feat: add layout.resize_to_content config option

lua/aerial/config.lua

@@ -26,6 +26,9 @@ local default_options = {
     --   window - open aerial to the right/left of the current window
     placement = "window",
 
+    -- When the symbols change, resize the aerial window (within min/max constraints) to fit
+    resize_to_content = true,
+
     -- Preserve window size equality with (:help CTRL-W_=)
     preserve_equality = false,
   },

lua/aerial/render.lua

@@ -42,8 +42,10 @@ local function resize_all_wins(aer_bufnr, preferred_width, preferred_height)
       -- padding out whitespace. The gutter needs to adjust the total window
       -- size, but it doesn't take space away from the content.
       max_width = math.max(max_width, width - gutter)
-      vim.api.nvim_win_set_width(winid, width)
-      util.save_width(aer_bufnr, width)
+      if config.layout.resize_to_content or vim.b[aer_bufnr].aerial_width == nil then
+        vim.api.nvim_win_set_width(winid, width)
+      end
+      vim.b[aer_bufnr].aerial_width = width
 
       -- Reposition floating windows
       if util.is_floating_win(winid) then

lua/aerial/util.lua

@@ -28,22 +28,8 @@ end
 ---@param str string
 ---@return string
 M.remove_newlines = function(str)
-  return string.gsub(str, "\n", " ")
-end
-
----@param winid integer Window to restore
----@param bufnr integer Aerial buffer
-M.restore_width = function(winid, bufnr)
-  local ok, width = pcall(vim.api.nvim_buf_get_var, bufnr, "aerial_width")
-  if ok then
-    vim.api.nvim_win_set_width(winid, width)
-  end
-end
-
----@param bufnr integer
----@param width integer
-M.save_width = function(bufnr, width)
-  vim.api.nvim_buf_set_var(bufnr, "aerial_width", width)
+  local ret = string.gsub(str, "\n", " ")
+  return ret
 end
 
 ---@param winid nil|integer

lua/aerial/window.lua

@@ -107,7 +107,10 @@ local function setup_aerial_win(src_winid, aer_winid, aer_bufnr)
   vim.api.nvim_win_set_var(src_winid, "aerial_win", aer_winid)
   -- Set the filetype only after we enter the buffer so that ftplugins behave properly
   vim.api.nvim_buf_set_option(aer_bufnr, "filetype", "aerial")
-  util.restore_width(aer_winid, aer_bufnr)
+  local width = vim.b[aer_bufnr].aerial_width
+  if width then
+    vim.api.nvim_win_set_width(aer_winid, width)
+  end
   if config.layout.preserve_equality then
     vim.cmd.wincmd({ args = { "=" } })
   end