fix: use remote server for executing commands

Author: smjonas

README.md

@@ -1,30 +1,32 @@
 # live-command.nvim
-![version](https://img.shields.io/badge/version-1.2.1-brightgreen)
+![version](https://img.shields.io/badge/version-1.3.0-brightgreen)
 
 Text editing in Neovim with immediate visual feedback: view the effects of any command on your buffer contents live. Preview macros, the `:norm` command & more!
 
 ![live-command.nvim demo video](https://user-images.githubusercontent.com/40792180/235201812-adc95327-65cc-4ae4-8c2e-804853dd0c02.gif)
 <p><sub>Theme: <a href="https://github.com/folke/tokyonight.nvim">tokyonight.nvim</a></sub></p>
 
 ## :sparkles: Motivation and Features
-In version 0.8, Neovim has introduced the `command-preview` feature.
-Contrary to what "command preview" suggests, previewing any given
-command does not work out of the box: you need to manually update the buffer text and set
-highlights *for every command*.
+In Neovim version 0.8, the `command-preview` feature has been introduced.
+Despite its name, it does not enable automatic previewing of any command.
+Instead, users must manually update the buffer text and set highlights *for each command*.
 
-This plugin tries to change that: it provides a **simple API for creating previewable commands**
-in Neovim. Just specify the command you want to run and live-command will do all the
-work for you. This includes viewing **individual insertions, changes and deletions** as you
-type.
+This plugin aims to address this issue by offering a **simple API for creating previewable commands**
+in Neovim. Simply provide the command you want to preview and live-command will do all the
+work for you. This includes viewing **individual insertions, changes and deletions** as you type.
+
+After the most recent update, live-command now spawns a separate Neovim instance to execute commands.
+This avoids many issues encountered when running the command directly in the current Neovim instance
+([#6](https://github.com/smjonas/live-command.nvim/issues/6), [#16](https://github.com/smjonas/live-command.nvim/issues/16), [#24](https://github.com/smjonas/live-command.nvim/issues/24), [#28](https://github.com/smjonas/live-command.nvim/issues/28)).
 
 ## Requirements
 Neovim 0.8+
 
 ## :rocket: Getting started
 Install using your favorite package manager and call the setup function with a table of
-commands to create. Here is an example that creates a previewable `:Norm` command:
+commands to create. Here is an example for `lazy.nvim` that creates a previewable `:Norm` command:
 ```lua
-use {
+{
   "smjonas/live-command.nvim",
   -- live-command supports semantic versioning via tags
   -- tag = "1.*",
@@ -84,7 +86,6 @@ require("live-command").setup {
       change = "DiffChange",
     },
   },
-  debug = false,
 }
 ```
 
@@ -119,15 +120,6 @@ deletion edits will not be undone which is otherwise done to make the text chang
 
 ---
 
-`debug: boolean`
-
-Default: `false`
-
-If `true`, more stuff (not only errors) will be logged. After previewing a command,
-you can view the log by running `:LiveCommandLog`.
-
----
-
 Like this project? Give it a :star: to show your support!
 
 Also consider checking out my other plugin [inc-rename.nvim](https://github.com/smjonas/inc-rename.nvim),

lua/live-command/init.lua

@@ -10,22 +10,22 @@ M.defaults = {
   },
 }
 
+local api = vim.api
+
+---@type Logger
+local logger
+
+---@class Remote
+local remote
+
+---@type number?
+local chan_id
+
+local cursor_row, cursor_col
 local should_cache_lines = true
 local cached_lines
 local prev_lazyredraw
 
-local logs = {}
-local function log(msg, level)
-  level = level or "TRACE"
-  if M.debug or level ~= "TRACE" then
-    msg = type(msg) == "function" and msg() or msg
-    logs[level] = logs[level] or {}
-    for _, line in ipairs(vim.split(msg .. "\n", "\n")) do
-      table.insert(logs[level], line)
-    end
-  end
-end
-
 -- Inserts str_2 into str_1 at the given position.
 local function string_insert(str_1, str_2, pos)
   return str_1:sub(1, pos - 1) .. str_2 .. str_1:sub(pos)
@@ -47,7 +47,7 @@ local function add_inline_highlights(line, cached_lns, updated_lines, undo_delet
   local line_a = splice(cached_lns[line])
   local line_b = splice(updated_lines[line])
   local line_diff = vim.diff(line_a, line_b, { result_type = "indices" })
-  log(function()
+  logger.trace(function()
     return ("Changed lines (line %d):\nOriginal: '%s' (len=%d)\nUpdated:  '%s' (len=%d)\n\nInline hunks: %s"):format(
       line,
       cached_lns[line],
@@ -85,6 +85,7 @@ local function add_inline_highlights(line, cached_lns, updated_lines, undo_delet
       -- Observation: when changing "line" to "tes", there should not be an offset (-2)
       -- after changing "lin" to "t" (because we are not modifying the line)
       highlight.column = highlight.column + col_offset
+      highlight.hunk = nil
       table.insert(highlights, highlight)
 
       if defer then
@@ -104,10 +105,10 @@ local function get_diff_highlights(cached_lns, updated_lines, line_range, opts)
   local hunks = vim.diff(table.concat(cached_lns, "\n"), table.concat(updated_lines, "\n"), {
     result_type = "indices",
   })
-  log(("Visible line range: %d-%d"):format(line_range[1], line_range[2]))
+  logger.trace(("Visible line range: %d-%d"):format(line_range[1], line_range[2]))
 
   for i, hunk in ipairs(hunks) do
-    log(function()
+    logger.trace(function()
       return ("Hunk %d/%d: %s"):format(i, #hunks, vim.inspect(hunk))
     end)
 
@@ -123,7 +124,7 @@ local function get_diff_highlights(cached_lns, updated_lines, line_range, opts)
         end_line = start_line + (count_a - count_b) - 1
       end
 
-      log(function()
+      logger.trace(function()
         return ("Lines %d-%d:\nOriginal: %s\nUpdated: %s"):format(
           start_line,
           end_line,
@@ -176,29 +177,35 @@ end
 -- Expose functions to tests
 M._preview_across_lines = get_diff_highlights
 
-local function run_buf_cmd(buf, cmd)
-  vim.api.nvim_buf_call(buf, function()
-    log(function()
-      return ("Previewing command: %s (current line = %d)"):format(cmd, vim.api.nvim_win_get_cursor(0)[1])
-    end)
-    vim.cmd(cmd)
+---@param cmd string
+local function run_cmd(cmd)
+  if not chan_id then
+    logger.trace("run_cmd: skipped as chan_id is not set")
+    return
+  end
+
+  local cursor_pos = api.nvim_win_get_cursor(0)
+  cursor_row, cursor_col = cursor_pos[1], cursor_pos[2]
+
+  logger.trace(function()
+    return ("Previewing command: %s (l=%d,c=%d)"):format(cmd, cursor_row, cursor_col)
   end)
+  return remote.run_cmd(chan_id, cmd, cursor_row, cursor_col)
 end
 
 -- Called when the user is still typing the command or the command arguments
 local function command_preview(opts, preview_ns, preview_buf)
   -- Any errors that occur in the preview function are not directly shown to the user but stored in vim.v.errmsg.
   -- Related: https://github.com/neovim/neovim/issues/18910.
   vim.v.errmsg = ""
-  logs = {}
   local args = opts.cmd_args
   local command = opts.command
 
-  local bufnr = vim.api.nvim_get_current_buf()
+  local bufnr = api.nvim_get_current_buf()
   if should_cache_lines then
     prev_lazyredraw = vim.o.lazyredraw
     vim.o.lazyredraw = true
-    cached_lines = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
+    cached_lines = api.nvim_buf_get_lines(bufnr, 0, -1, false)
     should_cache_lines = false
   end
 
@@ -207,10 +214,11 @@ local function command_preview(opts, preview_ns, preview_buf)
   local prev_errmsg = vim.v.errmsg
   local visible_line_range = { vim.fn.line("w0"), vim.fn.line("w$") }
 
+  local updated_lines
   if opts.line1 == opts.line2 then
-    run_buf_cmd(bufnr, ("%s %s"):format(command.cmd, args))
+    updated_lines = run_cmd(("%s %s"):format(command.cmd, args))
   else
-    run_buf_cmd(bufnr, ("%d,%d%s %s"):format(opts.line1, opts.line2, command.cmd, args))
+    updated_lines = run_cmd(("%d,%d%s %s"):format(opts.line1, opts.line2, command.cmd, args))
   end
 
   vim.v.errmsg = prev_errmsg
@@ -220,20 +228,19 @@ local function command_preview(opts, preview_ns, preview_buf)
     math.max(visible_line_range[2], vim.fn.line("w$")),
   }
 
-  local updated_lines = vim.api.nvim_buf_get_lines(bufnr, 0, -1, false)
   local set_lines = function(lines)
     -- TODO: is this worth optimizing?
-    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
+    api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
     if preview_buf then
-      vim.api.nvim_buf_set_lines(preview_buf, 0, -1, false, lines)
+      api.nvim_buf_set_lines(preview_buf, 0, -1, false, lines)
     end
   end
 
   if not opts.line1 or not command.enable_highlighting then
     set_lines(updated_lines)
     -- This should not happen
     if not opts.line1 then
-      log("No line1 range provided", "ERROR")
+      logger.error("No line1 range provided")
     end
     return 2
   end
@@ -247,15 +254,15 @@ local function command_preview(opts, preview_ns, preview_buf)
     undo_deletions = command.hl_groups["deletion"] ~= false,
     inline_highlighting = command.inline_highlighting,
   })
-  log(function()
+  logger.trace(function()
     return "Highlights: " .. vim.inspect(highlights)
   end)
 
   set_lines(updated_lines)
   for _, hl in ipairs(highlights) do
     local hl_group = command.hl_groups[hl.kind]
     if hl_group ~= false then
-      vim.api.nvim_buf_add_highlight(
+      api.nvim_buf_add_highlight(
         bufnr,
         preview_ns,
         hl_group,
@@ -272,20 +279,20 @@ local function restore_buffer_state()
   vim.o.lazyredraw = prev_lazyredraw
   should_cache_lines = true
   if vim.v.errmsg ~= "" then
-    log(("An error occurred in the preview function:\n%s"):format(vim.inspect(vim.v.errmsg)), "ERROR")
+    logger.error(("An error occurred in the preview function:\n%s"):format(vim.inspect(vim.v.errmsg)))
   end
 end
 
 local function execute_command(command)
-  log("Executing command: " .. command)
+  logger.trace("Executing command: " .. command)
   vim.cmd(command)
   restore_buffer_state()
 end
 
 local create_user_commands = function(commands)
   for name, command in pairs(commands) do
     local args, range
-    vim.api.nvim_create_user_command(name, function(opts)
+    api.nvim_create_user_command(name, function(opts)
       local range_string = range and range
         or (
           opts.range == 2 and ("%s,%s"):format(opts.line1, opts.line2)
@@ -341,7 +348,47 @@ local validate_config = function(config)
   end
 end
 
+local create_autocmds = function()
+  local id = api.nvim_create_augroup("command_preview.nvim", { clear = true })
+
+  api.nvim_create_autocmd("CmdlineEnter", {
+    group = id,
+    callback = function()
+      remote.sync(chan_id)
+    end,
+  })
+
+  -- We need to be able to tell when the command was cancelled so the buffer lines are refetched next time
+  api.nvim_create_autocmd("CmdLineLeave", {
+    group = id,
+    -- Schedule wrap to run after a potential command execution
+    callback = vim.schedule_wrap(function()
+      restore_buffer_state()
+    end),
+  })
+
+  api.nvim_create_autocmd("VimLeavePre", {
+    group = id,
+    callback = function()
+      if chan_id then
+        vim.fn.chanclose(chan_id)
+      end
+    end,
+  })
+
+  -- Setting dirty = true on FocusGained is important with multiple Nvim instances
+  api.nvim_create_autocmd({ "TextChanged", "TextChangedI", "BufEnter", "FocusGained" }, {
+    group = id,
+    callback = remote.on_buffer_updated,
+  })
+end
+
 M.setup = function(user_config)
+  -- Avoid an infinite loop when invoked from a child process
+  if vim.env.LIVECOMMAND_NVIM_SERVER == "1" then
+    return
+  end
+
   if vim.fn.has("nvim-0.8.0") ~= 1 then
     vim.notify(
       "[live-command] This plugin requires at least Neovim 0.8. Please upgrade your Neovim version.",
@@ -353,28 +400,21 @@ M.setup = function(user_config)
   local config = vim.tbl_deep_extend("force", M.defaults, user_config or {})
   validate_config(config)
   create_user_commands(config.commands)
+  logger = require("live-command.logger")
+  remote = require("live-command.remote")
 
-  local id = vim.api.nvim_create_augroup("command_preview.nvim", { clear = true })
-  -- We need to be able to tell when the command was cancelled so the buffer lines are refetched next time.
-  vim.api.nvim_create_autocmd({ "CmdLineLeave" }, {
-    group = id,
-    -- Schedule wrap to run after a potential command execution
-    callback = vim.schedule_wrap(function()
-      restore_buffer_state()
-    end),
-  })
-
-  M.debug = user_config.debug
+  remote.init_rpc(logger, function(id)
+    chan_id = id
+    logger.set_chan_id(chan_id)
+  end)
+  create_autocmds()
+end
 
-  vim.api.nvim_create_user_command("LiveCommandLog", function()
-    local msg = ("live-command log\n================\n\n%s%s"):format(
-      logs.ERROR and "[ERROR]\n" .. table.concat(logs.ERROR, "\n") .. (logs.TRACE and "\n" or "") or "",
-      logs.TRACE and "[TRACE]\n" .. table.concat(logs.TRACE, "\n") or ""
-    )
-    vim.notify(msg)
-  end, { nargs = 0 })
+---@param logger_ Logger
+M._set_logger = function(logger_)
+  logger = logger_
 end
 
-M.version = "1.2.1"
+M.version = "1.3.0"
 
 return M