keep/src/tests/modes/save_tests.rs

#[cfg(test)]
mod tests {
    use tempfile::tempdir;
    use std::fs::File;
    use std::io::Write;

    #[test]
    fn test_save_mode_basic_functionality() {
        // Create a temporary directory for testing
        let dir = tempdir().expect("Failed to create temporary directory");
        let file_path = dir.path().join("test_input.txt");
        
        // Create a test file
        {
            let mut file = File::create(&file_path).expect("Failed to create test file");
            writeln!(file, "test content for save mode").expect("Failed to write to test file");
        }
        
        // Verify file was created
        assert!(file_path.exists());
        
        // Note: Actual save mode testing would require integration with the keep database
        // and compression engines, which is complex for unit tests
    }

    #[test]
    fn test_save_mode_empty_file() {
        // Create a temporary directory for testing
        let dir = tempdir().expect("Failed to create temporary directory");
        let file_path = dir.path().join("empty_test.txt");
        
        // Create an empty test file
        {
            let _file = File::create(&file_path).expect("Failed to create empty test file");
            // File is automatically closed when it goes out of scope
        }
        
        // Verify empty file was created
        assert!(file_path.exists());
        let metadata = std::fs::metadata(&file_path).expect("Failed to get file metadata");
        assert_eq!(metadata.len(), 0);
    }
}