From 19fb6b77424ea333a634770b5ce4eeffdfbcd1ee Mon Sep 17 00:00:00 2001
From: Green Sky <Green-Sky@users.noreply.github.com>
Date: Tue, 9 Sep 2025 13:48:18 +0200
Subject: [PATCH] keep track of values deletion counts for each actor's

---
 version3/green_crdt/v3/list.hpp | 18 ++++++++++++++++++
 version3/test2.cpp              |  2 ++
 2 files changed, 20 insertions(+)

diff --git a/version3/green_crdt/v3/list.hpp b/version3/green_crdt/v3/list.hpp
index 4db4e8a..21c3af4 100644
--- a/version3/green_crdt/v3/list.hpp
+++ b/version3/green_crdt/v3/list.hpp
@@ -72,6 +72,7 @@ struct List {
 
 	// TODO: actor index instead of map
 	std::unordered_map<size_t, uint64_t> _last_seen_seq;
+	std::unordered_map<size_t, uint64_t> _del_num;
 
 	// caching only, contains the last index an actor inserted at
 	std::unordered_map<size_t, size_t> _last_inserted_idx;
@@ -354,6 +355,7 @@ struct List {
 			if (it.value.has_value()) {
 				it.value.reset();
 
+				_del_num[actor_idx_opt.value()] += 1;
 				_doc_size--;
 				extra_assert(verify());
 				return true;
@@ -404,6 +406,22 @@ struct List {
 		return array;
 	}
 
+	// returns the number of deleted entries for that actor
+	// (not the number the actor deleted!)
+	[[nodiscard]] size_t getDelNum(const ActorType& actor) const {
+		const auto actor_idx_opt = findActor(actor);
+		if (actor_idx_opt.has_value()) {
+			const auto it = _del_num.find(actor_idx_opt.value());
+			if (it != _del_num.cend()) {
+				return it->second;
+			} else {
+				return 0;
+			}
+		} else {
+			return 0;
+		}
+	}
+
 	// TODO: only in debug?
 	bool verify(void) const {
 		if (_list_ids.size() != _list_data.size()) {
diff --git a/version3/test2.cpp b/version3/test2.cpp
index 49bb3b1..d52db9f 100644
--- a/version3/test2.cpp
+++ b/version3/test2.cpp
@@ -156,9 +156,11 @@ Op genDel(Rng& rng, Doc& doc) {
 
 	{
 		auto size_pre = doc.state.getDocSize();
+		const auto num_del_pre = doc.state.getDelNum(op.id.id);
 		bool r = doc.state.del(op.id);
 		assert(r);
 		assert(size_pre-1 == doc.state.getDocSize());
+		assert(num_del_pre+1 == doc.state.getDelNum(op.id.id));
 		assert(doc.state.verify());
 	}