[javascript] Bring back ES6 syntax highlighting support

[txchen]

Right now, those keywords like import class from are all plain white.

[leafduo]

And async from ES7 seems to be interpreted to TypeScript keyword.

[jahewson]

+1. Also => needs to be in a separate syntax class from the operators that are keywords, such as instanceof because I want to color keywords separately from =>. Also for import * as 'foo' import and as need to be keywords while * needs to be either an operator or something else more specific to imports.

[aeschli]

Our colorizer doesn't support ES6 / ES7 yet. I will look for a text mate grammar that does that.

[jnystrom]

@aeschli I thought for sure ES6 template strings were handled fairly well in the previous version of VSCode.

[aeschli]

@jnystrom Yes, it's a regression, we switched from our own tokenizer to a JavaScript text mate grammar.

[egamma]

Plan is to use the TypeScript provided textmate grammar for JavaScript

[aeschli]

New grammar based on TypeScript grammar delivered.

[aeschli]

To try this out on a November release (0.10.1 - 3), replace the content of
Microsoft VS Code/resources/app/extensions/javascript/syntaxes/JavaScript.tmLanguage
with
https://github.com/Microsoft/vscode/raw/0b3f7b223d86ac1e8bbebc670913ed83595e98c6/extensions/javascript/syntaxes/JavaScript.tmLanguage

[konrad-garus]

I tried the workaround from @aeschli, restarted Code, but still keywords like yield are not highlighted. This is 0.10.6 on Ubuntu.

[aeschli]

@konrad-garus yield is still not colored due to bug microsoft/TypeScript-TmLanguage#29