Create tree_l0_point_read

tests/tree_l0_point_read

@@ -0,0 +1,43 @@
+use lsm_tree::AbstractTree;
+use test_log::test;
+
+#[test]
+fn tree_l0_point_read() -> lsm_tree::Result<()> {
+    let folder = tempfile::tempdir()?;
+    let path = folder.path();
+
+    let tree = lsm_tree::Config::new(path).open_as_blob_tree()?;
+
+    tree.insert("a", "a", 0);
+    tree.insert("b", "b", 0);
+    tree.insert("c", "c", 0);
+    tree.flush_active_memtable(0)?;
+
+    tree.insert("a", "a", 1);
+    tree.insert("b", "b", 1);
+    tree.insert("c", "c", 1);
+    tree.flush_active_memtable(0)?;
+
+    tree.insert("a", "A", 2);
+    tree.insert("b", "B", 2);
+    tree.insert("c", "C", 2);
+    tree.flush_active_memtable(0)?;
+
+    tree.insert("d", "d", 3);
+    tree.insert("e", "e", 3);
+    tree.insert("f", "f", 3);
+    tree.flush_active_memtable(0)?;
+
+    tree.insert("g", "g", 3);
+    tree.flush_active_memtable(0)?;
+
+    assert_eq!(b"A", &*tree.get("a")?.unwrap());
+    assert_eq!(b"B", &*tree.get("b")?.unwrap());
+    assert_eq!(b"C", &*tree.get("c")?.unwrap());
+    assert_eq!(b"d", &*tree.get("d")?.unwrap());
+    assert_eq!(b"e", &*tree.get("e")?.unwrap());
+    assert_eq!(b"f", &*tree.get("f")?.unwrap());
+    assert_eq!(b"g", &*tree.get("g")?.unwrap());
+
+    Ok(())
+}