feat: skip loading large files in diffs, which cause hangs

Author: stevenxxiu

README.md

@@ -100,6 +100,8 @@ neogit.setup {
   log_date_format = nil,
   -- When set, used to format the diff. Requires *baleia* to colorize text with ANSI escape sequences. An example for `Delta` is `{ 'delta', '--width', '117' }`. For `Delta`, hyperlinks must be disabled in its git config section, for text to be colorized properly. It's recommended to set `disable_context_highlighting = true`, otherwise when the cursor is in the hunk, we lose background highlighting
   log_pager = nil,
+  -- Max file size for a diff to be shown
+  diff_max_file_size = 200000,
   -- Show message with spinning animation when a git command is running.
   process_spinner = false,
   -- Used to generate URL's for branch popup action "pull request", "open commit" and "open tree"

doc/neogit.txt

@@ -118,6 +118,8 @@ to Neovim users.
     -- for text to be colorized properly. It's recommended to set `disable_context_highlighting = true`, otherwise when
     -- the cursor is in the hunk, we lose background highlighting
     log_pager = nil,
+    -- Max file size for a diff to be shown
+    diff_max_file_size = 200000,
     -- Used to generate URL's for branch popup action "pull request" or opening a commit.
     git_services = {
         ["github.com"] = {

lua/neogit/config.lua

@@ -346,6 +346,7 @@ end
 ---@field commit_date_format? string Commit date format
 ---@field log_date_format? string Log date format
 ---@field log_pager? [string] Log pager
+---@field diff_max_file_size? [number] Max file size for a diff to be shown
 ---@field disable_hint? boolean Remove the top hint in the Status buffer
 ---@field disable_context_highlighting? boolean Disable context highlights based on cursor position
 ---@field disable_signs? boolean Special signs to draw for sections etc. in Neogit
@@ -403,6 +404,7 @@ function M.get_default_values()
     commit_date_format = nil,
     log_date_format = nil,
     log_pager = nil,
+    diff_max_file_size = 200000,
     process_spinner = false,
     filewatcher = {
       enabled = true,

lua/neogit/lib/git/diff.lua

@@ -285,6 +285,19 @@ local function build_metatable(f, raw_output_fn)
     __index = function(self, method)
       if method == "diff" then
         self.diff = a.util.block_on(function()
+          local stat = vim.uv.fs_stat(f.absolute_path)
+          if stat == nil or stat.size > config.values.diff_max_file_size then
+            logger.debug("[DIFF] Skipped loading diff as file too large: " .. f.name)
+            return {
+              kind = nil,
+              lines = {},
+              file = f.name,
+              info = {},
+              stats = {},
+              hunks = {},
+              pager_contents = {},
+            }
+          end
           logger.debug("[DIFF] Loading diff for: " .. f.name)
           return parse_diff(unpack(raw_output_fn()))
         end)