feat(ex): add `:log` command

3 files changed, 81 insertions, 13 deletions

diff --git a/runtime/lua/vim/_core/ex_cmd.lua b/runtime/lua/vim/_core/ex_cmd.lua
index a46892abaa..a9a7a588ed 100644
--- a/runtime/lua/vim/_core/ex_cmd.lua
+++ b/runtime/lua/vim/_core/ex_cmd.lua
@@ -1,5 +1,6 @@
 local api = vim.api
-local lsp = vim.lsp
+local fs = vim.fs
+local util = require('vim._core.util')
 
 local M = {}
 
@@ -11,7 +12,7 @@ end
 --- @return string[]
 local function get_client_names()
   return vim
-    .iter(lsp.get_clients())
+    .iter(vim.lsp.get_clients())
     :map(function(client)
       return client.name
     end)
@@ -24,7 +25,7 @@ end
 local function filtered_config_names(filter)
   return function()
     return vim
-      .iter(lsp.get_configs(filter))
+      .iter(vim.lsp.get_configs(filter))
       :map(function(config)
         return config.name
       end)
@@ -43,8 +44,8 @@ local complete_args = {
 --- @param enable? boolean
 local function checked_enable(names, enable)
   for _, name in ipairs(names) do
-    if name:find('*') == nil and lsp.config[name] ~= nil then
-      lsp.enable(name, enable)
+    if name:find('*') == nil and vim.lsp.config[name] ~= nil then
+      vim.lsp.enable(name, enable)
     else
       echo_err(("No client config named '%s'"):format(name))
     end
@@ -56,7 +57,7 @@ local function ex_lsp_enable(config_names)
   -- Default to enabling all clients matching the filetype of the current buffer.
   if #config_names == 0 then
     local filetype = vim.bo.filetype
-    for _, config in ipairs(lsp.get_configs()) do
+    for _, config in ipairs(vim.lsp.get_configs()) do
       local filetypes = config.filetypes
       if filetypes == nil or vim.list_contains(filetypes, filetype) then
         table.insert(config_names, config.name)
@@ -80,12 +81,12 @@ local function ex_lsp_disable(config_names)
   -- Default to disabling all clients attached to the current buffer.
   if #config_names == 0 then
     config_names = vim
-      .iter(lsp.get_clients { bufnr = api.nvim_get_current_buf() })
+      .iter(vim.lsp.get_clients { bufnr = api.nvim_get_current_buf() })
       :map(function(client)
         return client.name
       end)
       :filter(function(name)
-        return lsp.config[name] ~= nil
+        return vim.lsp.config[name] ~= nil
       end)
       :totable()
     if #config_names == 0 then
@@ -102,7 +103,7 @@ end
 local function get_clients_from_names(client_names)
   -- Default to all active clients attached to the current buffer.
   if #client_names == 0 then
-    local clients = lsp.get_clients { bufnr = api.nvim_get_current_buf() }
+    local clients = vim.lsp.get_clients { bufnr = api.nvim_get_current_buf() }
     if #clients == 0 then
       echo_err('No clients attached to current buffer')
     end
@@ -111,7 +112,7 @@ local function get_clients_from_names(client_names)
     return vim
       .iter(client_names)
       :map(function(name)
-        local clients = lsp.get_clients { name = name }
+        local clients = vim.lsp.get_clients { name = name }
         if #clients == 0 then
           echo_err(("No active clients named '%s'"):format(name))
         end
@@ -186,4 +187,45 @@ function M.lsp_complete(line)
   end
 end
 
+--- @type string
+--- @diagnostic disable-next-line: assign-type-mismatch
+local log_dir = vim.fn.stdpath('log')
+
+--- Implements command: `:log {file}`.
+--- @param filename string
+--- @param mods string
+M.ex_log = function(filename, mods)
+  if filename == '' then
+    util.wrapped_edit(log_dir, mods)
+  else
+    local path --- @type string
+    -- Special case for NVIM_LOG_FILE
+    local nvim_log_file = vim.env.NVIM_LOG_FILE --- @type string
+    if filename == 'nvim' and nvim_log_file and nvim_log_file ~= '' then
+      path = nvim_log_file
+    else
+      path = fs.joinpath(log_dir, filename .. '.log')
+    end
+    if not vim.uv.fs_stat(path) then
+      echo_err(("No such log file: '%s'"):format(path))
+      return
+    end
+    util.wrapped_edit(path, mods)
+    vim.cmd.normal { 'G', bang = true }
+  end
+end
+
+--- Completion logic for `:log` command
+--- @return string[] list of completions
+function M.log_complete()
+  local names = { 'nvim' } --- @type string[]
+  for file, type in vim.fs.dir(log_dir, { depth = math.huge }) do
+    local name, matches = file:gsub('%.log$', '')
+    if matches ~= 0 and type == 'file' and name ~= 'nvim' then
+      names[#names + 1] = name
+    end
+  end
+  return names
+end
+
 return M
diff --git a/runtime/lua/vim/_core/util.lua b/runtime/lua/vim/_core/util.lua
index b2d5f9ef0f..973cf1da2d 100644
--- a/runtime/lua/vim/_core/util.lua
+++ b/runtime/lua/vim/_core/util.lua
@@ -22,6 +22,17 @@ function M.space_below()
   add_blank()
 end
 
+--- Gets a buffer by name
+--- @param name string
+--- @return integer?
+function M.get_buf_by_name(name)
+  for _, buf in ipairs(vim.api.nvim_list_bufs()) do
+    if vim.api.nvim_buf_get_name(buf) == name then
+      return buf
+    end
+  end
+end
+
 --- Edit a file in a specific window
 --- @param winnr number
 --- @param file string
@@ -49,6 +60,23 @@ M.edit_in = function(winnr, file)
   end)
 end
 
+--- :edit, but it respects commands like :hor, :vert, :tab, etc.
+--- @param file string
+--- @param mods_str string
+function M.wrapped_edit(file, mods_str)
+  local cmdline = table.concat({ mods_str, 'edit' }, ' ')
+  local mods = vim.api.nvim_parse_cmd(cmdline, {}).mods
+  --- @diagnostic disable-next-line: need-check-nil
+  if mods.tab > 0 or mods.split ~= '' or mods.horizontal or mods.vertical then
+    local buf = M.get_buf_by_name(file)
+    if buf == nil then
+      buf = vim.api.nvim_create_buf(true, false)
+    end
+    vim.cmd.sbuffer { buf, mods = mods }
+  end
+  vim.cmd.edit { file }
+end
+
 --- Read a chunk of data from a file
 --- @param file string
 --- @param size number
diff --git a/runtime/lua/vim/lsp/log.lua b/runtime/lua/vim/lsp/log.lua
index beab643191..34cec30970 100644
--- a/runtime/lua/vim/lsp/log.lua
+++ b/runtime/lua/vim/lsp/log.lua
@@ -10,11 +10,9 @@
 ---
 --- Then try to run the language server, and open the log with:
 --- ```vim
---- :lua vim.cmd('tabnew ' .. vim.lsp.log.get_filename())
+--- :log lsp
 --- ```
 ---
---- (Or use `:LspLog` if you have nvim-lspconfig installed.)
----
 --- Note:
 --- - Remember to DISABLE verbose logging ("debug" or "trace" level), else you may encounter
 ---   performance issues.