more stuff done, still not diffing

version0/CMakeLists.txt

@@ -5,8 +5,20 @@ project(crdt_version0 CXX C)
 ########################################
 
 add_executable(test1
+	./list.hpp
+	./text_document.hpp
 	./test1.cpp
 )
 
 target_compile_features(test1 PUBLIC cxx_std_17)
 
+########################################
+
+add_executable(test2
+	./list.hpp
+	./text_document.hpp
+	./test2.cpp
+)
+
+target_compile_features(test2 PUBLIC cxx_std_17)
+

version0/test2.cpp

@@ -0,0 +1,222 @@
+#include "./text_document.hpp"
+
+#include <numeric>
+#include <optional>
+#include <random>
+#include <iostream>
+#include <cassert>
+
+// single letter agent, for testing only
+using Agent = char;
+using Doc = GreenCRDT::TextDocument<Agent>;
+using Op = GreenCRDT::TextDocument<Agent>::Op;
+using ListType = Doc::ListType;
+
+// maybe switch it up?
+using Rng = std::minstd_rand;
+
+// 10*7 -> 70 permutations , ggwp
+//               | 1add | 1del | 1rep | 2add | 2del | 2rep | random add | random del | random rep | random
+// empty doc     |      | 0    | 0    |      | 0    | 0    | x          | 0          | 0          |
+// before 1 char |      |      |      |      |      |      |            |            |            |
+// after 1 char  |      |      |      |      |      |      |            |            |            |
+// before 2 char |      |      |      |      |      |      |            |            |            |
+// in 2 char     |      |      |      |      |      |      |            |            |            |
+// after 2 char  |      |      |      |      |      |      |            |            |            |
+// random        |      |      |      |      |      |      |            |            |            |
+
+static const std::vector<char> random_chars {
+	'a', 'b', 'c', 'd', 'e',
+	'f', 'g', 'h', 'i', 'j',
+	'k', 'l', 'm', 'n', 'o',
+	'p', 'q', 'r', 's', 't',
+	'u', 'v', 'w', 'x', 'y',
+	'z',
+
+	'A', 'B', 'C', 'D', 'E',
+	'F', 'G', 'H', 'I', 'J',
+	'K', 'L', 'M', 'N', 'O',
+	'P', 'Q', 'R', 'S', 'T',
+	'U', 'V', 'W', 'X', 'Y',
+	'Z',
+};
+
+std::ostream& operator<<(std::ostream& out, const std::optional<ListType::ListID>& id) {
+	if (id.has_value()) {
+		out << id.value().id << "-" << id.value().seq;
+	} else {
+		out << "null";
+	}
+	return out;
+}
+
+std::ostream& operator<<(std::ostream& out, const ListType::OpAdd& op) {
+	out
+		<< "{ id:" << op.id.id
+		<< "-" << op.id.seq
+		<< ", v:" << op.value
+		<< ", l:" << op.parent_left
+		<< ", r:" << op.parent_right
+		<< " }"
+	;
+	return out;
+}
+
+// genX() changes doc, uses local agent
+
+Op genAdd(Rng& rng, Doc& doc) {
+	ListType::OpAdd op {
+		{doc.local_agent, 0u},
+		std::nullopt,
+		std::nullopt,
+		random_chars[rng()%random_chars.size()]
+	};
+
+	// first id is 0
+	if (doc.state.last_seen_seq.count(doc.local_agent)) {
+		op.id.seq = doc.state.last_seen_seq[doc.local_agent] + 1;
+	}
+
+	if (!doc.state.list.empty()) {
+		// gen parents
+		size_t li = rng()%(1+doc.state.list.size());
+		if (li != doc.state.list.size()) { // nullopt
+			op.parent_left = doc.state.list[li].id;
+		}
+
+		//size_t r_range = 1+doc.state.list.size();
+		//if (li != doc.state.list.size()) {
+			//r_range -= li+1;
+		//}
+		//size_t ri = rng()%r_range;
+		//if (li != doc.state.list.size()) {
+			//ri += li+1;
+		//}
+		//if (ri != doc.state.list.size()) { // nullopt
+			//op.parent_right = doc.state.list[li].id;
+		//}
+
+		if (op.parent_left.has_value()) {
+			if (doc.state.list.size() != li + 1) { // left is not last
+				op.parent_right = doc.state.list[li+1].id;
+			}
+		} else {
+			// left is before first, so right is first
+			op.parent_right = doc.state.list.front().id;
+		}
+	} // else first char, both nullopt
+
+	//std::cout << "op: " << op << "\n";
+
+	{
+		bool r = doc.state.add(op.id, op.value, op.parent_left, op.parent_right);
+		if (!r) {
+			std::cout << "op: " << op << "\n";
+		}
+		assert(r);
+	}
+
+	return op;
+}
+
+//genDel()
+//genRep()
+//genAddContRange()
+//genDelContRange()
+//genRepContRange()
+
+//genRand()
+//genRandRanges()
+std::vector<Op> genRandAll(Rng& rng, Doc& doc) {
+	switch (rng() % 1) {
+		case 0:
+			return {genAdd(rng, doc)};
+	}
+
+	return {};
+}
+
+void testEmptyDocAdds(size_t seed) {
+	Rng rng(seed);
+
+	Doc doc; // empty
+	doc.local_agent = 'A';
+
+	std::string changed_text;
+	{
+		// for modifying
+		Doc doctmp = doc;
+
+		const size_t loop_count = (rng() % 55)+1;
+		for (size_t i = 0; i < loop_count; i++) {
+			genAdd(rng, doctmp);
+		}
+
+		changed_text = doctmp.getText();
+	}
+
+	assert(doc.getText() != changed_text);
+
+	std::cout << "changed_text: " << changed_text << "\n";
+
+	doc.merge(changed_text);
+
+	assert(doc.getText() == changed_text);
+}
+
+void test1CharDocAdds(size_t seed) {
+	Rng rng(seed);
+
+	Doc doc;
+	doc.local_agent = 'A';
+
+	doc.addText(std::nullopt, std::nullopt, "0");
+
+	assert(doc.getText() == "0");
+
+	std::string changed_text;
+	{
+		// for modifying
+		Doc doctmp = doc;
+
+		const size_t loop_count = (rng() % 13)+1;
+		for (size_t i = 0; i < loop_count; i++) {
+			genAdd(rng, doctmp);
+		}
+
+		changed_text = doctmp.getText();
+	}
+
+	assert(doc.getText() != changed_text);
+
+	std::cout << "changed_text: " << changed_text << "\n";
+
+	doc.merge(changed_text);
+
+	assert(doc.getText() == changed_text);
+}
+
+int main(void) {
+	{
+		std::cout << "testEmptyDocAdds:\n";
+		for (size_t i = 0; i < 1'000; i++) {
+			std::cout << "i " << i << "\n";
+			testEmptyDocAdds(1337+i);
+			std::cout << std::string(40, '-') << "\n";
+		}
+		std::cout << std::string(40, '=') << "\n";
+	}
+
+	{
+		std::cout << "test1CharDocAdds:\n";
+		for (size_t i = 0; i < 1'000; i++) {
+			std::cout << "i " << i << "\n";
+			test1CharDocAdds(1337+i);
+			std::cout << std::string(40, '-') << "\n";
+		}
+		std::cout << std::string(40, '=') << "\n";
+	}
+
+	return 0;
+}
+

version0/text_document.hpp

@@ -6,6 +6,8 @@
 #include <variant>
 #include <vector>
 
+#include <iostream> // debug
+
 namespace GreenCRDT {
 
 template<typename AgentType>
@@ -37,14 +39,14 @@ struct TextDocument {
 	}
 
 	static std::vector<Op> text2adds(
-		const AgentType& agent, uint64_t& last_seq,
+		const AgentType& agent, uint64_t seq, // seq is the first seq
 		std::optional<typename ListType::ListID> parent_left,
 		std::optional<typename ListType::ListID> parent_right,
 		std::string_view text
 	) {
 		std::vector<Op> ops;
 		for (size_t i = 0; i < text.size(); i++) {
-			typename ListType::ListID new_id {agent, ++last_seq};
+			typename ListType::ListID new_id {agent, seq++};
 
 			ops.emplace_back(typename ListType::OpAdd{
 				new_id,
@@ -68,7 +70,7 @@ struct TextDocument {
 	) {
 		// TODO: look up typesystem and fix (move? decltype?)
 		std::vector<Op> ops = text2adds(
-			local_agent, state.last_seen_seq[local_agent],
+			local_agent, state.last_seen_seq.count(local_agent) ? state.last_seen_seq[local_agent] : 0u,
 			parent_left,
 			parent_right,
 			text
@@ -77,10 +79,12 @@ struct TextDocument {
 		// TODO: make this better
 		// and apply
 		for (const auto& op : ops) {
-			if constexpr (std::holds_alternative<typename ListType::OpAdd>(op)) {
+			if(std::holds_alternative<typename ListType::OpAdd>(op)) {
 				const auto& add_op = std::get<typename ListType::OpAdd>(op);
-				state.add(add_op.id, add_op.value, add_op.parent_left, add_op.parent_right);
+				//std::cout << "a:" << add_op.id.id << " s:" << add_op.id.seq << " v:" << add_op.value << "\n";
-			} else if constexpr (std::holds_alternative<typename ListType::OpDel>(op)) {
+				bool r = state.add(add_op.id, add_op.value, add_op.parent_left, add_op.parent_right);
+				assert(r);
+			} else if (std::holds_alternative<typename ListType::OpDel>(op)) {
 				const auto& del_op = std::get<typename ListType::OpDel>(op);
 				state.del(del_op.id);
 			} else {
@@ -134,25 +138,95 @@ struct TextDocument {
 
 	// generates ops from the difference
 	// note: rn it only creates 1 diff patch
-	std::vector<Op> merge(std::string_view other_text) {
+	std::vector<Op> merge(std::string_view text) {
-		if (other_text.empty()) {
+		// cases:
+		// - [ ] text is empty
+		// - [x] doc is empty (deep)
+		// - [ ] doc is empty (shallow) // interesting?
+		//
+		// - [x] no changes -> change_start will go through to end
+		//
+		// not at start or end:
+		// - [ ] single char added -> doc.start > doc.end && text.start == text.end -> emit add
+		// - [ ] single char deleted -> doc.start == doc.end && text.start > text.end -> emit del
+		// - [ ] single char replaced -> doc.start == doc.end && text.start == text.end -> emit del, emit add
+		//
+		// - [ ] 2 chars added(together) -> doc.start > doc.end && text.start < text.end -> emit 2add
+		// - [ ] 2 chars deleted(together) -> doc.start < doc.end && text.start > text.end -> emit 2del
+		// - [ ] 2 chars replaced(together) -> doc.start == doc.end && text.start == text.end -> emit 2del, 2add
+
+
+		if (text.empty()) {
+			if (state.list.empty()) {
+				return {};
+			} else {
+				assert(false && "impl me");
 				return {};
 			}
+		}
+		// text not empty
 
 		if (state.list.empty()) {
 			return addText(
 				std::nullopt,
 				std::nullopt,
-				other_text
+				text
 			);
 		}
 
+		// neither empty
+
 		// find start and end of changes
 		// start
-		size_t list_idx_start = 0;
+		size_t list_start = 0;
-		size_t other_idx_start = 0;
+		size_t text_start = 0;
-		//for (; idx_start < state.list.size(); idx_start++) {}
+		bool differ = false;
+		for (; list_start < state.list.size() && text_start < text.size();) {
+			// jump over tombstones
+			if (!state.list[list_start].value.has_value()) {
+				list_start++;
+				continue;
+			}
 
+			if (state.list[list_start].value != text[text_start]) {
+				differ = true;
+				break;
+			}
+
+			list_start++;
+			text_start++;
+		}
+
+		// doc and text dont differ
+		if (!differ) {
+			return {};
+		}
+
+		std::cout << "list.size: " << state.list.size() << "(" << getText().size() << ")" << " text.size: " << text.size() << "\n";
+		std::cout << "list_start: " << list_start << " text_start: " << text_start << "\n";
+
+		// +1 so i can have unsigned
+		size_t list_end = state.list.size();
+		size_t text_end = text.size();
+		for (; list_end > 0 && text_end > 0 && list_end >= list_start && text_end >= text_start;) {
+			// jump over tombstones
+			if (!state.list[list_end-1].value.has_value()) {
+				list_end--;
+				continue;
+			}
+
+			if (state.list[list_end-1].value.value() != text[text_end-1]) {
+				break;
+			}
+
+			list_end--;
+			text_end--;
+		}
+
+		std::cout << "list_end: " << list_end << " text_end: " << text_end << "\n";
+
+		assert(false && "implement me");
+		return {};
 	}
 };