Add support for node 4.x.x

[wmonk]

Now that node 4.0.0 has been released as the stable version, it would be great to add support for this version.

[blond]

👍

[pezza3434]

👍

[tschaub]

I've started work on this. If anybody else wants to take it, feel free - I may not have a chance to finish it for the next week. It looks like this may require more significantly patching the built-in fs module and providing an implementation of binding.FSReqWrap.

[sleexyz]

👍

[mlegenhausen]

+1

[kdelmonte]

+1

[ylallemant]

+1

[luscus]

+1

[ariporad]

+1, this is a really useful tool, and I'd love to be able to use it.

[sveisvei]

+1

[ariporad]

@tschaub: Actually, how would I go about bringing support for this to node? I dislike +1ing without at least offering some help, and I'd really like to see this happen, so what can I do?

[catdad]

@ariporad I started looking at this as well. The lib is laid out to mock each major version of Node separately. I added 4.x to the list to use the mock for 3.0.0, and all of the tests passed, so I am not actually sure what is wrong. It seems that, at least for most common things, the lib should already work. I will run my suite of tests tomorrow against this (I have a couple of projects that use this lib for testing) just to confirm.

Perhaps @tschaub can tell us a bit more about he problems he is aware of. I'd also like to help in getting this working.

[tschaub]

@catdad - if we want a quick win, we could use the monkey patched fs.js for version 3 when running Node 4. For that matter, the fs.js from version 0.8 could be used. This would only be a problem for people that are using features introduced between these versions.

I'm hoping to find a different way to swap out the fs binding in a way that would be more future-proof. But I'd also consider a pull-request that took the quick-win approach for v4 (bonus points if you can document any limitations or caveats associated with using fs.js from v3).

[voxpelli]

As io.js v3 was more or less a release candidate for node.js v4 there shouldn't really be any differences and the CHANGELOG points out no changes in regards to the fs-module between the two: https://github.com/nodejs/node/blob/master/CHANGELOG.md#2015-09-08-version-400-stable-rvagg

The only fs-module change since io.js 3.3.0 that's in the CHANGELOG are two small changes in 4.1.0: https://github.com/nodejs/node/blob/master/CHANGELOG.md#2015-09-17-version-410-stable-fishrock123

I'm in favor of reusing the fs.js from version 3.

I think I'm actually in favor of always using the newest fs.js mock when a specific one can't be find for the current version of node – and just warn about the fact that some newer additions or tweaks might not fully match. That way we can discover shortcomings in newer versions and report those rather than having issues like this one that's about getting mock-fs to at all work.

[catdad]

Looking at the links @voxpelli provided, and a bit of extra research, I also believe there is no differences to be concerned about between 3.x and 4.x (as long as the 3.x implementation here is good, of course).

I ran tests for all my projects using my updated mock-fs against 4.1.2, and all of my tests passed. I don't know about most people, but my projects tend to just use the read and write streams to read and write from the filesystem, which don't really change. It's not worth it to me to hold off on being able to test those simple cases because there might be an obscure change in a new release. If this was my lib, I'd go with @voxpelli 's approach of letting users report specific issues to new implementation of Node. This is actually the first module I have run across that does a hard coded version check.

[mlegenhausen]

Would it be possible to mark the support for 4.x.x as experimental. I haven't encountered any bugs yet and it would be great to use the npm repository instead of a git branch.

[danez]

Could we get a new release now please :)

[mlegenhausen]

+1