From 7f68ae0fce797850ffffb39ea23dd1a714c74e47 Mon Sep 17 00:00:00 2001
From: Antti Kaihola <13725+akaihola@users.noreply.github.com>
Date: Mon, 30 Dec 2024 21:02:12 +0200
Subject: [PATCH 1/3] test: add failing test which splits lines on x85
 character

---
 src/darkgraylib/tests/test_utils.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/darkgraylib/tests/test_utils.py b/src/darkgraylib/tests/test_utils.py
index e926f38..be1b181 100644
--- a/src/darkgraylib/tests/test_utils.py
+++ b/src/darkgraylib/tests/test_utils.py
@@ -138,6 +138,12 @@ def test_textdocument_encoded_string(encoding, newline, expect):
     dict(
         doc=TextDocument(string="zéro\r\nun\r\n", newline="\r\n"), expect=("zéro", "un")
     ),
+    dict(
+        doc=TextDocument(
+            string="# coding: iso-8859-5\n# б\x85б\x86\n", encoding="iso-8859-5"
+        ),
+        expect=("# coding: iso-8859-5", "# б\x85б\x86"),
+    ),
 )
 def test_textdocument_lines(doc, expect):
     """TextDocument.lines is correct after parsing a string with different newlines"""

From e2cff510f677a8a13e9da265bc6af5c16bb30fad Mon Sep 17 00:00:00 2001
From: Antti Kaihola <13725+akaihola@users.noreply.github.com>
Date: Mon, 30 Dec 2024 21:02:36 +0200
Subject: [PATCH 2/3] fix: only split lines at Python's universal newlines

---
 src/darkgraylib/utils.py | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/darkgraylib/utils.py b/src/darkgraylib/utils.py
index fe933f4..65088e8 100644
--- a/src/darkgraylib/utils.py
+++ b/src/darkgraylib/utils.py
@@ -22,6 +22,22 @@ def detect_newline(string: str) -> str:
     return "\n"
 
 
+def normalize_newlines(string: str) -> str:
+    """Normalize newlines in a string to LF"""
+    return io.IncrementalNewlineDecoder(None, True).decode(string)
+
+
+def splitlines(string: str) -> list[str]:
+    """Split a string into lines at universal newlines."""
+    if not string:
+        return []
+    return (
+        normalize_newlines(string)  # Normalize newlines to LF
+        .rstrip("\n")  # Remove trailing newline
+        .split("\n")  # Split into lines
+    )
+
+
 class TextDocument:
     """Store & handle a multi-line text document, either as a string or list of lines"""
 
@@ -65,7 +81,7 @@ def encoded_string(self) -> bytes:
     def lines(self) -> TextLines:
         """Return the document as a list of lines converting and caching if necessary"""
         if self._lines is None:
-            self._lines = tuple((self._string or "").splitlines())
+            self._lines = tuple(splitlines(self._string or ""))
         return self._lines
 
     @property

From 3035dccb93430a1c0d0a0367e522d316b170f85d Mon Sep 17 00:00:00 2001
From: Antti Kaihola <13725+akaihola@users.noreply.github.com>
Date: Fri, 3 Jan 2025 18:35:33 +0200
Subject: [PATCH 3/3] docs: update the change log

---
 CHANGES.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGES.rst b/CHANGES.rst
index d4a7274..b1a8041 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -13,6 +13,8 @@ Removed
 
 Fixed
 -----
+- Only split input files at Python's universal newlines (LF, CRLF, CR), not on more
+  exotic newline sequences. This fixes some edge cases in Darker.
 
 
 2.1.0_ - 2024-11-19