feat(lsp): more information on LSP errors

When the rust-analyzer server emits errors or warnings,
display the additional message. Don't de-duplicate messages
otherwise we loose the feedback on whether we have solved
the issue.

CHANGELOG.md

@@ -6,6 +6,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Added
+
+- LSP: Add more information to rust-analyzer unhealthy notifications
+
 ## [5.6.0] - 2024-09-18
 
 ### Added

lua/rustaceanvim/config/internal.lua

@@ -10,6 +10,7 @@ local RustaceanConfig
 ---@class rustaceanvim.internal.RAInitializedStatus : rustaceanvim.RAInitializedStatus
 ---@field health rustaceanvim.lsp_server_health_status
 ---@field quiescent boolean inactive?
+---@field message string | nil
 ---
 ---@param dap_adapter rustaceanvim.dap.executable.Config | rustaceanvim.dap.server.Config | rustaceanvim.disable
 ---@return boolean

lua/rustaceanvim/server_status.lua

@@ -7,11 +7,21 @@ local _ran_once = {}
 
 ---@param result rustaceanvim.internal.RAInitializedStatus
 function M.handler(_, result, ctx, _)
-  if result and result.health and result.health ~= 'ok' then
-    vim.notify_once("rust-analyzer health is not OK. Run 'RustLsp logFile' for details", vim.log.levels.WARN)
-  end
   -- quiescent means the full set of results is ready.
-  if not result.quiescent or _ran_once[ctx.client_id] then
+  if not result or not result.quiescent then
+    return
+  end
+  -- notify of LSP errors/warnings
+  if result.health and result.health ~= 'ok' then
+    local message = ([[
+rust-analyzer health status is [%s]:
+%s
+Run ':RustLsp logFile' for details.
+]]):format(result.health, result.message or "[unknown error]")
+    vim.notify(message, vim.log.levels.WARN)
+  end
+  -- deduplicate messages.
+  if _ran_once[ctx.client_id] then
     return
   end
   -- rust-analyzer may provide incomplete/empty inlay hints by the time Neovim