PHP 5 runtime support

[felixfbecker]

We would lose the following features:

• scalar type hinting
• return type annotations
• group use statements
• anonymous classes
• ?? operator

Is there anything like BabelJS for PHP that transpiles it?

[felixfbecker]

Since a lot of people ask for this: I like the new features of PHP 7 and use PHP 7 in all my projects. I understand though that many do not. So if you care about this, and want to do the refactoring work (low hanging fruit really compared to other features), I will happily merge a PR, but I myself will rather concentrate on features. I would also prefer a transpilation solution if that is possible.

[batopa]

I found this PHP transpiler https://github.com/jaytaph/Transphpile but I don't know if it works well.
Anyway if it works well how should work the transpiling action? I mean do you intend to release two version of the plugin or what?

[felixfbecker]

@batopa I would write the source in PHP 7, but before releasing transpile to PHP 5.

Actually, I don't know atm if Composer supports this. I come from a Node background and on NPM it is pretty common to transpile code before releasing...

[batopa]

Composer permits something similar https://getcomposer.org/doc/articles/scripts.md.
How do you have to release the package for work in vscode?

[felixfbecker]

The VS Code extension has a composer.json and the vendor directory is bundled with each release.

[felixfbecker]

So we would add the transpiler as devdep and call it in a post-package-install script?

[batopa]

Yes that is the idea. But frankly for me it would be preferable to have two versions of the plugin. The transpiler seems immature and use it for production seems risky to me.

Having something like a stable version for PHP >= 7 and a preview version transpiled for PHP 5.6.

[felixfbecker]

I am against two versions. We should rather find a way to only transpile src, not tests, and then run the tests against the transpiled version (in CI). Only need to modify the autoloading to point to the dist folder. That way we can 100% verify everything works (well, 90% with current coverage :P).

[batopa]

Meanwhile I'll have a look at transpiler to see how it works

[batopa]

The issue is more complicated than I expected.
The thing is that we need to transpile src and test and also the vendor package AdvancedJsonRpc (src and test) that require PHP 7. Then we should run tests against the transpiled version both in php-language-server and in php-advanced-json-rpc

The transpiler works quite well but I have some issues with anonymous classes (I found it in \LanguageServer\Tests\Server\TextDocumentTest) and other little things.

[felixfbecker]

Since Im the author of that lib as well it's no problem to transpile it as well :)
The anonymous class could get replaced by some mocking framework.

[Ciantic]

Does this mean the Language Server should run in PHP 5? Or does this mean it should be able to parse PHP 5?

When people ask for PHP 5 support, they probably mean their code is in PHP 5 and think since this runs on PHP 7, their code can't be parsed / validated. Even though it seems to work just fine on my PHP 5 source files.

I think having language server written as PHP 5 is useless waste of time, since this project works just fine with PHP 5 source files. Developers can easily install PHP 7 just for running the language server IMHO.

[felixfbecker]

@Ciantic this is just about running the language server in PHP so people don't have to install two versions side-by-side. Parsing PHP 5 is totally fine, and depends only on the PHPParser. As I stated, I will not put any work into this, but if someone wants to set up a transpilation solution I would merge a PR.

[felixfbecker]

Declining this because some dependencies require PHP 7 now.
Please note that parsing PHP5 files is and has always been supported.