From 9d9a1974cc4147822ce95fede650d99afa2bab2a Mon Sep 17 00:00:00 2001
From: madebyly <me@madebyly.com>
Date: Wed, 18 Feb 2026 00:38:58 -0500
Subject: [PATCH 1/2] fix: stage hunk with existing index file endings

Previously, patches would be generated for hunks the user wanted to
stage with lines concatenated by either:

- a specific platform line ending (currently only Windows) if no file
  exists at the path the hunk came from, or;
- reading the file and determining the line endings of the file by
  checking the line ending of the first line, only.

While both of these worked for entirely new files and / or on platforms
where the environment default line ending is the same as the indexed
file's line endings, it would clobber the indexed file's line endings
when the environment's default line endings differed from the index.

The reason why this only clobbers the indexed files line endings is
because the patch is eventually applied only to the index, not the
working copy.

This would result in the entire file being considered changed in the
diff without additional options to filter out the noise.

This usually only affects Windows due to it using `CRLF` by default, and
only when you work on a repository that primarily commits in `LF` line
endings, but could've probably affected it in the reverse if it was also
vice-versa, with the system being in `LF` while the repository was in
`CRLF`, a setup typical for Windows-specific code repositories being
contributed to cross-platform by developers on other platforms.

(NOTE: I say probably since I haven't had a chance to test that specific
reverse scenario yet, I'm only working off of the core line ending
mismatch problem)

This patch fixes the problem by leveraging Git to determine the existing
indexed file's line endings and using those to concatenate the patch's
lines with, falling back to the existing logic if the file isn't
currently in the repository's index OR if the file has mixed line
endings.

This keeps the line endings consistent as to what would be written to
the repository index on commits.
---
 lua/neogit/lib/git/cli.lua   |  2 ++
 lua/neogit/lib/git/index.lua | 24 +++++++++++++++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/lua/neogit/lib/git/cli.lua b/lua/neogit/lib/git/cli.lua
index c128bc24b..f12abcf45 100644
--- a/lua/neogit/lib/git/cli.lua
+++ b/lua/neogit/lib/git/cli.lua
@@ -312,6 +312,7 @@ end
 ---@field exclude_standard self
 ---@field full_name self
 ---@field error_unmatch self
+---@field eol self
 
 ---@class GitCommandLsTree: GitCommandBuilder
 ---@field full_tree self
@@ -950,6 +951,7 @@ local configurations = {
       exclude_standard = "--exclude-standard",
       full_name = "--full-name",
       error_unmatch = "--error-unmatch",
+      eol = "--eol",
     },
   },
 
diff --git a/lua/neogit/lib/git/index.lua b/lua/neogit/lib/git/index.lua
index 6c4d0f100..d07d32172 100644
--- a/lua/neogit/lib/git/index.lua
+++ b/lua/neogit/lib/git/index.lua
@@ -1,18 +1,36 @@
 local git = require("neogit.lib.git")
 local Path = require("neogit.lib.path")
 local util = require("neogit.lib.util")
+local crlf = "\r\n"
+local lf = "\n"
 
 ---@param path string
 ---@return string
 local function eol_character(path)
+  local _, output = next(git.cli["ls-files"].eol.files(path).call { await = true }.stdout)
+
+  if output ~= nil then
+    local _, _, match = output:find("i/(%w+)")
+
+    if match ~= nil then
+      if match == crlf then
+        return crlf
+      elseif match == lf then
+        return lf
+      end
+    end
+  end
+
+  -- Handle the `mixed` line ending case OR lack of a file in the index by deferring to platform defaults for EOL
+  -- or by reading the current working file and determining its line ending that way
   if not Path:new(path):exists() then
-    return (vim.fn.has("win32") == 1 or vim.fn.has("win64") == 1) and "\r\n" or "\n"
+    return (vim.fn.has("win32") == 1 or vim.fn.has("win64") == 1) and crlf or lf
   end
   local lines = vim.fn.readfile(path, "b", 1)
   if lines[1] and lines[1]:find("\r") then
-    return "\r\n"
+    return crlf
   else
-    return "\n"
+    return lf
   end
 end
 

From bdfb0768bf3f45044045ae55c33e7bc78c8cb357 Mon Sep 17 00:00:00 2001
From: Ly <me@madebyly.com>
Date: Mon, 21 Sep 2026 19:57:54 -0400
Subject: [PATCH 2/2] fix: check exact match result

This was an erroneous change where the variable was used even though the
value returned from `git ls-files --eol` doesn't include the leading
slash.

Using the "constant" doesn't actually perform the match correctly.
---
 lua/neogit/lib/git/index.lua | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lua/neogit/lib/git/index.lua b/lua/neogit/lib/git/index.lua
index d07d32172..abdabaf5c 100644
--- a/lua/neogit/lib/git/index.lua
+++ b/lua/neogit/lib/git/index.lua
@@ -13,9 +13,9 @@ local function eol_character(path)
     local _, _, match = output:find("i/(%w+)")
 
     if match ~= nil then
-      if match == crlf then
+      if match == 'crlf' then
         return crlf
-      elseif match == lf then
+      elseif match == 'lf' then
         return lf
       end
     end