feat: Add test for --read option

tests/basic/test_main.py

@@ -396,3 +396,17 @@ class TestMain(TestCase):
                     output=DummyOutput(),
                 )
                 MockRepoMap.assert_called_once()
+
+    def test_read_option(self):
+        with GitTemporaryDirectory():
+            test_file = "test_file.txt"
+            Path(test_file).touch()
+            
+            coder = main(
+                ["--read", test_file, "--exit", "--yes"],
+                input=DummyInput(),
+                output=DummyOutput(),
+                return_coder=True,
+            )
+            
+            self.assertIn(str(Path(test_file).resolve()), coder.abs_read_only_fnames)