feat(lsp): auto-detect some extra plugin client capabilities

Author: Marc Jakobi

CHANGELOG.md

@@ -8,6 +8,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- LSP: Automatically detect and register client capabilities for the following plugins,
+  if installed:
+  - [cmp-nvim-lsp](https://github.com/hrsh7th/cmp-nvim-lsp)
+  - [nvim-lsp-selection-range](https://github.com/camilledejoye/nvim-lsp-selection-range)
+  - [nvim-ufo](https://github.com/kevinhwang91/nvim-ufo)
+
 ### Fixed
 
 - Neotest: Correctly mark passed and skipped tests when running a

lua/rustaceanvim/config/internal.lua

@@ -3,6 +3,7 @@ local compat = require('rustaceanvim.compat')
 local config = require('rustaceanvim.config')
 local executors = require('rustaceanvim.executors')
 local os = require('rustaceanvim.os')
+local server_config = require('rustaceanvim.config.server')
 
 local RustaceanConfig
 
@@ -263,6 +264,8 @@ local RustaceanDefaultConfig = {
   ---@diagnostic disable-next-line: undefined-doc-class
   ---@class RustaceanLspClientConfig: vim.lsp.ClientConfig
   server = {
+    ---@type rustaceanvim.ClientCapabilities
+    capabilities = server_config.create_client_capabilities(),
     ---@type boolean | fun(bufnr: integer):boolean Whether to automatically attach the LSP client.
     ---Defaults to `true` if the `rust-analyzer` executable is found.
     auto_attach = function(bufnr)
@@ -292,10 +295,7 @@ local RustaceanDefaultConfig = {
 
     ---@type table | (fun(project_root:string|nil, default_settings: table|nil):table) -- The rust-analyzer settings or a function that creates them.
     settings = function(project_root, default_settings)
-      return require('rustaceanvim.config.server').load_rust_analyzer_settings(
-        project_root,
-        { default_settings = default_settings }
-      )
+      return server_config.load_rust_analyzer_settings(project_root, { default_settings = default_settings })
     end,
 
     --- @type table

lua/rustaceanvim/config/server.lua

@@ -63,4 +63,89 @@ function server.load_rust_analyzer_settings(project_root, opts)
   return default_settings
 end
 
+---@return rustaceanvim.ClientCapabilities
+local function make_rustaceanvim_capabilities()
+  ---@class rustaceanvim.ClientCapabilities: lsp.ClientCapabilities
+  local capabilities = vim.lsp.protocol.make_client_capabilities()
+
+  -- snippets
+  capabilities.textDocument.completion.completionItem.snippetSupport = true
+
+  -- send actions with hover request
+  ---@class rustaceanvim.ExperimentalCapabilities
+  capabilities.experimental = {
+    hoverActions = true,
+    hoverRange = true,
+    serverStatusNotification = true,
+    snippetTextEdit = true,
+    codeActionGroup = true,
+    ssr = true,
+  }
+
+  -- enable auto-import
+  capabilities.textDocument.completion.completionItem.resolveSupport = {
+    properties = { 'documentation', 'detail', 'additionalTextEdits' },
+  }
+
+  -- rust analyzer goodies
+  local experimental_commands = {
+    'rust-analyzer.runSingle',
+    'rust-analyzer.showReferences',
+    'rust-analyzer.gotoLocation',
+    'editor.action.triggerParameterHints',
+  }
+  if package.loaded['dap'] ~= nil then
+    table.insert(experimental_commands, 'rust-analyzer.debugSingle')
+  end
+
+  ---@class rustaceanvim.ExperimentalCommandCapabilities
+  capabilities.experimental.commands = {
+    commands = experimental_commands,
+  }
+
+  return capabilities
+end
+
+---@param mod_name string
+---@param callback fun(mod: table): lsp.ClientCapabilities
+---@return lsp.ClientCapabilities
+local function mk_capabilities_if_available(mod_name, callback)
+  local available, mod = pcall(require, mod_name)
+  if available and type(mod) == 'table' then
+    local ok, capabilities = pcall(callback, mod)
+    if ok then
+      return capabilities
+    end
+  end
+  return {}
+end
+
+---@return rustaceanvim.ClientCapabilities
+function server.create_client_capabilities()
+  local rs_capabilities = make_rustaceanvim_capabilities()
+  local cmp_capabilities = mk_capabilities_if_available('cmp_nvim_lsp', function(cmp_nvim_lsp)
+    return cmp_nvim_lsp.default_capabilities()
+  end)
+  local selection_range_capabilities = mk_capabilities_if_available('lsp-selection-range', function(lsp_selection_range)
+    return lsp_selection_range.update_capabilities {}
+  end)
+  local folding_range_capabilities = mk_capabilities_if_available('ufo', function(_)
+    return {
+      textDocument = {
+        foldingRange = {
+          dynamicRegistration = false,
+          lineFoldingOnly = true,
+        },
+      },
+    }
+  end)
+  return vim.tbl_deep_extend(
+    'keep',
+    rs_capabilities,
+    cmp_capabilities,
+    selection_range_capabilities,
+    folding_range_capabilities
+  )
+end
+
 return server

lua/rustaceanvim/lsp.lua

@@ -135,42 +135,6 @@ M.start = function(bufnr)
   lsp_start_config.cmd = rust_analyzer_cmd
   lsp_start_config.name = 'rust-analyzer'
   lsp_start_config.filetypes = { 'rust' }
-  local capabilities = vim.lsp.protocol.make_client_capabilities()
-
-  -- snippets
-  capabilities.textDocument.completion.completionItem.snippetSupport = true
-
-  -- send actions with hover request
-  capabilities.experimental = {
-    hoverActions = true,
-    hoverRange = true,
-    serverStatusNotification = true,
-    snippetTextEdit = true,
-    codeActionGroup = true,
-    ssr = true,
-  }
-
-  -- enable auto-import
-  capabilities.textDocument.completion.completionItem.resolveSupport = {
-    properties = { 'documentation', 'detail', 'additionalTextEdits' },
-  }
-
-  -- rust analyzer goodies
-  local experimental_commands = {
-    'rust-analyzer.runSingle',
-    'rust-analyzer.showReferences',
-    'rust-analyzer.gotoLocation',
-    'editor.action.triggerParameterHints',
-  }
-  if package.loaded['dap'] ~= nil then
-    table.insert(experimental_commands, 'rust-analyzer.debugSingle')
-  end
-
-  capabilities.experimental.commands = {
-    commands = experimental_commands,
-  }
-
-  lsp_start_config.capabilities = vim.tbl_deep_extend('force', capabilities, lsp_start_config.capabilities or {})
 
   local custom_handlers = {}
   custom_handlers['experimental/serverStatus'] = server_status.handler