add delete files in range with delete range test (#128)

Cargo.toml

@@ -33,3 +33,4 @@ path = "librocksdb_sys"
 
 [dev-dependencies]
 byteorder = "1.0.0"
+rand = "0.3"

tests/test.rs

@@ -2,6 +2,7 @@ extern crate byteorder;
 extern crate crc;
 extern crate rocksdb;
 extern crate tempdir;
+extern crate rand;
 
 mod test_iterator;
 mod test_multithreaded;

tests/test_delete_files_in_range.rs

@@ -11,6 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use rand::{self, Rng};
 use rocksdb::*;
 use tempdir::TempDir;
 
@@ -100,3 +101,69 @@ fn test_delete_files_in_range_with_snap() {
     // sst2 has been dropped.
     assert_eq!(count, 6);
 }
+
+#[test]
+fn test_delete_files_in_range_with_delete_range() {
+    // Regression test for https://github.com/facebook/rocksdb/issues/2833.
+    let path = TempDir::new("_rocksdb_test_delete_files_in_range_with_delete_range").expect("");
+    let path_str = path.path().to_str().unwrap();
+
+    let sst_size = 1 << 10;
+    let value_size = 8 << 10;
+    let mut opts = DBOptions::new();
+    opts.create_if_missing(true);
+    let mut cf_opts = ColumnFamilyOptions::new();
+    cf_opts.set_target_file_size_base(sst_size);
+    cf_opts.set_level_zero_file_num_compaction_trigger(10);
+
+    let db = DB::open_cf(opts, path_str, vec![("default", cf_opts)]).unwrap();
+
+    // Flush 5 files in level 0.
+    // File i will contain keys i and i+1.
+    for i in 0..5 {
+        let k1 = format!("{}", i);
+        let k2 = format!("{}", i + 1);
+        let mut v = vec![0; value_size];
+        rand::thread_rng().fill_bytes(&mut v);
+        db.put(k1.as_bytes(), v.as_slice()).unwrap();
+        db.put(k2.as_bytes(), v.as_slice()).unwrap();
+        db.flush(true).unwrap();
+    }
+
+    // Hold a snapshot to prevent the following delete range from dropping keys above.
+    let snapshot = db.snapshot();
+    db.delete_range(b"0", b"6").unwrap();
+    db.flush(true).unwrap();
+    // After this, we will have 3 files in level 1.
+    // File i will contain keys i and i+1, and the delete range [0, 6).
+    db.compact_range(None, None);
+    drop(snapshot);
+
+    // Before the fix, the file in the middle with keys 2 and 3 will be deleted,
+    // which can be a problem when we compact later. After the fix, no file will
+    // be deleted since they have an overlapped delete range [0, 6).
+    db.delete_file_in_range(b"1", b"4").unwrap();
+
+    // Flush a file with keys 4 and 5 to level 0.
+    for i in 4..5 {
+        let k1 = format!("{}", i);
+        let k2 = format!("{}", i + 1);
+        let mut v = vec![0; value_size];
+        rand::thread_rng().fill_bytes(&mut v);
+        db.put(k1.as_bytes(), v.as_slice()).unwrap();
+        db.put(k2.as_bytes(), v.as_slice()).unwrap();
+        db.flush(true).unwrap();
+    }
+
+    // After this, the delete range [0, 6) will drop all entries before it, so
+    // we should have only keys 4 and 5.
+    db.compact_range(None, None);
+
+    let mut it = db.iter();
+    it.seek(SeekKey::Start);
+    assert!(it.valid());
+    assert_eq!(it.key(), b"4");
+    assert!(it.next());
+    assert_eq!(it.key(), b"5");
+    assert!(!it.next());
+}