Breaking: Support TypeScript 2.3 (fixes #232)

[azz]

Seems to be a minor fix.

[eslintbot]

LGTM

[JamesHenry]

Thanks for the quick digging, @azz!

The fact that this didn't break any existing tests is a clear sign that we should add some as part of this change. Please can you add a relevant JSX test?

Many thanks!

[JamesHenry]

Also, we would class this a Breaking change, and so the commit message needs to reflect that for our release process to work accordingly.

Reference: http://eslint.org/docs/developer-guide/contributing/pull-requests

[azz]

I was just about to amend the commit to be backwards compatible. Is that something you want me to do?

[JamesHenry]

Us changing the officially supported TypeScript version should basically always be a breaking change I think, in order to offer clear indication to our users that they will likely need to make changes to their setups

[JamesHenry]

We have two other pending breaking changes to make, so this is great timing!

[eslintbot]

LGTM

[azz]

The fact that this didn't break any existing tests is a clear sign that we should add some as part of this change. Please can you add a relevant JSX test?

Not sure what you mean by this. The tests did fail until this change, and the change itself it backwards compatible.

[JamesHenry]

RE: The tests - Yes, sorry, I misread the type of change we were making at first.

In terms of backwards compatibility, you added that change and comment after I first looked at it. Please can you remove them again?

I really appreciate we you are trying to do with that, but if we added comments and "version bridges" for every TypeScript version upgrade, this project would become very difficult to manage. This upgrade is trivial, but previous ones were not at all. TypeScript does not follow a strict semver policy, and as mentioned before, the AST structure is naturally not respected at all when it comes to version numbers.

By classifying it as a breaking change, we will automatically release a new major version of the parser and the intention to our users is as clear as it can be.

[eslintbot]

LGTM

[azz]

TypeScript does not follow a strict semver policy.

I learnt that the hard way when 2.1 came out...

In terms of backwards compatibility, you added that change and comment after I first looked at it. Please can you remove them again?

Done.

[JamesHenry]

Thanks a lot!

[JamesHenry]

We'll get this in with the other breaking changes and release a new major version 🎉