Don't override fs module, export constants as object (#90)

* Don't override fs module, export constants as object

Fixes #89
Fixes #81

* Desctibe breaking changes in README.md

* Bump major version in package.json

README.md

@@ -7,15 +7,30 @@ fs-ext
 
 Extras not included in Node's fs module.
 
-**Note**: From v1.0.0 onwards, fs.utime and fs.utimeSync have been removed.
-Use fs.utimes and fs.utimesSync instead.
+**Note**:
+
+* From `v2.0.0` onwards, module doesn't override `fs` and `constants` Node.js core modules. Instead
+  import functions and constants directly:
+
+  ```js
+  const {flock, constants} = require('fs-ext');
+  // or
+  const fsExt = require('fs-ext');
+  // fsExt.flock
+  // fsExt.constants
+  ```
+
+* From `v1.0.0` onwards, fs.utime and fs.utimeSync have been removed.
+  Use fs.utimes and fs.utimesSync instead.
 
 Installation
 ------------
 
 Install via npm:
 
-    npm install fs-ext
+```sh
+npm install fs-ext
+```
 
 Usage
 -----
@@ -24,22 +39,24 @@ fs-ext imports all of the methods from the core 'fs' module, so you don't
 need two objects.
 
 ```js
-var fs = require('fs-ext');
-var fd = fs.openSync('foo.txt', 'r');
-fs.flock(fd, 'ex', function (err) {
+const fs = require('fs');
+const {flock} = require('fs-ext');
+
+const fd = fs.openSync('foo.txt', 'r');
+flock(fd, 'ex', (err) => {
     if (err) {
-        return console.log("Couldn't lock file");
+        return console.error("Couldn't lock file");
     }
     // file is locked
-})
+});
 ```
 
 For an advanced example checkout `example.js`.
 
 API
 ---
 
-### fs.flock(fd, flags, [callback])
+### flock(fd, flags, [callback])
 
 Asynchronous flock(2). No arguments other than a possible error are passed to
 the callback. Flags can be 'sh', 'ex', 'shnb', 'exnb', 'un' and correspond
@@ -50,11 +67,11 @@ instead: that does work over NFS, given a sufficiently recent version of Linux
 and a server which supports locking.
 
 
-### fs.flockSync(fd, flags)
+### flockSync(fd, flags)
 
 Synchronous flock(2). Throws an exception on error.
 
-### fs.fcntl(fd, cmd, [arg], [callback])
+### fcntl(fd, cmd, [arg], [callback])
 
 Asynchronous fcntl(2).
 
@@ -74,29 +91,31 @@ and also F_RDLCK, F_WRLCK and F_UNLCK for use with F_SETLK (etc).
 File locking can be used like so:
 
 ```js
-fs.fcntl(fd, 'setlkw', constants.F_WRLCK, function (err, result) {
-    if (result != null) {
-        //Lock succeeded
+const {fnctl, constants} = require('fs-ext');
+
+fcntl(fd, 'setlkw', constants.F_WRLCK, (err) => {
+    if (!err) {
+        // Lock succeeded
     }
 });
 ```
 
-### fs.fcntlSync(fd, flags)
+### fcntlSync(fd, flags)
 
 Synchronous fcntl(2). Throws an exception on error.
 
-### fs.seek(fd, offset, whence, [callback])
+### seek(fd, offset, whence, [callback])
 
-Asynchronous lseek(2).  
+Asynchronous lseek(2).
 
 callback will be given two arguments (err, currFilePos).
 
-whence can be 0 (SEEK_SET) to set the new position in bytes to offset, 
-1 (SEEK_CUR) to set the new position to the current position plus offset 
-bytes (can be negative), or 2 (SEEK_END) to set to the end of the file 
+whence can be 0 (SEEK_SET) to set the new position in bytes to offset,
+1 (SEEK_CUR) to set the new position to the current position plus offset
+bytes (can be negative), or 2 (SEEK_END) to set to the end of the file
 plus offset bytes (usually negative or zero to seek to the end of the file).
 
-### fs.seekSync(fd, offset, whence)
+### seekSync(fd, offset, whence)
 
 Synchronous lseek(2). Throws an exception on error.  Returns current
 file position.

example.js

@@ -1,6 +1,7 @@
 "use strict";
 
-var fs = require('./');
+var fs = require('fs');
+var {flock} = require('./');
 
 /**
  * Function that locks the current file
@@ -17,7 +18,7 @@ function getCurrentFileSize(counter, timeout, cb) {
 
   console.log("Trying to aquire lock for the %s time", counter);
 
-  fs.flock(fd, 'exnb', function(err) {
+  flock(fd, 'exnb', function(err) {
     if (err) {
       return console.log("Couldn't lock file", counter);
     }
@@ -26,7 +27,7 @@ function getCurrentFileSize(counter, timeout, cb) {
 
     // unlock after `timeout`
     setTimeout(function() {
-      fs.flock(fd, 'un', function(err) {
+      flock(fd, 'un', function(err) {
         if (err) {
           return console.log("Couldn't unlock file", counter);
         }

fs-ext.cc

@@ -240,21 +240,21 @@ static void EIO_Seek(uv_work_t *req) {
 #ifndef _WIN32
 static void EIO_Fcntl(uv_work_t *req) {
   store_data_t* data = static_cast<store_data_t *>(req->data);
-  
+
   struct flock lk;
   lk.l_start = 0;
   lk.l_len = 0;
   lk.l_type = 0;
   lk.l_whence = 0;
   lk.l_pid = 0;
-  
+
   int result = -1;
   if (data->oper == F_GETLK || data->oper == F_SETLK || data->oper == F_SETLKW) {
 	if (data->oper == F_SETLK || data->oper == F_SETLKW) {
 		lk.l_whence = SEEK_SET;
 		lk.l_type   = data->arg;
 	}
-	data->result = result = fcntl(data->fd, data->oper, &lk); 
+	data->result = result = fcntl(data->fd, data->oper, &lk);
   } else {
   	data->result = result = fcntl(data->fd, data->oper, data->arg);
   }
@@ -316,7 +316,7 @@ static int _win32_flock(int fd, int oper) {
       return -1;
   }
   if (i == -1) {
-    if (GetLastError() == ERROR_LOCK_VIOLATION) 
+    if (GetLastError() == ERROR_LOCK_VIOLATION)
       errno = EWOULDBLOCK;
     else
       errno = EINVAL;
@@ -525,69 +525,74 @@ NAN_MODULE_INIT(init)
   _set_invalid_parameter_handler(uv__crt_invalid_parameter_handler);
 #endif
 
+  v8::Local<v8::Object> constants = Nan::New<v8::Object>();
+
 #ifdef SEEK_SET
-  NODE_DEFINE_CONSTANT(target, SEEK_SET);
+  NODE_DEFINE_CONSTANT(constants, SEEK_SET);
 #endif
 
 #ifdef SEEK_CUR
-  NODE_DEFINE_CONSTANT(target, SEEK_CUR);
+  NODE_DEFINE_CONSTANT(constants, SEEK_CUR);
 #endif
 
 #ifdef SEEK_END
-  NODE_DEFINE_CONSTANT(target, SEEK_END);
+  NODE_DEFINE_CONSTANT(constants, SEEK_END);
 #endif
 
 #ifdef LOCK_SH
-  NODE_DEFINE_CONSTANT(target, LOCK_SH);
+  NODE_DEFINE_CONSTANT(constants, LOCK_SH);
 #endif
 
 #ifdef LOCK_EX
-  NODE_DEFINE_CONSTANT(target, LOCK_EX);
+  NODE_DEFINE_CONSTANT(constants, LOCK_EX);
 #endif
 
 #ifdef LOCK_NB
-  NODE_DEFINE_CONSTANT(target, LOCK_NB);
+  NODE_DEFINE_CONSTANT(constants, LOCK_NB);
 #endif
 
 #ifdef LOCK_UN
-  NODE_DEFINE_CONSTANT(target, LOCK_UN);
+  NODE_DEFINE_CONSTANT(constants, LOCK_UN);
 #endif
 
 #ifdef F_GETFD
-  NODE_DEFINE_CONSTANT(target, F_GETFD);
+  NODE_DEFINE_CONSTANT(constants, F_GETFD);
 #endif
 
 #ifdef F_SETFD
-  NODE_DEFINE_CONSTANT(target, F_SETFD);
+  NODE_DEFINE_CONSTANT(constants, F_SETFD);
 #endif
 
 #ifdef FD_CLOEXEC
-  NODE_DEFINE_CONSTANT(target, FD_CLOEXEC);
+  NODE_DEFINE_CONSTANT(constants, FD_CLOEXEC);
 #endif
 
 #ifdef F_RDLCK
-  NODE_DEFINE_CONSTANT(target, F_RDLCK);
+  NODE_DEFINE_CONSTANT(constants, F_RDLCK);
 #endif
 
 #ifdef F_WRLCK
-  NODE_DEFINE_CONSTANT(target, F_WRLCK);
+  NODE_DEFINE_CONSTANT(constants, F_WRLCK);
 #endif
 
 #ifdef F_UNLCK
-  NODE_DEFINE_CONSTANT(target, F_UNLCK);
+  NODE_DEFINE_CONSTANT(constants, F_UNLCK);
 #endif
 
 #ifdef F_SETLK
-  NODE_DEFINE_CONSTANT(target, F_SETLK);
+  NODE_DEFINE_CONSTANT(constants, F_SETLK);
 #endif
 
 #ifdef F_GETLK
-  NODE_DEFINE_CONSTANT(target, F_GETLK);
+  NODE_DEFINE_CONSTANT(constants, F_GETLK);
 #endif
 
 #ifdef F_SETLKW
-  NODE_DEFINE_CONSTANT(target, F_SETLKW);
+  NODE_DEFINE_CONSTANT(constants, F_SETLKW);
 #endif
+
+  Nan::Set(target, Nan::New("constants").ToLocalChecked(), constants);
+
   Export(target, "seek", Seek);
 #ifndef _WIN32
   Export(target, "fcntl", Fcntl);

fs-ext.js

@@ -20,8 +20,6 @@
 "use strict";
 
 var binding = require('./build/Release/fs-ext');
-var fs = require('fs');
-var constants = require('constants');
 
 // Used by flock
 function stringToFlockFlags(flag) {
@@ -31,19 +29,19 @@ function stringToFlockFlags(flag) {
   }
   switch (flag) {
     case 'sh':
-      return binding.LOCK_SH;
+      return binding.constants.LOCK_SH;
 
     case 'ex':
-      return binding.LOCK_EX;
+      return binding.constants.LOCK_EX;
 
     case 'shnb':
-      return binding.LOCK_SH | binding.LOCK_NB;
+      return binding.constants.LOCK_SH | binding.constants.LOCK_NB;
 
     case 'exnb':
-      return binding.LOCK_EX | binding.LOCK_NB;
+      return binding.constants.LOCK_EX | binding.constants.LOCK_NB;
 
     case 'un':
-      return binding.LOCK_UN;
+      return binding.constants.LOCK_UN;
 
     default:
       throw new Error('Unknown flock flag: ' + flag);
@@ -58,19 +56,19 @@ function stringToFcntlFlags(flag) {
 
   switch (flag) {
     case 'getfd':
-      return binding.F_GETFD;
+      return binding.constants.F_GETFD;
 
     case 'setfd':
-      return binding.F_SETFD;
+      return binding.constants.F_SETFD;
 
     case 'setlk':
-      return binding.F_SETLK;
+      return binding.constants.F_SETLK;
 
     case 'setlkw':
-      return binding.F_SETLKW;
+      return binding.constants.F_SETLKW;
 
     case 'getlk':
-      return binding.F_GETLK;
+      return binding.constants.F_GETLK;
 
     default:
       throw new Error('Unknown fcntl flag: ' + flag);
@@ -130,18 +128,4 @@ exports.statVFS = function(path, callback) {
   return binding.statVFS(path, callback);
 };
 
-// populate with fs functions from there
-var key;
-for (key in fs) {
-  exports[key] = fs[key];
-}
-
-// put constants into constants module (don't like doing this but...)
-if (!Object.isExtensible || Object.isExtensible(constants)) {
-  for (key in binding) {
-    if (/^[A-Z_]+$/.test(key) && !constants.hasOwnProperty(key)) {
-      constants[key] = binding[key];
-    }
-  }
-}
-
+exports.constants = binding.constants;

package.json

@@ -8,7 +8,7 @@
     "flock",
     "seek"
   ],
-  "version": "1.3.0",
+  "version": "2.0.0",
   "homepage": "https://github.com/baudehlo/node-fs-ext/",
   "repository": {
     "type": "git",