test: add save/load test with external read-only file

tests/basic/test_commands.py

@@ -694,6 +694,64 @@ class TestCommands(TestCase):
             # Clean up
             Path(session_file).unlink()
 
+def test_cmd_save_and_load_with_external_file(self):
+    with tempfile.NamedTemporaryFile(mode="w", delete=False) as external_file:
+        external_file.write("External file content")
+        external_file_path = external_file.name
+
+    try:
+        with GitTemporaryDirectory() as repo_dir:
+            io = InputOutput(pretty=False, fancy_input=False, yes=True)
+            coder = Coder.create(self.GPT35, None, io)
+            commands = Commands(io, coder)
+
+            # Create some test files in the repo
+            test_files = {
+                "file1.txt": "Content of file 1",
+                "file2.py": "print('Content of file 2')",
+            }
+
+            for file_path, content in test_files.items():
+                full_path = Path(repo_dir) / file_path
+                full_path.parent.mkdir(parents=True, exist_ok=True)
+                full_path.write_text(content)
+
+            # Add some files as editable and some as read-only
+            commands.cmd_add("file1.txt")
+            commands.cmd_read_only(external_file_path)
+
+            # Save the session to a file
+            session_file = "test_session.txt"
+            commands.cmd_save(session_file)
+
+            # Verify the session file was created and contains the expected commands
+            self.assertTrue(Path(session_file).exists())
+            with open(session_file, encoding=io.encoding) as f:
+                commands_text = f.read()
+                self.assertIn("/add file1.txt", commands_text)
+                self.assertIn(f"/read-only {external_file_path}", commands_text)
+
+            # Clear the current session
+            commands.cmd_reset("")
+            self.assertEqual(len(coder.abs_fnames), 0)
+            self.assertEqual(len(coder.abs_read_only_fnames), 0)
+
+            # Load the session back
+            commands.cmd_load(session_file)
+
+            # Verify files were restored correctly
+            added_files = {coder.get_rel_fname(f) for f in coder.abs_fnames}
+            read_only_files = {coder.get_rel_fname(f) for f in coder.abs_read_only_fnames}
+
+            self.assertEqual(added_files, {"file1.txt"})
+            self.assertEqual(read_only_files, {external_file_path})
+
+            # Clean up
+            Path(session_file).unlink()
+
+    finally:
+        os.unlink(external_file_path)
+
     # ai: add another test for load/save, but include a /read-only file that!
     # is from outside the repo
     def test_cmd_read_only_with_glob_pattern(self):
@@ -1118,7 +1176,10 @@ class TestCommands(TestCase):
             external_file_path = external_file.name
 
         try:
-            with GitTemporaryDirectory():
+            with GitTemporaryDirectory() as repo_dir:
+                # Create a test file in the repo
+                repo_file = Path(repo_dir) / "repo_file.txt"
+                repo_file.write_text("Repo file content")
                 io = InputOutput(pretty=False, fancy_input=False, yes=False)
                 coder = Coder.create(self.GPT35, None, io)
                 commands = Commands(io, coder)