From f5283fb7474818280868b135557c87091243fd6a Mon Sep 17 00:00:00 2001
From: Joao Pedro Henrique <joao.pedro.hsd@gmail.com>
Date: Tue, 24 Oct 2023 00:47:33 -0300
Subject: [PATCH] feat: Add case in which both parents add different nodes

---
 merge/src/lib.rs | 76 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/merge/src/lib.rs b/merge/src/lib.rs
index 41f5f4a..6bd1393 100644
--- a/merge/src/lib.rs
+++ b/merge/src/lib.rs
@@ -148,6 +148,17 @@ pub fn merge(
                         })
                     }
 
+                    cur_left = children_left_it.next();
+                    cur_right = children_right_it.next();
+                } else if !has_matching_base_left
+                    && !has_matching_base_right
+                    && matching_left_right.is_none()
+                {
+                    result_children.push(CSTNode::Conflict {
+                        left: Box::new(Some(cur_left.unwrap().to_owned())),
+                        right: Box::new(Some(cur_right.unwrap().to_owned())),
+                    });
+
                     cur_left = children_left_it.next();
                     cur_right = children_right_it.next();
                 }
@@ -212,6 +223,28 @@ mod tests {
         assert_eq!(expected_merge, merged_tree_swap)
     }
 
+    fn assert_merge_output_is(
+        base: CSTNode,
+        parent_a: CSTNode,
+        parent_b: CSTNode,
+        expected_merge: CSTNode,
+    ) {
+        let matchings_base_parent_a = ordered_tree_matching(&base, &parent_a);
+        let matchings_base_parent_b = ordered_tree_matching(&base, &parent_b);
+        let matchings_parents = ordered_tree_matching(&parent_a, &parent_b);
+
+        let merged_tree = merge(
+            &base,
+            &parent_a,
+            &parent_b,
+            &matchings_base_parent_a,
+            &matchings_base_parent_b,
+            &matchings_parents,
+        );
+
+        assert_eq!(expected_merge, merged_tree);
+    }
+
     #[test]
     fn if_i_am_merging_three_unchanged_nodes_it_is_a_success() {
         let node = CSTNode::Terminal {
@@ -612,4 +645,47 @@ mod tests {
             merged_tree_swap
         );
     }
+
+    #[test]
+    fn if_both_parents_add_different_nodes_then_we_have_a_conflict() {
+        let base = CSTNode::NonTerminal {
+            kind: "kind".into(),
+            children: vec![],
+        };
+
+        let left = CSTNode::NonTerminal {
+            kind: "kind".into(),
+            children: vec![CSTNode::Terminal {
+                kind: "kind_a".into(),
+                value: "value_a".into(),
+            }],
+        };
+
+        let right = CSTNode::NonTerminal {
+            kind: "kind".into(),
+            children: vec![CSTNode::Terminal {
+                kind: "kind_b".into(),
+                value: "value_b".into(),
+            }],
+        };
+
+        assert_merge_output_is(
+            base,
+            left,
+            right,
+            CSTNode::NonTerminal {
+                kind: "kind".into(),
+                children: vec![CSTNode::Conflict {
+                    left: Box::new(Some(CSTNode::Terminal {
+                        kind: "kind_a".into(),
+                        value: "value_a".into(),
+                    })),
+                    right: Box::new(Some(CSTNode::Terminal {
+                        kind: "kind_b".into(),
+                        value: "value_b".into(),
+                    })),
+                }],
+            },
+        )
+    }
 }