feat: config option to disable previewing a file

lua/oil/config.lua

@@ -144,6 +144,10 @@ local default_config = {
     update_on_cursor_moved = true,
     -- How to open the preview window "load"|"scratch"|"fast_scratch"
     preview_method = "fast_scratch",
+    -- A function that returns true to disable preview on a file e.g. to avoid lag
+    disable_preview = function(filename)
+      return false
+    end,
     -- Window-local options to use for preview window buffers
     win_options = {},
   },
@@ -334,12 +338,14 @@ local M = {}
 ---@class (exact) oil.PreviewWindowConfig
 ---@field update_on_cursor_moved boolean
 ---@field preview_method oil.PreviewMethod
+---@field disable_preview fun(filename: string): boolean
 ---@field win_options table<string, any>
 
 ---@class (exact) oil.ConfirmationWindowConfig : oil.WindowConfig
 
 ---@class (exact) oil.SetupPreviewWindowConfig
 ---@field update_on_cursor_moved? boolean Whether the preview window is automatically updated when the cursor is moved
+---@field disable_preview? fun(filename: string): boolean A function that returns true to disable preview on a file e.g. to avoid lag
 ---@field preview_method? oil.PreviewMethod How to open the preview window
 ---@field win_options? table<string, any> Window-local options to use for preview window buffers
 

lua/oil/init.lua

@@ -541,6 +541,11 @@ M.open_preview = function(opts, callback)
     then
       filebufnr =
         util.read_file_to_scratch_buffer(normalized_url, config.preview_win.preview_method)
+    elseif entry_is_file and config.preview_win.disable_preview(normalized_url) then
+      filebufnr = vim.api.nvim_create_buf(false, true)
+      vim.bo[filebufnr].bufhidden = "wipe"
+      vim.bo[filebufnr].buftype = "nofile"
+      util.render_text(filebufnr, "Preview disabled", { winid = preview_win })
     end
 
     if not filebufnr then