feat(lsp): add more LSP defaults (#28500)

- crn for rename
- crr for code actions
- gr for references
- <C-S> (in Insert mode) for signature help

runtime/doc/change.txt

@@ -281,6 +281,10 @@ gr{char}		Replace the virtual characters under the cursor with
 			that have a special meaning in Insert mode, such as
 			most CTRL-keys, cannot be used.
 
+							*gr-default*
+			Mapped to |vim.lsp.buf.references()| by default.
+			|default-mappings|
+
 						*digraph-arg*
 The argument for Normal mode commands like |r| and |t| is a single character.
 When 'cpo' doesn't contain the 'D' flag, this character can also be entered

runtime/doc/lsp.txt

@@ -61,47 +61,41 @@ options are not restored when the LSP client is stopped or detached.
 - |K| is mapped to |vim.lsp.buf.hover()| unless |'keywordprg'| is customized or
   a custom keymap for `K` exists.
 
+                                                  *crr* *v_crr* *crn* *i_CTRL-S*
+Some keymaps are created unconditionally when Nvim starts:
+- "crn" is mapped in Normal mode to |vim.lsp.buf.rename()|
+- "crr" is mapped in Normal and Visual mode to |vim.lsp.buf.code_action()|
+- "gr" is mapped in Normal mode to |vim.lsp.buf.references()| |gr-default|
+- CTRL-S is mapped in Insert mode to |vim.lsp.buf.signature_help()|
+
+If not wanted, these keymaps can be removed at any time using
+|vim.keymap.del()| or |:unmap|.
+
                                                         *lsp-defaults-disable*
 To override the above defaults, set or unset the options on |LspAttach|: >lua
+
     vim.api.nvim_create_autocmd('LspAttach', {
       callback = function(ev)
         vim.bo[ev.buf].formatexpr = nil
         vim.bo[ev.buf].omnifunc = nil
-        vim.keymap.del("n", "K", { buffer = ev.buf })
+        vim.keymap.del('n', 'K', { buffer = ev.buf })
       end,
     })
 
-To use other LSP features like hover, rename, etc. you can set other keymaps
+To use other LSP features, set keymaps on |LspAttach|. Not all language
-on |LspAttach|. Example: >lua
+servers provide the same capabilities. To ensure you only set keymaps if the
-    vim.api.nvim_create_autocmd('LspAttach', {
+language server supports a feature, guard keymaps behind capability checks.
-      callback = function(args)
+Example: >lua
-        vim.keymap.set('n', 'K', vim.lsp.buf.hover, { buffer = args.buf })
-      end,
-    })
 
-The most common functions are:
-
-- |vim.lsp.buf.hover()|
-- |vim.lsp.buf.format()|
-- |vim.lsp.buf.references()|
-- |vim.lsp.buf.implementation()|
-- |vim.lsp.buf.code_action()|
-
-
-Not all language servers provide the same capabilities. To ensure you only set
-keymaps if the language server supports a feature, you can guard the keymap
-calls behind capability checks:
->lua
     vim.api.nvim_create_autocmd('LspAttach', {
       callback = function(args)
         local client = vim.lsp.get_client_by_id(args.data.client_id)
-        if client.server_capabilities.hoverProvider then
+        if client.supports_method('textDocument/implementation') then
-          vim.keymap.set('n', 'K', vim.lsp.buf.hover, { buffer = args.buf })
+          vim.keymap.set('n', 'g<C-I>', vim.lsp.buf.implementation, { buffer = args.buf })
         end
       end,
     })
 <
-
 To learn what capabilities are available you can run the following command in
 a buffer with a started LSP client: >vim
 

runtime/doc/news.txt

@@ -408,6 +408,10 @@ The following changes to existing APIs or features add new behavior.
   • 'comments' includes "fb:•".
   • 'shortmess' includes the "C" flag.
   • 'grepprg' defaults to using ripgrep if available.
+  • |crn| in Normal mode maps to |vim.lsp.buf.rename()|.
+  • |crr| in Normal and Visual mode maps to |vim.lsp.buf.code_action()|.
+  • "gr" in Normal mode maps to |vim.lsp.buf.references()| |gr-default|
+  • |i_CTRL-S| in Insert mode maps to |vim.lsp.buf.signature_help()|
   • Automatic linting of treesitter query files (see |ft-query-plugin|).
     Can be disabled via: >lua
       vim.g.query_lint_on = {}
@@ -438,9 +442,10 @@ The following changes to existing APIs or features add new behavior.
 
   :call netrw#BrowseX(expand(exists("g:netrw_gx")? g:netrw_gx : '<cfile>'), netrw#CheckIfRemote())<CR>
 
-• |vim.lsp.start()| now maps |K| to use |vim.lsp.buf.hover()| if the server
+• |vim.lsp.start()| now creates the following default keymaps (assuming the
-  supports it, unless |'keywordprg'| was customized before calling
+  server supports the feature):
-  |vim.lsp.start()|.
+  - |K| in Normal mode maps to |vim.lsp.buf.hover()|, unless |'keywordprg'|
+    was customized before calling |vim.lsp.start()|.
 
 • Terminal buffers started with no arguments (and use 'shell') close
   automatically if the job exited without error, eliminating the (often

runtime/doc/vim_diff.txt

@@ -137,6 +137,10 @@ of these in your config by simply removing the mapping, e.g. ":unmap Y".
 - * |v_star-default|
 - gc |gc-default| |v_gc-default| |o_gc-default|
 - gcc |gcc-default|
+- |crn|
+- |crr|
+- gr |gr-default|
+- <C-S> |i_CTRL-S|
 - Nvim LSP client defaults |lsp-defaults|
   - K |K-lsp-default|
 

runtime/lua/vim/_defaults.lua

@@ -144,6 +144,31 @@ do
     end
     vim.keymap.set({ 'o' }, 'gc', textobject_rhs, { desc = 'Comment textobject' })
   end
+
+  --- Default maps for LSP functions.
+  ---
+  --- These are mapped unconditionally to avoid confusion. If no server is attached, or if a server
+  --- does not support a capability, an error message is displayed rather than exhibiting different
+  --- behavior.
+  ---
+  --- See |gr-default|, |crn|, |crr|, |i_CTRL-S|.
+  do
+    vim.keymap.set('n', 'crn', function()
+      vim.lsp.buf.rename()
+    end, { desc = 'vim.lsp.buf.rename()' })
+
+    vim.keymap.set({ 'n', 'v' }, 'crr', function()
+      vim.lsp.buf.code_action()
+    end, { desc = 'vim.lsp.buf.code_action()' })
+
+    vim.keymap.set('n', 'gr', function()
+      vim.lsp.buf.references()
+    end, { desc = 'vim.lsp.buf.references()' })
+
+    vim.keymap.set('i', '<C-S>', function()
+      vim.lsp.buf.signature_help()
+    end, { desc = 'vim.lsp.buf.signature_help()' })
+  end
 end
 
 --- Default menus
@@ -243,7 +268,6 @@ do
       vim.notify(('W325: Ignoring swapfile from Nvim process %d'):format(info.pid))
     end,
   })
-end
 
   -- Only do the following when the TUI is attached
   local tty = nil
@@ -499,7 +523,10 @@ if tty then
       end
     end
   end
+end
 
+--- Default options
+do
   --- Default 'grepprg' to ripgrep if available.
   if vim.fn.executable('rg') == 1 then
     -- Match :grep default, otherwise rg searches cwd by default
@@ -507,3 +534,4 @@ if vim.fn.executable('rg') == 1 then
     vim.o.grepprg = 'rg --vimgrep -uuu $* ' .. (vim.fn.has('unix') == 1 and '/dev/null' or 'nul')
     vim.o.grepformat = '%f:%l:%c:%m'
   end
+end

runtime/lua/vim/lsp.lua

@@ -348,7 +348,7 @@ function lsp._set_defaults(client, bufnr)
       and is_empty_or_default(bufnr, 'keywordprg')
       and vim.fn.maparg('K', 'n', false, false) == ''
     then
-      vim.keymap.set('n', 'K', vim.lsp.buf.hover, { buffer = bufnr })
+      vim.keymap.set('n', 'K', vim.lsp.buf.hover, { buffer = bufnr, desc = 'vim.lsp.buf.hover()' })
     end
   end)
   if client.supports_method(ms.textDocument_diagnostic) then