test: add tests for merge trait of operations on various data struc…

…tures, including conflict scenarios and checking for empty structures

crates/core/tests/test_merge.rs

@@ -0,0 +1,122 @@
+use std::collections::{BTreeMap, BTreeSet};
+
+use bdk_core::Merge;
+
+#[test]
+fn test_btree_map_merge() {
+    let mut map1: BTreeMap<i32, &str> = BTreeMap::new();
+    map1.insert(1, "a");
+    let mut map2: BTreeMap<i32, &str> = BTreeMap::new();
+    map2.insert(2, "b");
+
+    map1.merge(map2);
+
+    assert_eq!(map1.len(), 2);
+    assert_eq!(map1.get(&1), Some(&"a"));
+    assert_eq!(map1.get(&2), Some(&"b"));
+}
+
+#[test]
+fn test_btree_set_merge() {
+    let mut set1: BTreeSet<i32> = BTreeSet::new();
+    set1.insert(1);
+    let mut set2: BTreeSet<i32> = BTreeSet::new();
+    set2.insert(2);
+
+    set1.merge(set2);
+
+    assert_eq!(set1.len(), 2);
+    assert!(set1.contains(&1));
+    assert!(set1.contains(&2));
+}
+
+#[test]
+fn test_vec_merge() {
+    let mut vec1 = vec![1, 2, 3];
+    let vec2 = vec![4, 5, 6];
+
+    vec1.merge(vec2);
+
+    assert_eq!(vec1, vec![1, 2, 3, 4, 5, 6]);
+}
+
+#[test]
+fn test_tuple_merge() {
+    let mut tuple1 = (vec![1, 2], BTreeSet::from([3]));
+    let tuple2 = (vec![3, 4], BTreeSet::from([4]));
+
+    tuple1.merge(tuple2);
+
+    assert_eq!(tuple1.0, vec![1, 2, 3, 4]);
+    assert_eq!(tuple1.1.len(), 2);
+    assert!(tuple1.1.contains(&3));
+    assert!(tuple1.1.contains(&4));
+}
+
+#[test]
+fn test_is_empty() {
+    let map: BTreeMap<i32, i32> = BTreeMap::new();
+    assert!(<BTreeMap<i32, i32>>::is_empty(&map));
+
+    let set: BTreeSet<i32> = BTreeSet::new();
+    assert!(<BTreeSet<i32>>::is_empty(&set));
+
+    let vec: Vec<i32> = Vec::new();
+    assert!(<Vec<i32>>::is_empty(&vec));
+}
+
+#[test]
+fn test_take() {
+    let mut map: BTreeMap<i32, i32> = BTreeMap::new();
+    map.insert(1, 1);
+    let taken_map = map.take();
+    assert!(taken_map.is_some());
+    assert!(map.is_empty());
+
+    let mut set: BTreeSet<i32> = BTreeSet::new();
+    set.insert(1);
+    let taken_set = <BTreeSet<i32> as Merge>::take(&mut set);
+    assert!(taken_set.is_some());
+    assert!(set.is_empty());
+
+    let mut vec: Vec<i32> = vec![1];
+    let taken_vec = vec.take();
+    assert!(taken_vec.is_some());
+    assert!(vec.is_empty());
+}
+
+#[test]
+fn test_btree_map_merge_conflict() {
+    let mut map1: BTreeMap<i32, &str> = BTreeMap::new();
+    map1.insert(1, "a");
+    let mut map2: BTreeMap<i32, &str> = BTreeMap::new();
+    map2.insert(1, "b");
+
+    map1.merge(map2);
+
+    assert_eq!(map1.len(), 1);
+    assert_eq!(map1.get(&1), Some(&"b"));
+}
+
+#[test]
+fn test_btree_set_merge_conflict() {
+    let mut set1: BTreeSet<i32> = BTreeSet::new();
+    set1.insert(1);
+    let mut set2: BTreeSet<i32> = BTreeSet::new();
+    set2.insert(1);
+
+    set1.merge(set2);
+
+    assert_eq!(set1.len(), 1);
+    assert!(set1.contains(&1));
+}
+
+#[test]
+fn test_vec_merge_conflict() {
+    let mut vec1 = vec![1, 2, 3];
+    let vec2 = vec![3, 4, 5];
+
+    vec1.merge(vec2);
+
+    assert_eq!(vec1, vec![1, 2, 3, 3, 4, 5]);
+}