Function test_disk_usage_with_clones

datafusion/execution/src/disk_manager.rs:653–716

()

    #[test]
    fn test_disk_usage_with_clones() -> Result<()> {
        use std::io::Write;

        let dm = Arc::new(DiskManagerBuilder::default().build()?);
        let mut temp_file = dm.create_tmp_file("Testing")?;

        // Write some data
        temp_file.inner().as_file().write_all(b"test data")?;
        temp_file.update_disk_usage()?;

        let usage_after_write = temp_file.current_disk_usage();
        assert!(usage_after_write > 0);
        assert_eq!(dm.used_disk_space(), usage_after_write);

        // Clone the file
        let clone1 = temp_file.clone();
        let clone2 = temp_file.clone();

        // All clones should see the same disk usage
        assert_eq!(clone1.current_disk_usage(), usage_after_write);
        assert_eq!(clone2.current_disk_usage(), usage_after_write);

        // Global disk usage should still be the same (not multiplied by number of clones)
        assert_eq!(dm.used_disk_space(), usage_after_write);

        // Write more data through one clone
        clone1.inner().as_file().write_all(b" more data")?;
        let mut mutable_clone1 = clone1;
        mutable_clone1.update_disk_usage()?;

        let new_usage = mutable_clone1.current_disk_usage();
        assert!(new_usage > usage_after_write);

        // All clones should see the updated disk usage
        assert_eq!(temp_file.current_disk_usage(), new_usage);
        assert_eq!(clone2.current_disk_usage(), new_usage);
        assert_eq!(mutable_clone1.current_disk_usage(), new_usage);

        // Global disk usage should reflect the new size (not multiplied)
        assert_eq!(dm.used_disk_space(), new_usage);

        // Drop one clone
        drop(mutable_clone1);

        // Disk usage should NOT change (other clones still exist)
        assert_eq!(dm.used_disk_space(), new_usage);
        assert_eq!(temp_file.current_disk_usage(), new_usage);
        assert_eq!(clone2.current_disk_usage(), new_usage);

        // Drop another clone
        drop(clone2);

        // Disk usage should still NOT change (original still exists)
        assert_eq!(dm.used_disk_space(), new_usage);
        assert_eq!(temp_file.current_disk_usage(), new_usage);

        // Drop the original
        drop(temp_file);