TypeScript expandable hover

[liuzhch-Orka]

This feature is implemented by VSCode itself, and was previously implemented by the Prettify TS plugin.

Current typescript type display of Zed:

Expected:

[CL-Jeremy]

TypeScript 5.9 Beta dropped with this feature in preview: https://devblogs.microsoft.com/typescript/announcing-typescript-5-9-beta/#expandable-hovers-(preview), allowing VS Code to implement it with a + button to manually toggle verbosity. To be fair I'd prefer toggling it with alt/command, but either way it'd be nice to have this feature in Zed.

[SimonSimCity]

The feature was implemented in vscode in this PR: microsoft/vscode#228255

But most of the details seem to be part of the counterpart PR in the typescript repo, where I specifically want to point at this comment: microsoft/TypeScript#59940 (comment)
Where I found this:

The feature will be available via our TSServer API. Any editor using that API will have access to it. Note though that TSServer API is not LSP compatible.

[CL-Jeremy]

Thanks for pointing this out. So we'd probably have to wait till this (hover verbosity level) gets addressed in an LSP spec update then. Makes sense to wait, though. Alternatively, an experimental fork might be created for vtsls with a private extension to the LSP spec to accommodate this change. Hopefully Microsoft has thought about this already...

[valerii15298]

typescript-go will have native lsp support which would obsolete vtsls so I think it makes sense to wait for typescript-go release.
For now typescript go only supports typescript 5.8 features which do not include expandable hover

[radiosilence]

This feature would be absolutely amazing, as there's often zero way to actually find what something is.