Drop Node 4 support

[devoto13]

Node 4 has reached end-of-life on 30th of April. There are libraries out there, which have already dropped support for it to benefit from new ES feature available with newer versions.

Opening this issue to discuss how Karma can drop Node 4 support. This will probably require a major version bump as it will break everybody, who is stuck with Node 4.

Benefits of dropping Node 4 support:

• class is available without strict mode
• support for default parameter values in functions
• support for rest function parameters (which is better alternative for arguments and will allow to move remaining functions to arrow functions)
• new methods on Array, Promise and other built-in objects
• detailed in the compat-table

So, what does it take to drop support for Node 4?

[lusarz]

I definetely agree with @devoto13.

I think it may be enough to prepare pull request which remove these lines:

karma/appveyor.yml

Line 5 in 80cf39c

- nodejs_version: "4"

karma/.travis.yml

Line 4 in 3add635

- 4

[johnjbarton]

I guess we should release one more time on 2.x before the upgrade to drop 4.x node.

But just now we are frozen by some yarn/cloudflare/npmjs issue.

[devoto13]

@johnjbarton What is the issue? Anything I can help with?

[johnjbarton]

https://travis-ci.org/karma-runner/karma/jobs/385281416 yarn install v1.3.2 [1/5] Validating package.json... [2/5] Resolving packages... error Received malformed response from registry for undefined. The registry may be down. info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command. The command "eval yarn " failed. Retrying, 2 of 3.

…

On Tue, May 29, 2018 at 9:57 AM, Yaroslav Admin ***@***.***> wrote: @johnjbarton <https://github.com/johnjbarton> What is the issue? Anything I can help with? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#3016 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAMjAv4KdmmROwENNJxsvIlHR-x2I_Rzks5t3X34gaJpZM4UMzlf> .

[johnjbarton]

As I suspected, the issue resolved itself.

[lusarz]

@johnjbarton, @devoto13 any update on that ? Is there anything that stop us from removing Node 4 support ?

[johnjbarton]

Next week I will try to:

1. release one more 2.x version,
2. update 3.0 dropping node 4 and log4js 2.x

[johnjbarton]

Fixed by #3082