Don't override fs module, export constants as object

[ikokostya]

This PR removes override of fs and constants core Node.js modules. Instead all functions and constants should be imported explicitly:

const {flock, constants} = require('fs-ext');
// or
const fsExt = require('fs-ext');
// fsExt.flock
// fsExt.constants

In C++ binding all constants are placed to constants object instead of target object, e.g. on my machine:

> require('./build/Release/fs-ext')
{ constants:
   { SEEK_SET: 0,
     SEEK_CUR: 1,
     SEEK_END: 2,
     LOCK_SH: 1,
     LOCK_EX: 2,
     LOCK_NB: 4,
     LOCK_UN: 8,
     F_GETFD: 1,
     F_SETFD: 2,
     FD_CLOEXEC: 1,
     F_RDLCK: 0,
     F_WRLCK: 1,
     F_UNLCK: 2,
     F_SETLK: 6,
     F_GETLK: 5,
     F_SETLKW: 7 },
  seek: [Function],
  fcntl: [Function],
  flock: [Function],
  statVFS: [Function] }

This helps to export constants on JavaScript side without pattern matching:

node-fs-ext/fs-ext.js

Line 142 in 42b8713

if (/^[A-Z_]+$/.test(key) && !constants.hasOwnProperty(key)) {

Other changes

• Use fsExt module in tests instead binding directly.
• Update examples in README.md to use modern JavaScript (destructuring, arrow functions), because minimum supported version is Node.js 8.

Please note that it's breaking change. Therefore, major version should be updated.

Fixes #89
Fixes #81

[ikokostya]

I don't touch this file. I think it was synchronized with package.json during execution of npm install command.

[baudehlo]

Looks good, but needs a major version bump (package.json), and something in the README about the change.

[ikokostya]

Looks good, but needs a major version bump (package.json)

OK. Usually maintainer updates version of the package before publishing it to npm repository:

npm version major
npm pubish

But I can update version manually in package.json. It's not a problem.

and something in the README about the change.

I think that best place for this is new CHANGELOG.md file.

[ikokostya]

@baudehlo Done.

[baudehlo]

Thanks - I can't keep up with the way npm keeps changing how things are done these days - back when I wrote this you had to edit package.json manually.

…

On Thu, Nov 7, 2019 at 2:16 PM ikokostya ***@***.***> wrote: @baudehlo <https://github.com/baudehlo> Done. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#90?email_source=notifications&email_token=AAFBWY4W3ST2WHLZDEFSLGTQSRSRPA5CNFSM4JHT7T2KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEDNP7CY#issuecomment-551223179>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAFBWYZGA4UWYUYKK5U4FC3QSRSRPANCNFSM4JHT7T2A> .

[baudehlo]

$ npm publish
npm notice 
npm notice 📦  fs-ext@2.0.0
npm notice === Tarball Contents === 
npm notice 986B   package.json                 
npm notice 1.6kB  .eslintrc                    
npm notice 404B   .travis.yml                  
npm notice 242B   appveyor.yml                 
npm notice 219B   binding.gyp                  
npm notice 1.3kB  example.js                   
npm notice 17.1kB fs-ext.cc                    
npm notice 3.4kB  fs-ext.js                    
npm notice 1.0kB  LICENSE.txt                  
npm notice 3.2kB  README.md                    
npm notice 310B   run_tests.js                 
npm notice 316B   wscript                      
npm notice 7.7kB  tests/test-fs-fcntl.js       
npm notice 5.7kB  tests/test-fs-flock_stress.js
npm notice 10.7kB tests/test-fs-flock.js       
npm notice 9.1kB  tests/test-fs-seek_stress.js 
npm notice 14.8kB tests/test-fs-seek.js        
npm notice 267B   tests/test-fs-statvfs.js     
npm notice === Tarball Details === 
npm notice name:          fs-ext                                  
npm notice version:       2.0.0                                   
npm notice package size:  14.6 kB                                 
npm notice unpacked size: 78.4 kB                                 
npm notice shasum:        e58168fcc37506a9358e0928f4aae60912af7caa
npm notice integrity:     sha512-aK8NlpSO5LUdS[...]u1aGS8deJwzBQ==
npm notice total files:   18                                      
npm notice 
+ fs-ext@2.0.0

[baudehlo]

Thanks for this! Real nice change.

[ikokostya]

Thanks for review!

[baudehlo]

I've also added you as a collaborator to the project.

…

On Thu, Nov 7, 2019 at 4:27 PM ikokostya ***@***.***> wrote: Thanks for review! — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <#90?email_source=notifications&email_token=AAFBWYZOSPBROXDXFBKBAJ3QSSB4DA5CNFSM4JHT7T2KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEDN36XY#issuecomment-551272287>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAFBWY4S3MCK2ILGF2MQ3W3QSSB4DANCNFSM4JHT7T2A> .