add another btree test

crates/datastructures/src/btree.rs

@@ -153,7 +153,7 @@ mod test {
     }
 
     #[test]
-    fn test_insert() {
+    fn test_insert_easy() {
         let mut tree = BTree::<u32>::new(DEFAULT_DEGREE);
         let data = &[19, 125, 25, 16, 2, 73, 384, 435, 12924, 42, 125251, 2548];
 
@@ -165,4 +165,25 @@ mod test {
             assert!(tree.has(*d))
         }
     }
+
+    #[test]
+    fn test_insert_many() {
+        let mut tree = BTree::<u32>::new(DEFAULT_DEGREE);
+        let mut data = vec![19, 125, 25, 16, 2, 73, 384, 435, 12924, 42, 125251, 2548];
+
+        for _ in 0..10 {
+            data.extend(data.clone());
+        }
+
+        // data has 12288 elements here! This is a lot, but should be reasonably possible for a btree.
+        println!("len of data: {}", data.len());
+
+        for d in &data {
+            tree.insert(*d)
+        }
+
+        for d in &data {
+            assert!(tree.has(*d))
+        }
+    }
 }