TypeScript definite assignment assertions are not removed for private class fields

[elisee]

Hi! Thanks for a great tool, it's been wonderful using it for instant TypeScript-to-JavaScript conversion in my projects.

The TypeScript transform should remove the ! definite assignment assertion for private class fields:

class A { #b!; }

The expected result is:

class A { #b; }

But instead, the ! is currently kept.

Example: https://sucrase.io/#selectedTransforms=typescript&code=class%20A%20%7B%20%23b!%3B%20%7D

[Rugvip]

Afaik that syntax is not valid in TypeScript, and this seems to compile alright:

class A { #b!: number }

[elisee]

My bad, I guess I went too far with minimizing the test case. Still, I believe this:

class A { #b!: number; }

Should compile down to this:

class A { #b; }

not this, which isn't valid JavaScript:

class A { #b!; }

[alangpierce]

Thanks for reporting! A related problem I found while investigating is that even non-private fields have problems here when using disableESTransforms: true. For example, this:

class A { b!: number; }

becomes this:

class A { b!; }

I think I have a fix working, will put up a PR soon.