New `lsp-lens-place-position` default is arguably surprising

[michaelpj]

The LSP spec says nothing about where lenses are to be placed, which makes things tricky, however it's not uncommon for servers to assume that the behaviour is going to match VSCode, which places them above the line. This can matter, e.g. the Haskell server uses code lenses to display type signatures for functions that are missing them, and inserts them on click. Type signatures go above the declaration, not to the right, so putting the lens on the end of the line looks quite weird.

We've had a couple of users confused about this so far. It would be reasonable to say that the spec doesn't say where it should go, so you can't make any assumptions, but it seems to make lenses much harder to design, so 🤷

[yyoncho]

Agree. VScode behaviour should be the default.

[yyoncho]

Actually, I think that we decided to move it there because over the line does not work well(cc @ericdallo )

[ericdallo]

I think we should maybe have default for languages.
The issue with having above is that it's way worst when coding and see lines becoming bigger and smaller because lens are changing, I really think that should not be the default, the same happens with vscode and I saw lots of users complaining about the same.

As last resource IMO we should consider changing the default for specific langs only.

[yyoncho]

As last resource IMO we should consider changing the default for specific langs only.

I am generally against language specific defaults. They cause trouble.

[ericdallo]

Usually, I think we should match vscode, but this is one feature I disagree, VSCode itself doesn't support showing lens on the end of the file and if they do I bet lots of users would like since they have the same issue of emacs where lines keep changing because lens are being added or removed or re-calculated.

[ericdallo]

vim supports lens and IIRC are placed on the end of the line as well

[michaelpj]

I think there's a spec issue, I really think it should give some guidance about where lenses appear. I made an issue: microsoft/language-server-protocol#1558

I totally buy the argument that above-line is a bit dodgy, I observed that myself, and I do like having an option. It just means that at the moment people will get a weird experience with HLS. But maybe HLS is making bad assumptions!

[ericdallo]

Thanks for that!
Yeah, I can see how convenient changing the default for a lang may be, because lens can offer different features, since show references of a function to show function signature, that's why I thought about having this specific feature with different values by lang