feat(lsp): use stricter types for methods

This change modifies gen_lsp.lua so alias types are generated for
various types of lsp methods to distinguish between notifications
and requests:
 - vim.lsp.protocol.Method.ServerToClient.Request
 - vim.lsp.protocol.Method.ServerToClient.Notification
 - vim.lsp.protocol.Method.ClientToServer.Request
 - vim.lsp.protocol.Method.ClientToServer.Notification

 These types are then used instead of `string` where appropriate.

runtime/lua/vim/lsp.lua

@@ -1285,7 +1285,7 @@ end
 ---@since 7
 ---
 ---@param bufnr integer Buffer handle, or 0 for current.
----@param method string LSP method name
+---@param method vim.lsp.protocol.Method.ClientToServer.Request LSP method name
 ---@param params? table|(fun(client: vim.lsp.Client, bufnr: integer): table?) Parameters to send to the server.
 ---               Can also be passed as a function that returns the params table for cases where
 ---               parameters are specific to the client.

runtime/lua/vim/lsp/_meta/protocol.lua

@@ -1,11 +1,11 @@
 --[[
-THIS FILE IS GENERATED by scripts/gen_lsp.lua
+THIS FILE IS GENERATED by scr/gen/gen_lsp.lua
 DO NOT EDIT MANUALLY
 
 Based on LSP protocol 3.18
 
 Regenerate:
-nvim -l scripts/gen_lsp.lua gen --version 3.18
+nvim -l scr/gen/gen_lsp.lua gen --version 3.18
 --]]
 
 ---@meta

runtime/lua/vim/lsp/buf.lua

@@ -158,7 +158,7 @@ local function request_with_opts(name, params, opts)
   lsp.buf_request(0, name, params, req_handler)
 end
 
----@param method string
+---@param method vim.lsp.protocol.Method.ClientToServer.Request
 ---@param opts? vim.lsp.LocationOpts
 local function get_locations(method, opts)
   opts = opts or {}
@@ -814,7 +814,7 @@ function M.document_symbol(opts)
 end
 
 --- @param client_id integer
---- @param method string
+--- @param method vim.lsp.protocol.Method.ClientToServer.Request
 --- @param params table
 --- @param handler? lsp.Handler
 --- @param bufnr? integer
@@ -845,7 +845,7 @@ local hierarchy_methods = {
   [ms.callHierarchy_outgoingCalls] = 'call',
 }
 
---- @param method string
+--- @param method vim.lsp.protocol.Method.ClientToServer.Request
 local function hierarchy(method)
   local kind = hierarchy_methods[method]
   if not kind then

runtime/lua/vim/lsp/client.lua

@@ -656,7 +656,7 @@ end
 --- This is a thin wrapper around {client.rpc.request} with some additional
 --- checks for capabilities and handler availability.
 ---
---- @param method string LSP method name.
+--- @param method vim.lsp.protocol.Method.ClientToServer.Request LSP method name.
 --- @param params? table LSP request params.
 --- @param handler? lsp.Handler Response |lsp-handler| for this method.
 --- @param bufnr? integer (default: 0) Buffer handle, or 0 for current.
@@ -721,7 +721,7 @@ end
 ---
 --- This is a wrapper around |Client:request()|
 ---
---- @param method string LSP method name.
+--- @param method vim.lsp.protocol.Method.ClientToServer.Request LSP method name.
 --- @param params table LSP request params.
 --- @param timeout_ms integer? Maximum time in milliseconds to wait for
 ---                                a result. Defaults to 1000
@@ -757,7 +757,7 @@ end
 
 --- Sends a notification to an LSP server.
 ---
---- @param method string LSP method name.
+--- @param method vim.lsp.protocol.Method.ClientToServer.Notification LSP method name.
 --- @param params table? LSP request params.
 --- @return boolean status indicating if the notification was successful.
 ---                        If it is false, then the client has shutdown.
@@ -828,7 +828,7 @@ function Client:stop(force)
 end
 
 --- Get options for a method that is registered dynamically.
---- @param method string
+--- @param method vim.lsp.protocol.Method
 function Client:_supports_registration(method)
   local capability = vim.tbl_get(self.capabilities, unpack(vim.split(method, '/')))
   return type(capability) == 'table' and capability.dynamicRegistration
@@ -901,7 +901,7 @@ function Client:_get_language_id(bufnr)
   return self.get_language_id(bufnr, vim.bo[bufnr].filetype)
 end
 
---- @param method string
+--- @param method vim.lsp.protocol.Method
 --- @param bufnr? integer
 --- @return lsp.Registration?
 function Client:_get_registration(method, bufnr)
@@ -1051,7 +1051,7 @@ end
 --- Always returns true for unknown off-spec methods.
 ---
 --- Note: Some language server capabilities can be file specific.
---- @param method string
+--- @param method vim.lsp.protocol.Method.ClientToServer
 --- @param bufnr? integer
 function Client:supports_method(method, bufnr)
   -- Deprecated form
@@ -1082,27 +1082,11 @@ function Client:supports_method(method, bufnr)
   return false
 end
 
---- Get options for a method that is registered dynamically.
---- @param method string
---- @param bufnr? integer
---- @return lsp.LSPAny?
-function Client:_get_registration_options(method, bufnr)
-  if not self:_supports_registration(method) then
-    return
-  end
-
-  local reg = self:_get_registration(method, bufnr)
-
-  if reg then
-    return reg.registerOptions
-  end
-end
-
 --- @private
 --- Handles a notification sent by an LSP server by invoking the
 --- corresponding handler.
 ---
---- @param method string LSP method name
+--- @param method vim.lsp.protocol.Method.ServerToClient.Notification LSP method name
 --- @param params table The parameters for that method.
 function Client:_notification(method, params)
   log.trace('notification', method, params)

runtime/lua/vim/lsp/protocol.lua

@@ -621,22 +621,15 @@ function protocol.resolve_capabilities(server_capabilities)
 end
 
 -- Generated by gen_lsp.lua, keep at end of file.
---- @alias vim.lsp.protocol.Method.ClientToServer
+--- @alias vim.lsp.protocol.Method.ClientToServer.Request
 --- | 'callHierarchy/incomingCalls',
 --- | 'callHierarchy/outgoingCalls',
 --- | 'codeAction/resolve',
 --- | 'codeLens/resolve',
 --- | 'completionItem/resolve',
 --- | 'documentLink/resolve',
---- | '$/setTrace',
---- | 'exit',
 --- | 'initialize',
---- | 'initialized',
 --- | 'inlayHint/resolve',
---- | 'notebookDocument/didChange',
---- | 'notebookDocument/didClose',
---- | 'notebookDocument/didOpen',
---- | 'notebookDocument/didSave',
 --- | 'shutdown',
 --- | 'textDocument/codeAction',
 --- | 'textDocument/codeLens',
@@ -645,10 +638,6 @@ end
 --- | 'textDocument/declaration',
 --- | 'textDocument/definition',
 --- | 'textDocument/diagnostic',
---- | 'textDocument/didChange',
---- | 'textDocument/didClose',
---- | 'textDocument/didOpen',
---- | 'textDocument/didSave',
 --- | 'textDocument/documentColor',
 --- | 'textDocument/documentHighlight',
 --- | 'textDocument/documentLink',
@@ -676,19 +665,11 @@ end
 --- | 'textDocument/semanticTokens/range',
 --- | 'textDocument/signatureHelp',
 --- | 'textDocument/typeDefinition',
---- | 'textDocument/willSave',
 --- | 'textDocument/willSaveWaitUntil',
 --- | 'typeHierarchy/subtypes',
 --- | 'typeHierarchy/supertypes',
---- | 'window/workDoneProgress/cancel',
 --- | 'workspaceSymbol/resolve',
 --- | 'workspace/diagnostic',
---- | 'workspace/didChangeConfiguration',
---- | 'workspace/didChangeWatchedFiles',
---- | 'workspace/didChangeWorkspaceFolders',
---- | 'workspace/didCreateFiles',
---- | 'workspace/didDeleteFiles',
---- | 'workspace/didRenameFiles',
 --- | 'workspace/executeCommand',
 --- | 'workspace/symbol',
 --- | 'workspace/textDocumentContent',
@@ -696,15 +677,35 @@ end
 --- | 'workspace/willDeleteFiles',
 --- | 'workspace/willRenameFiles',
 
---- @alias vim.lsp.protocol.Method.ServerToClient
+--- @alias vim.lsp.protocol.Method.ClientToServer.Notification
+--- | '$/setTrace',
+--- | 'exit',
+--- | 'initialized',
+--- | 'notebookDocument/didChange',
+--- | 'notebookDocument/didClose',
+--- | 'notebookDocument/didOpen',
+--- | 'notebookDocument/didSave',
+--- | 'textDocument/didChange',
+--- | 'textDocument/didClose',
+--- | 'textDocument/didOpen',
+--- | 'textDocument/didSave',
+--- | 'textDocument/willSave',
+--- | 'window/workDoneProgress/cancel',
+--- | 'workspace/didChangeConfiguration',
+--- | 'workspace/didChangeWatchedFiles',
+--- | 'workspace/didChangeWorkspaceFolders',
+--- | 'workspace/didCreateFiles',
+--- | 'workspace/didDeleteFiles',
+--- | 'workspace/didRenameFiles',
+
+--- @alias vim.lsp.protocol.Method.ClientToServer
+--- | vim.lsp.protocol.Method.ClientToServer.Request
+--- | vim.lsp.protocol.Method.ClientToServer.Notification
+
+--- @alias vim.lsp.protocol.Method.ServerToClient.Request
 --- | 'client/registerCapability',
 --- | 'client/unregisterCapability',
---- | '$/logTrace',
---- | 'telemetry/event',
---- | 'textDocument/publishDiagnostics',
---- | 'window/logMessage',
 --- | 'window/showDocument',
---- | 'window/showMessage',
 --- | 'window/showMessageRequest',
 --- | 'window/workDoneProgress/create',
 --- | 'workspace/applyEdit',
@@ -718,6 +719,17 @@ end
 --- | 'workspace/textDocumentContent/refresh',
 --- | 'workspace/workspaceFolders',
 
+--- @alias vim.lsp.protocol.Method.ServerToClient.Notification
+--- | '$/logTrace',
+--- | 'telemetry/event',
+--- | 'textDocument/publishDiagnostics',
+--- | 'window/logMessage',
+--- | 'window/showMessage',
+
+--- @alias vim.lsp.protocol.Method.ServerToClient
+--- | vim.lsp.protocol.Method.ServerToClient.Request
+--- | vim.lsp.protocol.Method.ServerToClient.Notification
+
 --- @alias vim.lsp.protocol.Method
 --- | vim.lsp.protocol.Method.ClientToServer
 --- | vim.lsp.protocol.Method.ServerToClient

runtime/lua/vim/lsp/util.lua

@@ -2164,7 +2164,7 @@ end
 ---@class (private) vim.lsp.util._cancel_requests.Filter
 ---@field bufnr? integer
 ---@field clients? vim.lsp.Client[]
----@field method? string
+---@field method? vim.lsp.protocol.Method.ClientToServer.Request
 ---@field type? string
 
 ---@private

src/gen/gen_lsp.lua

@@ -33,6 +33,24 @@ end
 --- @field enumerations vim._gen_lsp.Enumeration[]
 --- @field typeAliases vim._gen_lsp.TypeAlias[]
 
+--- @class vim._gen_lsp.Notification
+--- @field deprecated? string
+--- @field documentation? string
+--- @field messageDirection string
+--- @field clientCapability? string
+--- @field serverCapability? string
+--- @field method string
+--- @field params? any
+--- @field proposed? boolean
+--- @field registrationMethod? string
+--- @field registrationOptions? any
+--- @field since? string
+
+--- @class vim._gen_lsp.Request : vim._gen_lsp.Notification
+--- @field errorData? any
+--- @field partialResult? any
+--- @field result any
+
 ---@param opt vim._gen_lsp.opt
 ---@return vim._gen_lsp.Protocol
 local function read_json(opt)
@@ -66,64 +84,47 @@ local function write_to_protocol(protocol, gen_methods, gen_capabilities)
 
   local indent = (' '):rep(2)
 
-  --- @class vim._gen_lsp.Request
-  --- @field deprecated? string
-  --- @field documentation? string
-  --- @field messageDirection string
-  --- @field clientCapability? string
-  --- @field serverCapability? string
-  --- @field method string
-  --- @field params? any
-  --- @field proposed? boolean
-  --- @field registrationMethod? string
-  --- @field registrationOptions? any
-  --- @field since? string
-
-  --- @class vim._gen_lsp.Notification
-  --- @field deprecated? string
-  --- @field documentation? string
-  --- @field errorData? any
-  --- @field messageDirection string
-  --- @field clientCapability? string
-  --- @field serverCapability? string
-  --- @field method string
-  --- @field params? any[]
-  --- @field partialResult? any
-  --- @field proposed? boolean
-  --- @field registrationMethod? string
-  --- @field registrationOptions? any
-  --- @field result any
-  --- @field since? string
+  local function compare_method(a, b)
+    return to_luaname(a.method) < to_luaname(b.method)
+  end
 
   ---@type (vim._gen_lsp.Request|vim._gen_lsp.Notification)[]
-  local all = vim.list_extend(protocol.requests, protocol.notifications)
-  table.sort(all, function(a, b)
-    return to_luaname(a.method) < to_luaname(b.method)
-  end)
+  local all = {}
+  vim.list_extend(all, protocol.notifications)
+  vim.list_extend(all, protocol.requests)
+
+  table.sort(all, compare_method)
+  table.sort(protocol.requests, compare_method)
+  table.sort(protocol.notifications, compare_method)
 
   local output = { '-- Generated by gen_lsp.lua, keep at end of file.' }
 
   if gen_methods then
-    output[#output + 1] = '--- @alias vim.lsp.protocol.Method.ClientToServer'
-
-    for _, item in ipairs(all) do
-      if item.method and item.messageDirection == 'clientToServer' then
-        output[#output + 1] = ("--- | '%s',"):format(item.method)
+    for _, dir in ipairs({ 'clientToServer', 'serverToClient' }) do
+      local dir1 = dir:sub(1, 1):upper() .. dir:sub(2)
+      local alias = ('vim.lsp.protocol.Method.%s'):format(dir1)
+      for _, b in ipairs({
+        { title = 'Request', methods = protocol.requests },
+        { title = 'Notification', methods = protocol.notifications },
+      }) do
+        output[#output + 1] = ('--- @alias %s.%s'):format(alias, b.title)
+        for _, item in ipairs(b.methods) do
+          if item.messageDirection == dir then
+            output[#output + 1] = ("--- | '%s',"):format(item.method)
+          end
+        end
+        output[#output + 1] = ''
       end
+
+      vim.list_extend(output, {
+        ('--- @alias %s'):format(alias),
+        ('--- | %s.Request'):format(alias),
+        ('--- | %s.Notification'):format(alias),
+        '',
+      })
     end
 
     vim.list_extend(output, {
-      '',
-      '--- @alias vim.lsp.protocol.Method.ServerToClient',
-    })
-    for _, item in ipairs(all) do
-      if item.method and item.messageDirection == 'serverToClient' then
-        output[#output + 1] = ("--- | '%s',"):format(item.method)
-      end
-    end
-
-    vim.list_extend(output, {
-      '',
       '--- @alias vim.lsp.protocol.Method',
       '--- | vim.lsp.protocol.Method.ClientToServer',
       '--- | vim.lsp.protocol.Method.ServerToClient',

src/gen/gen_vimdoc.lua

@@ -427,6 +427,9 @@ end
 --- @param generics? table<string,string>
 --- @param default? string
 local function render_type(ty, generics, default)
+  -- TODO(lewis6991): Document LSP protocol types
+  ty = ty:gsub('vim%.lsp%.protocol%.Method.[%w.]+', 'string')
+
   if generics then
     ty = replace_generics(ty, generics)
   end