Support MTS TypeScript files

[rorymalcolm]

Describe the enhancement

As of TypeScript 4.5, TypeScript supports .mts and .cts files as possible extensions. Linguist should recognise these files as TypeScript files and highlight / index them accordingly.

[lildude]

I suspect you didn't plan on closing this so I'm reopening. I also think you mean .cts and not .mcs.

Please note, support won't be added, ie any PR adding support won't be merged, until there is widespread use of the extensions (see CONTRIBUTING.md).

[rorymalcolm]

I suspect you didn't plan on closing this so I'm reopening. I also think you mean .cts and not .mcs.

Please note, support won't be added, ie any PR adding support won't be merged, until there is widespread use of the extensions (see CONTRIBUTING.md).

Hi, I did mean to close, although it's in wide use on GitHub (mostly within node_modules folders), official support has been delayed and therefore I didn't want to commit to it.

[Nixinova]

MTS is used in 2K+ repos even when I restrict search to just node_modules/*/index.d.mts, so that should be alright at least. (link)

[rorymalcolm]

MTS is used in 2K+ repos even when I restrict search to just node_modules/*/index.d.mts, so that should be alright at least. (link)

Yeah althought it has widespread usage and semi support it's still the case that its not official yet, was meant to be in TS 4.6 but has since potentially slipped, see: microsoft/TypeScript#46452 for further info

[Inkdpixels]

@rorymalcolm Not sure if it really slipped, the issue you are referencing states that this is the standard that they are aiming to establish, no?

Also the .mts / . cts extensions are announced in the 4.7 beta blog post

https://devblogs.microsoft.com/typescript/announcing-typescript-4-7-beta/#new-file-extensions

[rorymalcolm]

@rorymalcolm Not sure if it really slipped, the issue you are referencing states that this is the standard that they are aiming to establish, no?

Also the .mts / . cts extensions are announced in the 4.7 beta blog post

https://devblogs.microsoft.com/typescript/announcing-typescript-4-7-beta/#new-file-extensions

Hadn't seen their inclusion 4.7's beta, probably fine, I just was aware there was some debate over it in the community when I wrote that comment months ago!