fixes

codex-rs/apply-patch/src/lib.rs

@@ -44,6 +44,9 @@ use crate::invocation::ExtractHeredocError;
 /// surface.
 pub const CODEX_CORE_APPLY_PATCH_ARG1: &str = "--codex-run-as-apply-patch";
 
+/// Enables CRLF preservation for the standalone `apply_patch` command.
+pub const APPLY_PATCH_PRESERVE_CRLF_ARG: &str = "--preserve-crlf";
+
 /// Controls optional behavior when parsing or applying a patch.
 #[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
 pub struct ApplyPatchOptions {

codex-rs/apply-patch/src/parser.rs

@@ -442,8 +442,8 @@ fn parse_update_file_chunk(
                 match line_contents.chars().next() {
                     None => {
                         // Interpret this as an empty line.
-                        chunk.old_lines.push(String::new());
-                        chunk.new_lines.push(String::new());
+                        chunk.old_lines.push(line.to_string());
+                        chunk.new_lines.push(line.to_string());
                     }
                     Some(' ') => {
                         chunk.old_lines.push(line[1..].to_string());
@@ -587,6 +587,34 @@ fn test_update_file_chunk() {
     );
 }
 
+#[test]
+fn test_update_file_chunk_preserves_crlf_for_bare_empty_context_line() {
+    assert_eq!(
+        parse_update_file_chunk(
+            &["@@\r", " before\r", "\r", " after\r", "*** End Patch\r"],
+            /*line_number*/ 123,
+            /*allow_missing_context*/ false,
+        ),
+        Ok((
+            UpdateFileChunk {
+                change_context: None,
+                old_lines: vec![
+                    "before\r".to_string(),
+                    "\r".to_string(),
+                    "after\r".to_string(),
+                ],
+                new_lines: vec![
+                    "before\r".to_string(),
+                    "\r".to_string(),
+                    "after\r".to_string(),
+                ],
+                is_end_of_file: false,
+            },
+            4,
+        ))
+    );
+}
+
 #[test]
 fn test_parse_patch() {
     assert_eq!(

codex-rs/apply-patch/src/standalone_executable.rs

@@ -1,8 +1,6 @@
 use std::io::Read;
 use std::io::Write;
 
-const PRESERVE_CRLF_FLAG: &str = "--preserve-crlf";
-
 pub fn main() -> ! {
     let exit_code = run_main();
     std::process::exit(exit_code);
@@ -17,7 +15,7 @@ pub fn run_main() -> i32 {
     let _argv0 = args.next();
     let first_arg = args.next();
     let (options, patch_arg) = match first_arg {
-        Some(arg) if arg.to_str() == Some(PRESERVE_CRLF_FLAG) => {
+        Some(arg) if arg == crate::APPLY_PATCH_PRESERVE_CRLF_ARG => {
             (crate::ApplyPatchOptions::preserve_crlf(), args.next())
         }
         patch_arg => (crate::ApplyPatchOptions::default(), patch_arg),