feat: Live previews (peek editor)

Disabled by default, but if this feature turns out to be useful and
stable, it will replace the old preview window.

CHANGELOG.md

@@ -79,6 +79,10 @@
   ([#37](https://github.com/hedyhli/outline.nvim/issues/37))
 - Added `get_symbol` and `get_breadcrumb` functions (useful in
   statusline/winbar) ([#24](https://github.com/hedyhli/outline.nvim/issues/24))
+- New "Live Preview" feature which allows editing in the preview buffer. This
+  allows navigating some symbol away from cursor location and make quick edits in
+  the other position using the preview window. This feature is currently
+  experimental and opt-in. Enable with `preview_window.live = true`
 
 ### Fixes
 
@@ -116,6 +120,9 @@
 - Follow cursor algorithm significantly improved
 - Highlight hovered item and initial opening of outline has been rewritten and
   performance improved
+- Revamped various provider-related modules such as rename/code-actions/hover
+  to delegate the task to specific providers
+- Revamped the preview module for better per-tab outline support and more features
 
 ### Others
 

README.md

@@ -309,6 +309,9 @@ Pass a table to the setup call with your configuration options.
     winhl = 'NormalFloat:',
     -- Pseudo-transparency of the preview window, see ':h winblend'
     winblend = 0
+    -- Experimental feature that let's you edit the source content live
+    -- in the preview window. Like VS Code's "peek editor".
+    live = false
   },
 
   -- These keymaps can be a string or a table for multiple keys.
@@ -1036,6 +1039,27 @@ symbols = {
 
 <div align=center><img width="500" alt="outline with disabled icon for String" src="https://github.com/hedyhli/outline.nvim/assets/50042066/26d258c6-9530-43d4-b88b-963304e3bf2d"></div>
 
+### Live, editable previews
+
+Press `K` to open the preview, press `K` again to focus on the preview window
+to make any quick edits, similar to VS Code's reference window "peek editor".
+
+Then use `:q` to close the window, and continue browsing the outline.
+
+```lua
+preview_window = {
+  live = true,
+}
+```
+
+Note that this feature is experimental and may be unstable.
+
+https://github.com/hedyhli/outline.nvim/assets/50042066/183fc5f9-b369-41e2-a831-a4185704d76d
+
+Auto-preview with the feature is also supported, set `auto_preview = true` and
+press `K` to focus on the auto-opened preview window. `:q` to quit the window.
+
+
 <!-- panvimdoc-ignore-start -->
 
 ---

lua/outline/config.lua

@@ -48,6 +48,7 @@ M.defaults = {
     center_on_jump = true,
   },
   preview_window = {
+    live = false,
     auto_preview = false,
     width = 50,
     min_width = 50,

lua/outline/init.lua

@@ -24,9 +24,13 @@ local function setup_global_autocmd()
     pattern = '*',
     callback = function()
       local s = M._get_sidebar()
+      local w = vim.api.nvim_get_current_win()
       if s and s.preview then
+        -- Don't close preview when entering preview!
+        if not s.preview.win or s.preview.win ~= w then
           s.preview:close()
         end
+      end
     end,
   })
   vim.api.nvim_create_autocmd('TabClosed', {

lua/outline/preview.lua

@@ -1,7 +1,8 @@
-local cfg = require('outline.config')
+-- A floating window to preview the location of a symbol from the outline.
-local providers = require('outline.providers')
+-- Classical preview reads entire lines into a new buffer for preview. Live
-
+-- preview sets the buffer of floating window to the code buffer, which allows
-local conf
+-- focusing by pressing the preview keymap again, to edit the buffer at that
+-- position.
 
 ---@class outline.Preview
 local Preview = {}
@@ -9,77 +10,53 @@ local Preview = {}
 ---@class outline.Preview
 ---@field buf integer
 ---@field win integer
----@field width integer
 ---@field height integer
+---@field width integer
 ---@field outline_height integer
 ---@field s outline.Sidebar
+---@field conf table
 
----@param s outline.Sidebar
+---@class outline.LivePreview
-function Preview:new(s)
+local LivePreview = {}
-  -- Config must have been setup when calling Preview:new
+
-  conf = cfg.o.preview_window
+---@class outline.LivePreview
+---@field win integer
+---@field codewin integer
+---@field codebuf integer
+---@field height integer
+---@field width integer
+---@field outline_height integer
+---@field s outline.Sidebar
+---@field last_node outline.FlatSymbol
+---@field initial_cursorline boolean
+---@field conf table
+
+---@param conf table
+function Preview:new(conf)
+  if conf.live == true then
     return setmetatable({
+      conf = conf,
+      win = nil,
+      width = nil,
+      height = nil,
+    }, { __index = LivePreview })
+  else
+    return setmetatable({
+      conf = conf,
       buf = nil,
       win = nil,
-    s = s,
       width = nil,
       height = nil,
     }, { __index = Preview })
   end
-
----Creates new preview window and sets the content. Calls setup and set_lines.
-function Preview:create()
-  self.buf = vim.api.nvim_create_buf(false, true)
-  vim.api.nvim_buf_attach(self.buf, false, {
-    on_detach = function()
-      self.buf = nil
-      self.win = nil
-    end,
-  })
-  -- FIXME: Re-calculate dimensions on update-preview, in case outline window
-  -- was resized between last preview and next preview?
-  self.outline_height = vim.api.nvim_win_get_height(self.s.view.win)
-  self.width = conf.width
-  self.height = math.max(math.ceil(self.outline_height / 2), conf.min_height)
-  self.win = vim.api.nvim_open_win(self.buf, false, {
-    relative = 'editor',
-    height = self.height,
-    width = self.width,
-    bufpos = { 0, 0 },
-    col = self:calc_col(),
-    row = self:calc_row(),
-    border = conf.border,
-  })
-  self:setup()
-  self:set_lines()
-end
-
----Set up highlights, window, and buffer options
-function Preview:setup()
-  vim.api.nvim_win_set_option(self.win, 'winhl', conf.winhl)
-  vim.api.nvim_win_set_option(self.win, 'winblend', conf.winblend)
-
-  local code_buf = self.s.code.buf
-  local ft = vim.api.nvim_buf_get_option(code_buf, 'filetype')
-  vim.api.nvim_buf_set_option(self.buf, 'syntax', ft)
-
-  local ts_highlight_fn = vim.treesitter.start
-  if not _G._outline_nvim_has[8] then
-    local ok, ts_highlight = pcall(require, 'nvim-treesitter.highlight')
-    if ok then
-      ts_highlight_fn = ts_highlight.attach
-    end
-  end
-  pcall(ts_highlight_fn, self.buf, ft)
-
-  vim.api.nvim_buf_set_option(self.buf, 'bufhidden', 'delete')
-  vim.api.nvim_win_set_option(self.win, 'cursorline', true)
-  vim.api.nvim_buf_set_option(self.buf, 'modifiable', false)
 end
 
 ---Get the correct column to place the floating window based on relative
 ---positions of the outline and the code window.
-function Preview:calc_col()
+---@param self outline.Preview|outline.LivePreview
+local function calc_col(self)
+  -- TODO: Re-calculate dimensions on update-preview, in case outline window
+  -- was resized between last preview and next preview?
   ---@type integer
   local outline_winnr = self.s.view.win
   local outline_col = vim.api.nvim_win_get_position(outline_winnr)[2]
@@ -99,20 +76,63 @@ function Preview:calc_col()
 end
 
 ---Get the vertically center-aligned row for preview window
-function Preview:calc_row()
+---@param self outline.Preview|outline.LivePreview
+local function calc_row(self)
   local offset = math.floor((self.outline_height - self.height) / 2) - 1
   return vim.api.nvim_win_get_position(self.s.view.win)[1] + offset
 end
 
----Set and update preview buffer content
+function Preview:create()
-function Preview:set_lines()
+  self.buf = vim.api.nvim_create_buf(false, true)
-  -- TODO: Editable, savable buffer in the preview like VS Code for quick
+  vim.api.nvim_buf_attach(self.buf, false, {
-  -- edits? It can be like LSP. Trigger preview to open, trigger again to focus
+    on_detach = function()
-  -- (so buffer can be edited).
+      self.buf = nil
-  -- This can be achieved by simply opening the buffer from inside the preview
+      self.win = nil
-  -- window.
+    end,
-  -- This also removes the need of manually setting highlights, treesitter etc.
+  })
-  -- The preview window will look exactly the same as in the code window.
+  self.outline_height = vim.api.nvim_win_get_height(self.s.view.win)
+  self.width = self.conf.width
+  self.height = math.max(math.ceil(self.outline_height / 2), self.conf.min_height)
+  self.win = vim.api.nvim_open_win(self.buf, false, {
+    relative = 'editor',
+    height = self.height,
+    width = self.width,
+    bufpos = { 0, 0 },
+    col = calc_col(self),
+    row = calc_row(self),
+    border = self.conf.border,
+    focusable = false,
+  })
+  self:setup()
+  self:update()
+end
+
+
+---Set buf & win options, and setup highlight
+function Preview:setup()
+  vim.api.nvim_win_set_option(self.win, 'winhl', self.conf.winhl)
+  vim.api.nvim_win_set_option(self.win, 'winblend', self.conf.winblend)
+
+  local code_buf = self.s.code.buf
+  local ft = vim.api.nvim_buf_get_option(code_buf, 'filetype')
+  vim.api.nvim_buf_set_option(self.buf, 'syntax', ft)
+
+  local ts_highlight_fn = vim.treesitter.start
+  if not _G._outline_nvim_has[8] then
+    local ok, ts_highlight = pcall(require, 'nvim-treesitter.highlight')
+    if ok then
+      ts_highlight_fn = ts_highlight.attach
+    end
+  end
+  pcall(ts_highlight_fn, self.buf, ft)
+
+  vim.api.nvim_buf_set_option(self.buf, 'bufhidden', 'delete')
+  vim.api.nvim_buf_set_option(self.buf, 'modifiable', false)
+  vim.api.nvim_win_set_option(self.win, 'cursorline', true)
+end
+
+
+function Preview:update()
   local node = self.s:_current_node()
   if not node then
     return
@@ -133,24 +153,17 @@ function Preview:show()
     return
   end
 
-  if self.buf and self.win then
+  if not self.buf or not self.win then
-    self:set_lines()
-  else
     self:create()
-  end
+  else
-
+    self:update()
-  if conf.open_hover_on_preview then
-    providers.action(self.s, 'show_hover', { self.s })
   end
 end
 
 function Preview:close()
-  -- TODO: Why was this in symbols-outline.nvim?
-  -- if self.s:has_code_win() then
   if self.win ~= nil and vim.api.nvim_win_is_valid(self.win) then
     vim.api.nvim_win_close(self.win, true)
   end
-  -- end
 end
 
 function Preview:toggle()
@@ -161,4 +174,102 @@ function Preview:toggle()
   end
 end
 
+---Creates new preview window and sets the content. Calls setup and set_lines.
+function LivePreview:create()
+  self.codewin = self.s.code.win
+  self.initial_cursorline = vim.api.nvim_win_get_option(self.s.code.win, 'cursorline')
+  self.outline_height = vim.api.nvim_win_get_height(self.s.view.win)
+  self.width = self.conf.width
+  self.height = math.max(math.ceil(self.outline_height / 2), self.conf.min_height)
+  self.win = vim.api.nvim_open_win(self.s.code.buf, false, {
+    relative = 'editor',
+    height = self.height,
+    width = self.width,
+    bufpos = { 0, 0 },
+    col = calc_col(self),
+    row = calc_row(self),
+    border = self.conf.border,
+    -- Setting this to disallow using other methods to focus on this window,
+    -- because currently the autocmds from setup() isn't triggering if user did
+    -- not use close() and focus().
+    focusable = false,
+  })
+  self:setup()
+end
+
+---Set buf & win options, and autocmds
+function LivePreview:setup()
+  vim.api.nvim_win_set_option(self.win, 'winhl', self.conf.winhl)
+  vim.api.nvim_win_set_option(self.win, 'winblend', self.conf.winblend)
+  vim.api.nvim_win_set_option(self.win, 'cursorline', true)
+
+  vim.api.nvim_create_autocmd('WinClosed', {
+    pattern = tostring(self.win),
+    once = true,
+    callback = function()
+      self.s.code.win = self.codewin
+      self.win = nil
+    end
+  })
+  vim.api.nvim_create_autocmd('WinEnter', {
+    pattern = tostring(self.win),
+    once = true,
+    callback = function()
+      -- This doesn't work at all?
+      vim.api.nvim_win_set_option(self.win, 'cursorline', self.initial_cursorline)
+    end
+  })
+end
+
+function LivePreview:update(node)
+  vim.api.nvim_win_set_buf(self.win, self.s.code.buf)
+  vim.api.nvim_win_set_cursor(self.win, { node.line + 1, node.character })
+end
+
+function LivePreview:focus()
+  vim.api.nvim_set_current_win(self.win)
+  -- Remove this when the autocmd for WinEnter works above
+  vim.api.nvim_win_set_option(self.win, 'cursorline', self.initial_cursorline)
+end
+
+---Create, focus, or update preview
+function LivePreview:show()
+  if not self.s:has_focus() or #vim.api.nvim_list_wins() < 2 then
+    return
+  end
+
+  local node = self.s:_current_node()
+  if not node then
+    return
+  end
+
+  if not self.win then
+    self:create()
+    vim.api.nvim_win_set_cursor(self.win, { node.line + 1, node.character })
+    self.last_node = node
+    return
+  end
+
+  if node == self.last_node then
+    self:focus()
+  else
+    self:update(node)
+  end
+
+  self.last_node = node
+end
+
+function LivePreview:close()
+  if self.win ~= nil then
+    vim.api.nvim_win_close(self.win, true)
+    -- autocmd from setup is not triggered here?
+    self.win = nil
+    self.s.code.win = self.codewin
+  end
+end
+
+function LivePreview:toggle()
+  self:show()
+end
+
 return Preview

lua/outline/sidebar.lua

@@ -26,13 +26,13 @@ local Sidebar = {}
 ---@field code outline.SidebarCodeState
 ---@field augroup integer
 ---@field provider outline.Provider?
----@field preview outline.Preview
+---@field preview outline.Preview|outline.LivePreview
 
 function Sidebar:new(id)
   return setmetatable({
     id = id,
     view = View:new(),
-    preview = Preview:new(),
+    preview = Preview:new(cfg.o.preview_window),
     code = { buf = 0, win = 0 },
     items = {},
     flats = {},
@@ -138,7 +138,6 @@ function Sidebar:setup_keymaps()
     goto_and_close = { '_goto_and_close', {} },
     down_and_jump = { '_move_and_jump', { 'down' } },
     up_and_jump = { '_move_and_jump', { 'up' } },
-    toggle_preview = { function() self.preview:toggle() end, {} },
     fold_toggle = { '_toggle_fold', {} },
     fold = { '_set_folded', { true } },
     unfold = { '_set_folded', { false } },
@@ -159,6 +158,14 @@ function Sidebar:setup_keymaps()
     ---@diagnostic disable-next-line param-type-mismatch
     self:nmap(name, meth[1], meth[2])
   end
+
+  local toggle_preview
+  if cfg.o.preview_window.auto_preview and cfg.o.preview_window.live then
+    toggle_preview = { function() self.preview:focus() end, {} }
+  else
+    toggle_preview = { function() self.preview:toggle() end, {} }
+  end
+  self:nmap('toggle_preview', toggle_preview[1], toggle_preview[2])
 end
 -- stylua: ignore end
 
@@ -240,7 +247,6 @@ function Sidebar:update_cursor_style()
 
   -- Set cursor color to CursorLine in normal mode
   if hide_cursor then
-    self.original_cursor = vim.o.guicursor
     local cur = vim.o.guicursor:match('n.-:(.-)[-,]')
     vim.opt.guicursor:append('n:' .. cur .. '-Cursorline')
   end