rust-rocksdb/test/test_iterator.rs

use rocksdb::{Options, RocksDB, Writable, Direction};
use std;


#[test]
pub fn test_iterator() {
    let path = "_rust_rocksdb_iteratortest";
    {
        let k1:Box<[u8]> = b"k1".to_vec().into_boxed_slice();
        let k2:Box<[u8]> = b"k2".to_vec().into_boxed_slice();
        let k3:Box<[u8]> = b"k3".to_vec().into_boxed_slice();
        let k4:Box<[u8]> = b"k4".to_vec().into_boxed_slice();
        let v1:Box<[u8]> = b"v1111".to_vec().into_boxed_slice();
        let v2:Box<[u8]> = b"v2222".to_vec().into_boxed_slice();
        let v3:Box<[u8]> = b"v3333".to_vec().into_boxed_slice();
        let v4:Box<[u8]> = b"v4444".to_vec().into_boxed_slice();
        let mut db = RocksDB::open_default(path).unwrap();
        let p = db.put(&*k1, &*v1);
        assert!(p.is_ok());
        let p = db.put(&*k2, &*v2);
        assert!(p.is_ok());
        let p = db.put(&*k3, &*v3);
        assert!(p.is_ok());
        let mut view1 = db.iterator();
        let expected = vec![(k1, v1), (k2, v2), (k3, v3)];
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected);
        }
        // Test that it's reusable a few times
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected);
        }
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected);
        }
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected);
        }
        // Test it in reverse a few times
        {
            let mut iterator1 = view1.from_end();
            let mut tmp_vec = iterator1.collect::<Vec<_>>();
            tmp_vec.reverse();
            assert_eq!(tmp_vec, expected);
        }
        {
            let mut iterator1 = view1.from_end();
            let mut tmp_vec = iterator1.collect::<Vec<_>>();
            tmp_vec.reverse();
            assert_eq!(tmp_vec, expected);
        }
        {
            let mut iterator1 = view1.from_end();
            let mut tmp_vec = iterator1.collect::<Vec<_>>();
            tmp_vec.reverse();
            assert_eq!(tmp_vec, expected);
        }
        {
            let mut iterator1 = view1.from_end();
            let mut tmp_vec = iterator1.collect::<Vec<_>>();
            tmp_vec.reverse();
            assert_eq!(tmp_vec, expected);
        }
        {
            let mut iterator1 = view1.from_end();
            let mut tmp_vec = iterator1.collect::<Vec<_>>();
            tmp_vec.reverse();
            assert_eq!(tmp_vec, expected);
        }
        // Try it forward again
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected);
        }
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected);
        }

        let mut view2 = db.iterator();
        let p = db.put(k4, v4);
        assert!(p.is_ok());
        let mut view3 = db.iterator();
        let expected2 = vec![(k1, v1), (k2, v2), (k3, v3), (k4, v4)];
        {
            let mut iterator1 = view1.from_start();
            assert_eq!(iterator1.collect::<Vec<_>>(), expected2);
        }
//TODO continue implementing tests!
        println!("See the output of the third iter");
        for (k,v) in view3.from_start() {
            //println!("Hello {}: {}", std::str::from_utf8(k).unwrap(), std::str::from_utf8(v).unwrap());
        }
        println!("now the 3rd iter from k2 fwd");
        for (k,v) in view3.from(b"k2", Direction::forward) {
            //println!("Hello {}: {}", std::str::from_utf8(k).unwrap(), std::str::from_utf8(v).unwrap());
        }
        println!("now the 3rd iter from k2 and back");
        for (k,v) in view3.from(b"k2", Direction::reverse) {
            //println!("Hello {}: {}", std::str::from_utf8(k).unwrap(), std::str::from_utf8(v).unwrap());
        }
    }
    let opts = Options::new();
    assert!(RocksDB::destroy(&opts, path).is_ok());
}