Pretty-printing of diagnostics coming from PublishDiagnosticsParams

[Boscop]

In a LSP client talking to rust-analyzer, I'd like to pretty-print diagnostics coming from PublishDiagnosticsParams, so that they look readable/indented, ideally exactly like when cargo shows errors (but without terminal color codes).
https://docs.rs/lsp-types/latest/lsp_types/struct.Diagnostic.html

Is there a function in some crate already that does this? 🙂

How do editors who have LSP clients do this, does every one reimplement the diagnostic fomatting?