Format type signatures in hover tooltip

[tanishiking]

Is your feature request related to a problem? Please describe.

When we hover on a symbol whose type signature is complex (e.g. check method in Metals), we'll see the following type signature that is cluttered and hard to read.

Describe the solution you'd like

It would be awesome if the type signature in the hover tooltip is formatted like

  def check(
      name: TestOptions,
      original: String,
      expected: String,
      includeDocs: Boolean = false,
      includeCommitCharacter: Boolean = false,
      compat: Map[String, String] = Map.empty,
      postProcessObtained: String => String = identity,
      stableOrder: Boolean = true,
      topLines: Option[Int] = None,
      filterText: String = "",
      includeDetail: Boolean = true,
      filename: String = "A.scala",
      filter: String => Boolean = _ => true,
      enablePackageWrap: Boolean = true,
  )(implicit loc: Location): Unit

instead of packing everything in one line. (not sure it's possible though).

Describe alternatives you've considered

not sure

Additional context

hover

Search terms

hover, type signature

[jkciesluk]

I think we can change it here

https://github.com/scalameta/metals/blob/1addbf1044ba2f5a37a8664c68a822ad0de026ee/mtags/src/main/scala-3/scala/meta/internal/pc/printer/MetalsPrinter.scala#L293-L319

The question is, should we always format or only if the definition is complex? If so, how we define complex?

[tanishiking]

I was thinking maybe we can apply scalafmt over the signatures (with appropriate column setting), but it's not ideal because maybe it takes some additional time to show the signatures.

Alternatively, maybe we can define the complexity based on the number of parameters 🤔