output aliased types in typescript declarations

[43081j]

Q	A
Fixed Issues?	N/A
Patch: Bug Fix?	Y
Major: Breaking Change?	N
Minor: New Feature?	N
Tests Added + Pass?	N/Y
Documentation PR Link	N/A
Any Dependency Changes?	N
License	MIT

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We weren't outputting aliased types in our isXX assertion methods so we would be losing type information (returning boolean instead).

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/9022/

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/9022/

[xtuc]

Please add tests

[43081j]

Do we have any tests for the generators at all? I'm happy to write some but wasn't sure if we already had any I could extend.

[xtuc]

Yes that's right, sorry.

[xtuc]

I think it doesn't make sense to add tests on the generator, we could instead just commit the file, but the point is to avoid that.

[43081j]

No worries.

It's possible to write tests but they would be type tests rather than unit. Similar to how definitelytyped works. You have a usage file and assert that it compiles.

Maybe something for the future.

[43081j]

Could we get some eyes on this and possibly merge it? Its a very small change but we can't use the shipped TS definitions until then