review

- [P2] Ignore comment text when validating continued values —
  /Users/byron/dev/github.com/gitpython-developers/GitPython.fix-config-unquoted
  -escape-parsing/git/config.py:576-577 With `k = one\` followed by ` two
  # C:\Users`, the joined value still contains the second line's comment.
  This check treats its `\U` as an unknown escape and skips `parse_value()`,
  returning `one two # C:\Users` instead of `one two`, unlike Git and `main`.
  Updating an unrelated option then persists the comment as part of the value.
  Strip or skip unquoted comment text before validating escapes.

- [P2] Preserve whitespace before an EOF continuation backslash —
  /Users/byron/dev/github.com/gitpython-developers/GitPython.fix-config-unquoted
  -escape-parsing/git/config.py:652-653 If the final config line is `k = value
  \`, with or without a terminating newline, Git and `main` return `"value
  "`. The EOF branch removes the backslash first, so this newly applied
  `parse_value()` discards the preceding space and returns `"value"`. Updating
  an unrelated option also persists that change. Preserve whitespace made
  significant by the continuation when decoding.

Assisted-by: GPT 6.1 Sol
Co-authored-by: GPT 6.1 Sol <codex@openai.com>

Author: Byron

git/config.py

@@ -632,13 +632,15 @@ def escapes_are_known(value: str) -> bool:
                         # next line is appended before the complete value is
                         # parsed. An even number means the last backslash is
                         # escaped and the value ends there.
+                        eof_continuation = False
                         while True:
                             if not is_line_continuation(optval):
                                 break
                             continuation = fp.readline()
                             if not continuation:
-                                # Backslash at end of file: git drops it.
-                                optval = optval[:-1]
+                                # Keep the backslash until parsing so preceding
+                                # whitespace is significant even though git drops it.
+                                eof_continuation = True
                                 break
                             lineno = lineno + 1
                             joined = continuation.decode(defenc)
@@ -649,8 +651,11 @@ def escapes_are_known(value: str) -> bool:
                         # values, but only a value in which every backslash is part
                         # of a known escape is decoded, so that a Windows path keeps
                         # its backslashes instead of losing them one escape at a time.
+                        optval, _ = strip_inline_comment(optval)
                         if escapes_are_known(optval):
                             optval = parse_value(optval)
+                        elif eof_continuation:
+                            optval = optval[:-1]
                     elif quote_open:
                         # Opens quoting and does not close: appears to start multi-line quoting.
                         is_multi_line = True

test/test_config.py

@@ -378,6 +378,33 @@ def test_backslash_line_continuation(self):
             key = "co" if section == "alias" else "k"
             self.assertEqual(config.get_value(section, key), expected)
 
+    @with_rw_directory
+    def test_continued_values_preserve_comments_and_eof_whitespace(self, rw_dir):
+        cases = [
+            (b"one\\\n two # C:\\Users\n", "one two"),
+            (b"one\\\n two ; C:\\Users\n", "one two"),
+            (b"one\\\n two\\tthree # C:\\Users\n", "one two\tthree"),
+            (b'one\\\n "two # three" # C:\\Users\n', "one two # three"),
+            (b"value \\", "value "),
+            (b"value \\\n", "value "),
+            (b"value \t\\\n", "value \t"),
+            (b"one\\\n two \\\n", "one two "),
+            (b"C:\\Users \\\n", "C:\\Users "),
+        ]
+        config_path = osp.join(rw_dir, "config")
+        for value, expected in cases:
+            with self.subTest(value=value):
+                with open(config_path, "wb") as config_file:
+                    config_file.write(b"[a]\n\tk = " + value)
+
+                with GitConfigParser(config_path, read_only=False) as config:
+                    self.assertEqual(config.get_value("a", "k"), expected)
+                    config.set_value("other", "value", "updated")
+
+                with GitConfigParser(config_path) as config:
+                    self.assertEqual(config.get_value("a", "k"), expected)
+                    self.assertEqual(config.get_value("other", "value"), "updated")
+
     def test_get_value_reads_git_boolean_spellings(self):
         # git accepts yes/no and on/off as well as true/false, and getboolean on
         # this class already did. get_value returned them as strings, so "no" and