to the Covered Software; or
+
+    (b) that the Covered Software was made available under the terms of
+        version 1.1 or earlier of the License, but not also under the
+        terms of a Secondary License.
+
+1.6. "Executable Form"
+    means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+    means a work that combines Covered Software with other material, in
+    a separate file or files, that is not Covered Software.
+
+1.8. "License"
+    means this document.
+
+1.9. "Licensable"
+    means having the right to grant, to the maximum extent possible,
+    whether at the time of the initial grant or subsequently, any and
+    all of the rights conveyed by this License.
+
+1.10. "Modifications"
+    means any of the following:
+
+    (a) any file in Source Code Form that results from an addition to,
+        deletion from, or modification of the contents of Covered
+        Software; or
+
+    (b) any new file in Source Code Form that contains any Covered
+        Software.
+
+1.11. "Patent Claims" of a Contributor
+    means any patent claim(s), including without limitation, method,
+    process, and apparatus claims, in any patent Licensable by such
+    Contributor that would be infringed, but for the grant of the
+    License, by the making, using, selling, offering for sale, having
+    made, import, or transfer of either its Contributions or its
+    Contributor Version.
+
+1.12. "Secondary License"
+    means either the GNU General Public License, Version 2.0, the GNU
+    Lesser General Public License, Version 2.1, the GNU Affero General
+    Public License, Version 3.0, or any later versions of those
+    licenses.
+
+1.13. "Source Code Form"
+    means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+    means an individual or a legal entity exercising rights under this
+    License. For legal entities, "You" includes any entity that
+    controls, is controlled by, or is under common control with You. For
+    purposes of this definition, "control" means (a) the power, direct
+    or indirect, to cause the direction or management of such entity,
+    whether by contract or otherwise, or (b) ownership of more than
+    fifty percent (50%) of the outstanding shares or beneficial
+    ownership of such entity.
+
+2. License Grants and Conditions
+--------------------------------
+
+2.1. Grants
+
+Each Contributor hereby grants You a world-wide, royalty-free,
+non-exclusive license:
+
+(a) under intellectual property rights (other than patent or trademark)
+    Licensable by such Contributor to use, reproduce, make available,
+    modify, display, perform, distribute, and otherwise exploit its
+    Contributions, either on an unmodified basis, with Modifications, or
+    as part of a Larger Work; and
+
+(b) under Patent Claims of such Contributor to make, use, sell, offer
+    for sale, have made, import, and otherwise transfer either its
+    Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+The licenses granted in Section 2.1 with respect to any Contribution
+become effective for each Contribution on the date the Contributor first
+distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+The licenses granted in this Section 2 are the only rights granted under
+this License. No additional rights or licenses will be implied from the
+distribution or licensing of Covered Software under this License.
+Notwithstanding Section 2.1(b) above, no patent license is granted by a
+Contributor:
+
+(a) for any code that a Contributor has removed from Covered Software;
+    or
+
+(b) for infringements caused by: (i) Your and any other third party's
+    modifications of Covered Software, or (ii) the combination of its
+    Contributions with other software (except as part of its Contributor
+    Version); or
+
+(c) under Patent Claims infringed by Covered Software in the absence of
+    its Contributions.
+
+This License does not grant any rights in the trademarks, service marks,
+or logos of any Contributor (except as may be necessary to comply with
+the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+No Contributor makes additional grants as a result of Your choice to
+distribute the Covered Software under a subsequent version of this
+License (see Section 10.2) or under the terms of a Secondary License (if
+permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+Each Contributor represents that the Contributor believes its
+Contributions are its original creation(s) or it has sufficient rights
+to grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+This License is not intended to limit any rights You have under
+applicable copyright doctrines of fair use, fair dealing, or other
+equivalents.
+
+2.7. Conditions
+
+Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
+in Section 2.1.
+
+3. Responsibilities
+-------------------
+
+3.1. Distribution of Source Form
+
+All distribution of Covered Software in Source Code Form, including any
+Modifications that You create or to which You contribute, must be under
+the terms of this License. You must inform recipients that the Source
+Code Form of the Covered Software is governed by the terms of this
+License, and how they can obtain a copy of this License. You may not
+attempt to alter or restrict the recipients' rights in the Source Code
+Form.
+
+3.2. Distribution of Executable Form
+
+If You distribute Covered Software in Executable Form then:
+
+(a) such Covered Software must also be made available in Source Code
+    Form, as described in Section 3.1, and You must inform recipients of
+    the Executable Form how they can obtain a copy of such Source Code
+    Form by reasonable means in a timely manner, at a charge no more
+    than the cost of distribution to the recipient; and
+
+(b) You may distribute such Executable Form under the terms of this
+    License, or sublicense it under different terms, provided that the
+    license for the Executable Form does not attempt to limit or alter
+    the recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+You may create and distribute a Larger Work under terms of Your choice,
+provided that You also comply with the requirements of this License for
+the Covered Software. If the Larger Work is a combination of Covered
+Software with a work governed by one or more Secondary Licenses, and the
+Covered Software is not Incompatible With Secondary Licenses, this
+License permits You to additionally distribute such Covered Software
+under the terms of such Secondary License(s), so that the recipient of
+the Larger Work may, at their option, further distribute the Covered
+Software under the terms of either this License or such Secondary
+License(s).
+
+3.4. Notices
+
+You may not remove or alter the substance of any license notices
+(including copyright notices, patent notices, disclaimers of warranty,
+or limitations of liability) contained within the Source Code Form of
+the Covered Software, except that You may alter any license notices to
+the extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+You may choose to offer, and to charge a fee for, warranty, support,
+indemnity or liability obligations to one or more recipients of Covered
+Software. However, You may do so only on Your own behalf, and not on
+behalf of any Contributor. You must make it absolutely clear that any
+such warranty, support, indemnity, or liability obligation is offered by
+You alone, and You hereby agree to indemnify every Contributor for any
+liability incurred by such Contributor as a result of warranty, support,
+indemnity or liability terms You offer. You may include additional
+disclaimers of warranty and limitations of liability specific to any
+jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+---------------------------------------------------
+
+If it is impossible for You to comply with any of the terms of this
+License with respect to some or all of the Covered Software due to
+statute, judicial order, or regulation then You must: (a) comply with
+the terms of this License to the maximum extent possible; and (b)
+describe the limitations and the code they affect. Such description must
+be placed in a text file included with all distributions of the Covered
+Software under this License. Except to the extent prohibited by statute
+or regulation, such description must be sufficiently detailed for a
+recipient of ordinary skill to be able to understand it.
+
+5. Termination
+--------------
+
+5.1. The rights granted under this License will terminate automatically
+if You fail to comply with any of its terms. However, if You become
+compliant, then the rights granted under this License from a particular
+Contributor are reinstated (a) provisionally, unless and until such
+Contributor explicitly and finally terminates Your grants, and (b) on an
+ongoing basis, if such Contributor fails to notify You of the
+non-compliance by some reasonable means prior to 60 days after You have
+come back into compliance. Moreover, Your grants from a particular
+Contributor are reinstated on an ongoing basis if such Contributor
+notifies You of the non-compliance by some reasonable means, this is the
+first time You have received notice of non-compliance with this License
+from such Contributor, and You become compliant prior to 30 days after
+Your receipt of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+infringement claim (excluding declaratory judgment actions,
+counter-claims, and cross-claims) alleging that a Contributor Version
+directly or indirectly infringes any patent, then the rights granted to
+You by any and all Contributors for the Covered Software under Section
+2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all
+end user license agreements (excluding distributors and resellers) which
+have been validly granted by You or Your distributors under this License
+prior to termination shall survive termination.
+
+************************************************************************
+*                                                                      *
+*  6. Disclaimer of Warranty                                           *
+*  -------------------------                                           *
+*                                                                      *
+*  Covered Software is provided under this License on an "as is"       *
+*  basis, without warranty of any kind, either expressed, implied, or  *
+*  statutory, including, without limitation, warranties that the       *
+*  Covered Software is free of defects, merchantable, fit for a        *
+*  particular purpose or non-infringing. The entire risk as to the     *
+*  quality and performance of the Covered Software is with You.        *
+*  Should any Covered Software prove defective in any respect, You     *
+*  (not any Contributor) assume the cost of any necessary servicing,   *
+*  repair, or correction. This disclaimer of warranty constitutes an   *
+*  essential part of this License. No use of any Covered Software is   *
+*  authorized under this License except under this disclaimer.         *
+*                                                                      *
+************************************************************************
+
+************************************************************************
+*                                                                      *
+*  7. Limitation of Liability                                          *
+*  --------------------------                                          *
+*                                                                      *
+*  Under no circumstances and under no legal theory, whether tort      *
+*  (including negligence), contract, or otherwise, shall any           *
+*  Contributor, or anyone who distributes Covered Software as          *
+*  permitted above, be liable to You for any direct, indirect,         *
+*  special, incidental, or consequential damages of any character      *
+*  including, without limitation, damages for lost profits, loss of    *
+*  goodwill, work stoppage, computer failure or malfunction, or any    *
+*  and all other commercial damages or losses, even if such party      *
+*  shall have been informed of the possibility of such damages. This   *
+*  limitation of liability shall not apply to liability for death or   *
+*  personal injury resulting from such party's negligence to the       *
+*  extent applicable law prohibits such limitation. Some               *
+*  jurisdictions do not allow the exclusion or limitation of           *
+*  incidental or consequential damages, so this exclusion and          *
+*  limitation may not apply to You.                                    *
+*                                                                      *
+************************************************************************
+
+8. Litigation
+-------------
+
+Any litigation relating to this License may be brought only in the
+courts of a jurisdiction where the defendant maintains its principal
+place of business and such litigation shall be governed by laws of that
+jurisdiction, without reference to its conflict-of-law provisions.
+Nothing in this Section shall prevent a party's ability to bring
+cross-claims or counter-claims.
+
+9. Miscellaneous
+----------------
+
+This License represents the complete agreement concerning the subject
+matter hereof. If any provision of this License is held to be
+unenforceable, such provision shall be reformed only to the extent
+necessary to make it enforceable. Any law or regulation which provides
+that the language of a contract shall be construed against the drafter
+shall not be used to construe this License against a Contributor.
+
+10. Versions of the License
+---------------------------
+
+10.1. New Versions
+
+Mozilla Foundation is the license steward. Except as provided in Section
+10.3, no one other than the license steward has the right to modify or
+publish new versions of this License. Each version will be given a
+distinguishing version number.
+
+10.2. Effect of New Versions
+
+You may distribute the Covered Software under the terms of the version
+of the License under which You originally received the Covered Software,
+or under the terms of any subsequent version published by the license
+steward.
+
+10.3. Modified Versions
+
+If you create software not governed by this License, and you want to
+create a new license for such software, you may create and use a
+modified version of this License if you rename the license and remove
+any references to the name of the license steward (except to note that
+such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+Licenses
+
+If You choose to distribute Source Code Form that is Incompatible With
+Secondary Licenses under the terms of this version of the License, the
+notice described in Exhibit B of this License must be attached.
+
+Exhibit A - Source Code Form License Notice
+-------------------------------------------
+
+  This Source Code Form is subject to the terms of the Mozilla Public
+  License, v. 2.0. If a copy of the MPL was not distributed with this
+  file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+If it is not possible or desirable to put the notice in a particular
+file, then You may include the notice in a location (such as a LICENSE
+file in a relevant directory) where a recipient would be likely to look
+for such a notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+---------------------------------------------------------
+
+  This Source Code Form is "Incompatible With Secondary Licenses", as
+  defined by the Mozilla Public License, v. 2.0.

README.md

@@ -1,23 +1,87 @@
-# Walk.js (@root/walk)
+# [Walk.js](https://git.rootprojects.org/root/walk.js) (@root/walk)
 
 Walk a directory recursively and handle each entity (files, directories, symlnks, etc).
 
+(a port of Go's [`filepath.Walk`](https://golang.org/pkg/path/filepath/#Walk)
+using Node.js v10+'s `fs.readdir`'s `withFileTypes` and ES 2021)
+
 ```js
 await Walk.walk(pathname, walkFunc);
 
-function walkFunc(err, pathname, dirent) {
-  // ...
+async function walkFunc(err, pathname, dirent) {
+  // err is failure to lstat a file or directory
+  // pathname is relative path, including the file or folder name
+  // dirent = { name, isDirectory(), isFile(), isSymbolicLink(), ... }
+
+  if (err) {
+    return false;
+  }
+  console.log(pathname);
 }
 ```
 
-This is a port of Go's [`filepath.Walk`](https://golang.org/pkg/path/filepath/#Walk)
-for Node.js v10+ (which introduced `fs.readdir` `withFileTypes`) and ES 2021.
+# Table of Contents
 
-# Examples
+- Install
+- Usage
+  - CommonJS
+  - ES Modules
+- API
+  - Walk.walk
+    - walkFunc
+    - Example: filter dotfiles
+  - Walk.create
+    - withFileStats
+    - sort (and filter)
+- [Node walk in <50 Lines of Code](https://therootcompany.com/blog/fs-walk-for-node-js/)
+- License (MPL-2.0)
 
-You can use this with Node v12+ using Vanilla JS or ES2021.
+# Install
 
-## ES 2021 Modules
+```bash
+npm install --save @root/walk
+```
+
+# Usage
+
+You can use this with Node v12+ using Vanilla JS (CommonJS) or ES2021 (ES Modules).
+
+## CommonJS (Vanilla JS / ES5)
+
+```js
+var Walk = require("@root/walk");
+var path = require("path");
+
+Walk.walk("./", walkFunc).then(function () {
+  console.log("Done");
+});
+
+// walkFunc must be async, or return a Promise
+function walkFunc(err, pathname, dirent) {
+  if (err) {
+    // throw an error to stop walking
+    // (or return to ignore and keep going)
+    console.warn("fs stat error for %s: %s", pathname, err.message);
+    return Promise.resolve();
+  }
+
+  // return false to skip a directory
+  // (ex: skipping "dot file" directories)
+  if (dirent.isDirectory() && dirent.name.startsWith(".")) {
+    return Promise.resolve(false);
+  }
+
+  // fs.Dirent is a slimmed-down, faster version of fs.Stats
+  console.log("name:", dirent.name, "in", path.dirname(pathname));
+  // (only one of these will be true)
+  console.log("is file?", dirent.isFile());
+  console.log("is link?", dirent.isSymbolicLink());
+
+  return Promise.resolve();
+}
+```
+
+## ECMAScript 2021 (ES Modules)
 
 `@root/walk` can be used with async/await or Promises.
 
@@ -25,55 +89,28 @@ You can use this with Node v12+ using Vanilla JS or ES2021.
 import { walk } from "@root/walk";
 import path from "path";
 
-await walk("./", async (err, pathname, dirent) => {
-  if (err) {
-    // throw an error to stop walking
-    // (or return to ignore and keep going)
-    console.warn("fs stat error for %s: %s", pathname, err.message);
-    return;
-  }
-
-  // return false to skip a directory
-  // (ex: skipping "dot files")
-  if (dirent.isDirectory() && dirent.name.startsWith(".")) {
-    return false;
-  }
-
-  // fs.Dirent is a slimmed-down, faster version of fs.Stat
-  console.log("name:", dirent.name, "in", path.dirname(pathname));
-  // (only one of these will be true)
-  console.log("is file?", dirent.isFile());
-  console.log("is link?", dirent.isSymbolicLink());
-});
-
-console.log("Done");
-```
-
-## Vanilla JS (ES5)
-
-```js
-var Walk = require("@root/walk");
-var path = require("path");
-
-Walk.walk("./", function walkFunc(err, pathname, dirent) {
+const walkFunc = async (err, pathname, dirent) => {
   if (err) {
     throw err;
   }
 
   if (dirent.isDirectory() && dirent.name.startsWith(".")) {
-    return Promise.resolve(false);
+    return false;
   }
-  console.log("name:", dirent.name, "in", path.dirname(pathname));
 
-  return Promise.resolve();
-}).then(function () {
-  console.log("Done");
-});
+  console.log("name:", dirent.name, "in", path.dirname(pathname));
+};
+
+await walk("./", walkFunc);
+
+console.log("Done");
 ```
 
 # API Documentation
 
-`Walk.walk` walks `pathname` (inclusive) and calls `walkFunc` for each file system entry.
+## Walk.walk(pathname, walkFunc)
+
+`Walk.walk` walks `pathname` (inclusive) and calls `walkFunc` for each file system entity.
 
 It can be used with Promises:
 
@@ -88,21 +125,18 @@ await Walk.walk(pathname, asyncWalker);
 ```
 
 The behavior should exactly match Go's
-[`filepath.Walk`](https://golang.org/pkg/path/filepath/#Walk) with 3 exceptions:
+[`filepath.Walk`](https://golang.org/pkg/path/filepath/#Walk) with a few exceptions:
 
 - uses JavaScript Promises/async/await
-- receives `dirent` rather than `lstat` (for performance)
+- receives `dirent` rather than `lstat` (for performance, see `withFileStats`)
+- optional parameters to change stat behavior and sort order
 
-<!-- TODO
-- can be created with `options` to change default behaviors
--->
-
-## walkFunc
+### walkFunc
 
 Handles each directory entry
 
 ```js
-function walker(err, pathname, dirent) {
+async function walkFunc(err, pathname, dirent) {
   // `err` is a file system stat error
   // `pathname` is the full pathname, including the file name
   // `dirent` is an fs.Dirent with a `name`, `isDirectory`, `isFile`, etc
@@ -110,11 +144,82 @@ function walker(err, pathname, dirent) {
 }
 ```
 
-<!-- TODO
-## create(options)
+## Walk.create(options)
 
 Create a custom walker with these options:
 
-- `withFileTypes: false` walkFunc will receive String[] instead of fs.Dirent[]
-- `sort: sortFunc`
--->
+- `withFileStats: true` walkFunc will receive fs.Stats[] from fs.lstat instead of fs.Dirent[]
+- `sort: (entities) => entities.sort()` sort and/or filter entities before walking them
+
+```js
+const walk = Walk.create({
+  withFileStats: true,
+  sort: (entities) => entities.sort()),
+});
+```
+
+## withFileStats
+
+By default `walk` will use `fs.readdir(pathname, { withFileTypes: true })` which returns `fs.Dirent[]`,
+which only has name and file type info, but is much faster when you don't need the complete `fs.Stats`.
+
+Enable `withFileStats` to use get full `fs.Stats`. This will use `fs.readdir(pathname)` (returning `String[]`)
+and then call `fs.lstat(pathname)` - including `mtime`, `birthtime`, `uid`, etc - right after.
+
+```js
+const walk = Walk.create({
+  withFileStats: true,
+});
+
+walk(".", async function (err, pathname, stat) {
+  console.log(stat.name, stat.uid, stat.birthtime, stat.isDirectory());
+});
+```
+
+## sort (and filter)
+
+Sometimes you want to give priority to walking certain directories first.
+
+The `sort` option allows you to specify a funciton that modifies the `fs.Dirent[]` entities (default) or `String[]` filenames (`withFileStats: true`).
+
+Since you must return the sorted array, you can also filter here if you'd prefer.
+
+```js
+const byNameWithoutDotFiles = (entities) => {
+  // sort by name
+  // filter dot files
+  return entities
+    .sort((a, b) => {
+      if (a.name > b.name) {
+        return 1;
+      }
+      if (a.name < b.name) {
+        return -1;
+      }
+      return 0;
+    })
+    .filter((ent) => !ent.name.startsWith("."));
+};
+
+const walk = Walk.create({ sort: byNameWithoutDotFiles });
+
+walk(".", async function (err, pathname, stat) {
+  // each directories contents will be listed alphabetically
+  console.log(pathname);
+});
+```
+
+Note: this gets the result of `fs.readdir()`. If `withFileStats` is `true` you will get a `String[]` of filenames - because this hapens BEFORE `fs.lstat()` is called - otherwise you will get `fs.Dirent[]`.
+
+# node walk in 50 lines of code
+
+If you're like me and you hate dependencies,
+here's the bare minimum node fs walk function:
+
+See [snippet.js](/snippet.js) or <https://therootcompany.com/blog/fs-walk-for-node-js/>.
+
+# License
+
+The main module, as published to NPM, is licensed the MPL-2.0.
+
+The ~50 line snippet is licensed CC0-1.0 (Public Domain).

bin/walk.js

@@ -1,28 +1,43 @@
-import Walk from "../index.js";
-import path from "path";
+"use strict";
+
+var path = require("path");
+var Walk = require("../index.js");
+
+var walk = Walk.walk;
+var alt = process.argv[2];
+
+if (alt) {
+  walk = Walk.create({
+    sort: function (ents) {
+      return ents.filter(function (ent) {
+        return !ent.name.startsWith(".");
+      });
+    },
+  });
+}
 
 var rootpath = process.argv[2] || ".";
 
-Walk.walk(rootpath, async function (err, pathname, dirent) {
+walk(rootpath, async function (err, pathname, dirent) {
   if (err) {
     throw err;
   }
 
-  if (dirent.name.startsWith(".")) {
-    return false;
+  if (!alt) {
+    if (dirent.name.startsWith(".")) {
+      return false;
+    }
   }
 
-  var entType;
+  var entType = "?";
   if (dirent.isDirectory()) {
-    entType = " dir";
+    entType = "d";
   } else if (dirent.isFile()) {
-    entType = "file";
+    entType = "f";
   } else if (dirent.isSymbolicLink()) {
-    entType = "link";
-  } else {
-    entType = "----";
+    entType = "@";
   }
-  console.info("[%s] %s", entType, path.dirname(path.resolve(pathname)), dirent.name);
+  console.info("%s %s", entType, path.dirname(path.resolve(pathname)), dirent.name);
 }).catch(function (err) {
   console.error(err.stack);
 });

create.js

@@ -1,110 +1,73 @@
+"use strict";
+
+const fs = require("fs").promises;
+const Walk = require("./walk.js");
+const path = require("path");
+const _withFileTypes = { withFileTypes: true };
+const _noopts = {};
+const _pass = (err) => err;
+
 // a port of Go's filepath.Walk
-
-import { promises as fs } from "fs";
-import { skipDir } from "./walk.js";
-import path from "path";
-
-var Walk = {};
-var _withFileTypes = { withFileTypes: true };
-var _noopts = {};
-
-function pass(err) {
-  return err;
-}
-
-function skipOrThrow(err) {
-  if (!(err instanceof Error)) {
-    // go
-    return false;
-  }
-  if (false === err || skipDir === err) {
-    // skip
-    return true;
-  }
-  // throw
-  throw err;
-}
-
-Walk.skipDir = skipDir;
-
 Walk.create = function (opts) {
-  async function _walk(root, walker) {
-    if (!opts) {
-      opts = _noopts;
+  if (!opts) {
+    opts = _noopts;
+  }
+
+  // a port of Go's filepath.Walk
+  const _walk = async (pathname, walkFunc, _dirent) => {
+    let err;
+
+    // special case of the very first run
+    if (!_dirent) {
+      _dirent = pathname;
     }
 
-    // Special case of the very first item, root
-    var err;
-    var stat = await fs.lstat(root).catch(function (e) {
-      err = e;
-      return null;
-    });
-    if (stat) {
-      stat.name = path.basename(path.resolve(root));
+    // the first run, or if false === withFileTypes
+    if ("string" === typeof _dirent) {
+      let _name = path.basename(path.resolve(pathname));
+      _dirent = await fs.lstat(pathname).catch(_pass);
+      if (_dirent instanceof Error) {
+        err = _dirent;
+      } else {
+        _dirent.name = _name;
+      }
     }
 
-    /* similar to function in main walk loop */
-    var uerr = await walker(err, root, stat).then(pass).catch(pass);
-    if (skipOrThrow(uerr) || err) {
+    // run the user-supplied function and either skip, bail, or continue
+    err = await walkFunc(err, pathname, _dirent).catch(_pass);
+    if (false === err || Walk.skipDir === err) {
+      return;
+    }
+    if (err instanceof Error) {
+      throw err;
+    }
+
+    // "walk does not follow symbolic links"
+    if (!_dirent || !_dirent.isDirectory()) {
       return;
     }
 
-    if (false === opts.withFileTypes) {
-      stat = stat.name;
+    // lightweight dirents or full lstat
+    let _readdirOpts;
+    if (!opts.withFileStats) {
+      _readdirOpts = _withFileTypes;
+    }
+
+    // TODO check if the error is "not a directory"
+    // (and thus allow false === opts.withFileTypes)
+    let result = await fs.readdir(pathname, _readdirOpts).catch(_pass);
+    if (result instanceof Error) {
+      return walkFunc(result, pathname, _dirent);
     }
     if (opts.sort) {
-      stat = (opts.sort([stat]) || [])[0];
+      result = opts.sort(result);
     }
-
-    if (stat && stat.isDirectory()) {
-      return _walkHelper(root, stat, walker, opts);
+    for (let entity of result) {
+      await _walk(path.join(pathname, entity.name || entity), walkFunc, entity);
     }
-    /* end */
-
-    async function _walkHelper(root, prevEnt, walker, opts) {
-      var err;
-      var _readdirOpts;
-      if (false !== opts.withFileTypes) {
-        _readdirOpts = _withFileTypes;
-      }
-      var dirents = await fs.readdir(root, _readdirOpts).catch(function (e) {
-        err = e;
-      });
-      if (err) {
-        return walker(err, root, prevEnt);
-      }
-      if (opts.sort) {
-        dirents = opts.sort(dirents);
-      }
-
-      var dirent;
-      var pathname;
-      for (dirent of dirents) {
-        if ("string" === typeof dirent) {
-          pathname = path.join(root, dirent);
-          dirent = await fs.lstat(path.join(root)).catch(function (e) {
-            err = e;
-          });
-        } else {
-          pathname = path.join(root, dirent.name);
-        }
-
-        /* main inner loop */
-        err = await walker(err, pathname, dirent).then(pass).catch(pass);
-        if (skipOrThrow(err)) {
-          continue;
-        }
-
-        // "walk does not follow symbolic links"
-        if (dirent.isDirectory()) {
-          await _walkHelper(path.join(root, dirent.name), dirent, walker, opts);
-        }
-        /* end */
-      }
-    }
-  }
+  };
 
   return _walk;
 };
 
-export default Walk;
+module.exports = Walk;

index.js

@@ -1,3 +1,4 @@
-import Walk from "./walk.js";
+"use strict";
 
-export default Walk;
+module.exports = require("./walk.js");
+module.exports.create = require("./create.js").create;

package-lock.json

@@ -1,5 +1,5 @@
 {
   "name": "@root/walk",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "lockfileVersion": 1
 }

package.json

@@ -1,14 +1,15 @@
 {
   "name": "@root/walk",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "description": "fs.walk for node (as a port of Go's filepath.Walk)",
   "homepage": "https://git.rootprojects.org/root/walk.js",
   "main": "index.js",
-  "type": "module",
   "files": [
-    "walk.js"
+    "walk.js",
+    "create.js"
   ],
   "scripts": {
+    "prettier": "npx prettier --write '**/*.{md,js,mjs,cjs}'",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "repository": {

snippet.js

@@ -0,0 +1,77 @@
+/**
+ * @license
+ * walk.js - fs.walk for node.js (a port of Go's filepath.Walk)
+ *
+ * Written in 2020 by AJ ONeal <coolaj86@gmail.com>
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along with
+ * this software. If not, see <https://creativecommons.org/publicdomain/zero/1.0/>.
+ */
+
+"use strict";
+
+async function walk(pathname, walkFunc, dirent) {
+  const fs = require("fs").promises;
+  const path = require("path");
+  const _pass = (err) => err;
+
+  let err;
+
+  // special case: walk the very first file or folder
+  if (!dirent) {
+    let filename = path.basename(path.resolve(pathname));
+    dirent = await fs.lstat(pathname).catch(_pass);
+    if (dirent instanceof Error) {
+      err = dirent;
+    } else {
+      dirent.name = filename;
+    }
+  }
+
+  // run the user-supplied function and either skip, bail, or continue
+  err = await walkFunc(err, pathname, dirent).catch(_pass);
+  if (false === err) {
+    // walkFunc can return false to skip
+    return;
+  }
+  if (err instanceof Error) {
+    // if walkFunc throws, we throw
+    throw err;
+  }
+
+  // "walk does not follow symbolic links"
+  // (doing so could cause infinite loops)
+  if (!dirent.isDirectory()) {
+    return;
+  }
+  let result = await fs.readdir(pathname, { withFileTypes: true }).catch(_pass);
+  if (result instanceof Error) {
+    // notify on directory read error
+    return walkFunc(result, pathname, dirent);
+  }
+  for (let entity of result) {
+    await walk(path.join(pathname, entity.name), walkFunc, entity);
+  }
+}
+
+// Example Usage:
+const path = require("path");
+walk("./", function (err, pathname, dirent) {
+  if (dirent.name.startsWith(".")) {
+    return Promise.resolve(false);
+  }
+
+  var typ = "-";
+  if (dirent.isFile()) {
+    typ = "f";
+  } else if (dirent.isDirectory()) {
+    typ = "d";
+  } else if (dirent.isSymbolicLink()) {
+    typ = "@";
+  }
+  console.info(typ, path.resolve(pathname));
+  return Promise.resolve(true);
+});

walk.js

@@ -1,18 +1,20 @@
-import { promises as fs } from "fs";
-import path from "path";
+"use strict";
+
+const fs = require("fs").promises;
+const path = require("path");
 
-const _withFileTypes = { withFileTypes: true };
 const skipDir = new Error("skip this directory");
+const _withFileTypes = { withFileTypes: true };
 const pass = (err) => err;
 
 // a port of Go's filepath.Walk
-const walk = async (root, walkFunc, _dirent) => {
+const walk = async (pathname, walkFunc, _dirent) => {
   let err;
 
   // special case of the very first run
   if (!_dirent) {
-    let _name = path.basename(path.resolve(root));
-    _dirent = await fs.lstat(root).catch(pass);
+    let _name = path.basename(path.resolve(pathname));
+    _dirent = await fs.lstat(pathname).catch(pass);
     if (_dirent instanceof Error) {
       err = _dirent;
     } else {
@@ -21,7 +23,7 @@ const walk = async (root, walkFunc, _dirent) => {
   }
 
   // run the user-supplied function and either skip, bail, or continue
-  err = await walkFunc(err, root, _dirent).catch(pass);
+  err = await walkFunc(err, pathname, _dirent).catch(pass);
   if (false === err || skipDir === err) {
     return;
   }
@@ -33,16 +35,16 @@ const walk = async (root, walkFunc, _dirent) => {
   if (!_dirent.isDirectory()) {
     return;
   }
-  let result = await fs.readdir(root, _withFileTypes).catch(pass);
+  let result = await fs.readdir(pathname, _withFileTypes).catch(pass);
   if (result instanceof Error) {
-    return walkFunc(result, root, _dirent);
+    return walkFunc(result, pathname, _dirent);
   }
   for (let dirent of result) {
-    await walk(path.join(root, dirent.name), walkFunc, dirent);
+    await walk(path.join(pathname, dirent.name), walkFunc, dirent);
   }
 };
 
-export default {
+module.exports = {
   walk,
   skipDir,
 };