feat(init): warn if nvim-lspconfig.rust_analyzer setup detected

Author: Marc Jakobi

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).
 
+## [4.16.0] - 2024-03-24
+
+### Added
+
+- Initialization: Warn if nvim-lspconfig.rust-analyzer setup is detected.
+
 ## [4.15.0] - 2024-03-24
 
 ### Added

README.md

@@ -801,15 +801,20 @@ For issues related to rust-analyzer
 (e.g. LSP features not working), see also
 [the rust-analyzer troubleshooting guide](https://rust-analyzer.github.io/manual.html#troubleshooting).
 
-## FAQ
+### FAQ
 
-### Where are inlay hints?
+#### Where are inlay hints?
 
 As Neovim >= 0.10 supports inlay hints natively, I have removed the
 code from this plugin.
 
 To enable inlay hints in Neovim < 0.10, see [this discussion](https://github.com/mrcjkb/rustaceanvim/discussions/46#discussioncomment-7620822).
 
+#### mason.nvim and nvim-lspconfig
+
+See [`:h rustaceanvim.mason`](./doc/mason.txt) for details about troubleshooting
+mason.nvim and nvim-lspconfig issues.
+
 ## Related Projects
 
 - [`rouge8/neotest-rust`](https://github.com/rouge8/neotest-rust)

doc/mason.txt

@@ -0,0 +1,39 @@
+==============================================================================
+mason-lspconfig troubleshooting                          *rustaceanvim.mason*
+
+This plugin supports automatically detecting mason.nvim codelldb installations,
+but not rust-analyzer.
+The main reason for this choice is that it mason.nvim installations of rust-analyzer
+will most likely have been built with a different toolchain than your project,
+leading to inconsistencies and possibly subtle bugs.
+If you want to use a mason.nvim installation anyway, you can do so by specifying
+the `server.cmd` setting (see |rustaceanvim.config| and |RustaceanLspClientOpts|).
+
+Note that mason-lspconfig.nvim, when configured to ensure rust-analyzer is installed,
+assumes you are using the `nvim-lspconfig.rust_analyzer` client,
+and will set it up for you, leading to conflicts with this plugin.
+You can prevent this by telling mason.nvim not to do so.
+
+General approach:
+
+>lua
+  require('mason-lspconfig').setup_handlers {
+    ['rust_analyzer'] = function() end,
+  }
+<
+
+Using LazyVim:
+
+>lua
+  {
+    'neovim/nvim-lspconfig',
+    opts = {
+      setup = {
+        rust_analyzer = function()
+          return true 
+        end,
+      },
+    },
+  }
+<
+vim:tw=78:ts=8:noet:ft=help:norl:

ftplugin/rust.lua

@@ -2,6 +2,9 @@
 local config = require('rustaceanvim.config.internal')
 
 if not vim.g.did_rustaceanvim_initialize then
+  require('rustaceanvim.config.check').check_for_lspconfig_conflict(vim.schedule_wrap(function(warn)
+    vim.notify_once(warn, vim.log.levels.WARN)
+  end))
   vim.lsp.commands['rust-analyzer.runSingle'] = function(command)
     local runnables = require('rustaceanvim.runnables')
     local cached_commands = require('rustaceanvim.cached_commands')

lua/rustaceanvim/config/check.lua

@@ -137,4 +137,23 @@ function M.validate(cfg)
   return true
 end
 
+---@param callback fun(msg: string)
+function M.check_for_lspconfig_conflict(callback)
+  for _, autocmd in ipairs(vim.api.nvim_get_autocmds { event = 'FileType', pattern = 'rust' }) do
+    if
+      autocmd.group_name
+      and autocmd.group_name == 'lspconfig'
+      and autocmd.desc
+      and autocmd.desc:match('rust_analyzer')
+    then
+      callback([[
+nvim-lspconfig.rust_analyzer has been setup.
+This will likely lead to conflicts with the rustaceanvim LSP client.
+See ':h rustaceanvim.mason'
+]])
+      return
+    end
+  end
+end
+
 return M

lua/rustaceanvim/health.lua

@@ -125,19 +125,7 @@ end
 
 local function check_for_conflicts()
   start('Checking for conflicting plugins')
-  for _, autocmd in ipairs(vim.api.nvim_get_autocmds { event = 'FileType', pattern = 'rust' }) do
-    if
-      autocmd.group_name
-      and autocmd.group_name == 'lspconfig'
-      and autocmd.desc
-      and autocmd.desc:match('rust_analyzer')
-    then
-      error(
-        'lspconfig.rust_analyzer has been setup. This will likely lead to conflicts with the rustaceanvim LSP client.'
-      )
-      return
-    end
-  end
+  require('rustaceanvim.config.check').check_for_lspconfig_conflict(error)
   if package.loaded['rustaceanvim.neotest'] ~= nil and package.loaded['neotest-rust'] ~= nil then
     error('rustaceanvim.neotest and neotest-rust are both loaded. This is likely a conflict.')
     return