Commands: add LspInfo

2 files changed, 205 insertions, 0 deletions

diff --git a/lua/lspconfig.lua b/lua/lspconfig.lua
index 9b9dbcf4..d8444160 100644
--- a/lua/lspconfig.lua
+++ b/lua/lspconfig.lua
@@ -1,4 +1,5 @@
 local configs = require 'lspconfig/configs'
+local lspui = require 'lspconfig/_lspui'
 
 local M = {
   util = require 'lspconfig/util';
@@ -18,6 +19,103 @@ end
 -- script in scriptnames to be executed is lspconfig.
 function M._root._setup()
   M._root.commands = {
+    LspInfo = {
+      function()
+        -- These options need to be cached before switching to the floating
+        -- buffer.
+        local buf_clients = vim.lsp.buf_get_clients()
+        local clients = vim.lsp.get_active_clients()
+        local buffer_filetype = vim.bo.filetype
+        local buffer_dir = vim.fn.expand('%:p:h')
+
+        local win_info = lspui.percentage_range_window(0.8, 0.7)
+        local bufnr, win_id = win_info.bufnr, win_info.win_id
+
+        local buf_lines = {}
+        local header = {
+          "Available servers:",
+          "\t"..table.concat(vim.tbl_keys(configs), ', '),
+          "",
+          "Clients attached to this buffer: "..tostring(#buf_clients)
+        }
+        vim.list_extend(buf_lines, header)
+
+        for _, client in ipairs(buf_clients) do
+          local client_info = {
+            "",
+            "Client: "..tostring(client.id),
+            "\tname: "..client.name,
+            "\troot: "..client.workspaceFolders[1].name,
+            "\tfiletypes: "..table.concat(client.config.filetypes, ', '),
+            "\tcmd: "..table.concat(client.config.cmd, ', '),
+          }
+           vim.list_extend(buf_lines, client_info)
+        end
+
+        local active_section_header = {
+          "",
+          "Total active clients: "..tostring(#clients),
+        }
+        vim.list_extend(buf_lines, active_section_header)
+        for _, client in ipairs(clients) do
+          local client_info = {
+            "",
+            "Client: "..tostring(client.id),
+            "\tname: "..client.name,
+            "\troot: "..client.workspaceFolders[1].name,
+            "\tfiletypes: "..table.concat(client.config.filetypes, ', '),
+            "\tcmd: "..table.concat(client.config.cmd, ', '),
+          }
+           vim.list_extend(buf_lines, client_info)
+        end
+        local matching_config_header = {
+          "",
+          "Clients that match the current buffer filetype:",
+        }
+        local cmd_not_found_msg = "False. Please check your path and ensure the server is installed"
+        vim.list_extend(buf_lines, matching_config_header)
+        for _, config in pairs(configs) do
+          --TODO(mjlbach): This is why the command is slow.
+          -- We should change config initialization so this is cached (generally)
+          local config_table = config.make_config(buffer_dir)
+
+          local cmd_is_executable, cmd
+          if config_table.cmd then
+            cmd = table.concat(config_table.cmd, " ")
+            if vim.fn.executable(config_table.cmd[1]) == 1 then
+              cmd_is_executable = "True"
+            else
+              cmd_is_executable = cmd_not_found_msg
+            end
+          else
+            cmd = "cmd not defined"
+            cmd_is_executable = cmd
+          end
+
+          for _, filetype_match in ipairs(config_table.filetypes) do
+            if buffer_filetype == filetype_match then
+              local matching_config_info = {
+                "",
+                "Config: "..config.name,
+                "\tcmd: "..cmd,
+                "\tcmd is executable: ".. cmd_is_executable,
+                "\tidentified root: "..(config_table.root_dir or "None"),
+                "\tcustom handlers: "..table.concat(vim.tbl_keys(config_table.handlers), ", "),
+              }
+             vim.list_extend(buf_lines, matching_config_info)
+            end
+          end
+        end
+        buf_lines = vim.lsp.util._trim_and_pad(buf_lines, { pad_left = 2, pad_top = 1})
+        vim.api.nvim_buf_set_lines(bufnr, 0, -1, true, buf_lines )
+        vim.fn.matchadd("Title", table.concat(vim.tbl_keys(configs), '\\|'))
+        vim.fn.matchadd("Error", "cmd not defined\\|"..cmd_not_found_msg)
+        vim.api.nvim_buf_set_keymap(bufnr, 'n', '<esc>', '<cmd>bd<CR>', { noremap = true})
+        vim.lsp.util.close_preview_autocmd({"BufHidden", "BufLeave"}, win_id)
+      end;
+      "-nargs=?";
+      description = '`:LspInfo` Displays info on currently configured and currently active servers';
+    };
     LspInstall = {
       function()
         print("deprecated, see https://github.com/neovim/neovim/wiki/Following-HEAD")
diff --git a/lua/lspconfig/_lspui.lua b/lua/lspconfig/_lspui.lua
new file mode 100644
index 00000000..609a4c49
--- /dev/null
+++ b/lua/lspconfig/_lspui.lua
@@ -0,0 +1,107 @@
+-- The following is extracted and modified from plenary.vnim by
+-- TJ Devries. It is not a stable API, and is expected to change
+--
+local function apply_defaults(original, defaults)
+  if original == nil then
+    original = {}
+  end
+
+  original = vim.deepcopy(original)
+
+  for k, v in pairs(defaults) do
+    if original[k] == nil then
+      original[k] = v
+    end
+  end
+
+  return original
+end
+
+local win_float = {}
+
+win_float.default_options = {
+  winblend = 15,
+  percentage = 0.9,
+}
+
+function win_float.default_opts(options)
+  options = apply_defaults(options, win_float.default_options)
+
+  local width = math.floor(vim.o.columns * options.percentage)
+  local height = math.floor(vim.o.lines * options.percentage)
+
+  local top = math.floor(((vim.o.lines - height) / 2) - 1)
+  local left = math.floor((vim.o.columns - width) / 2)
+
+  local opts = {
+    relative = 'editor',
+    row      = top,
+    col      = left,
+    width    = width,
+    height   = height,
+    style    = 'minimal'
+  }
+
+  return opts
+end
+--- Create window that takes up certain percentags of the current screen.
+---
+--- Works regardless of current buffers, tabs, splits, etc.
+--@param col_range number | Table:
+--                  If number, then center the window taking up this percentage of the screen.
+--                  If table, first index should be start, second_index should be end
+--@param row_range number | Table:
+--                  If number, then center the window taking up this percentage of the screen.
+--                  If table, first index should be start, second_index should be end
+function win_float.percentage_range_window(col_range, row_range, options)
+  options = apply_defaults(options, win_float.default_options)
+
+  local win_opts = win_float.default_opts(options)
+  win_opts.relative = "editor"
+
+  local height_percentage, row_start_percentage
+  if type(row_range) == 'number' then
+    assert(row_range <= 1)
+    assert(row_range > 0)
+    height_percentage = row_range
+    row_start_percentage = (1 - height_percentage) / 2
+  elseif type(row_range) == 'table' then
+    height_percentage = row_range[2] - row_range[1]
+    row_start_percentage = row_range[1]
+  else
+    error(string.format("Invalid type for 'row_range': %p", row_range))
+  end
+
+  win_opts.height = math.ceil(vim.o.lines * height_percentage)
+  win_opts.row = math.ceil(vim.o.lines *  row_start_percentage)
+
+  local width_percentage, col_start_percentage
+  if type(col_range) == 'number' then
+    assert(col_range <= 1)
+    assert(col_range > 0)
+    width_percentage = col_range
+    col_start_percentage = (1 - width_percentage) / 2
+  elseif type(col_range) == 'table' then
+    width_percentage = col_range[2] - col_range[1]
+    col_start_percentage = col_range[1]
+  else
+    error(string.format("Invalid type for 'col_range': %p", col_range))
+  end
+
+  win_opts.col = math.floor(vim.o.columns * col_start_percentage)
+  win_opts.width = math.floor(vim.o.columns * width_percentage)
+
+  local bufnr = options.bufnr or vim.fn.nvim_create_buf(false, true)
+  local win_id = vim.fn.nvim_open_win(bufnr, true, win_opts)
+  vim.api.nvim_win_set_buf(win_id, bufnr)
+
+  vim.cmd('setlocal nocursorcolumn')
+  vim.fn.nvim_win_set_option(win_id, 'winblend', options.winblend)
+
+  return {
+    bufnr = bufnr,
+    win_id = win_id,
+  }
+end
+
+return win_float