allow nested data desc with dots and create the nodes

src/frontend/window/watch_window.cpp

@@ -694,6 +694,9 @@ namespace
 		Frontend *frontend;
 		std::string_view buf;
 		std::vector<char> literal_buf;
+
+		std::optional<WatchToken> peek_token;
+
 		std::string path_buf{};
 		std::vector<data::source::Node> nodes{};
 	};
@@ -742,6 +745,13 @@ namespace
 
 	std::optional<WatchToken> next_token(ParseState &state)
 	{
+		if (state.peek_token)
+		{
+			const auto token = *state.peek_token;
+			state.peek_token.reset();
+			return token;
+		}
+
 		if (state.buf.empty())
 		{
 			spdlog::trace("Token buffer empty");
@@ -783,7 +793,7 @@ namespace
 				state.literal_buf.insert(state.literal_buf.end(), state.buf.begin(),
 				                         literal_end);
 				state.literal_buf.push_back('\0');
-				state.buf.remove_prefix(literal_end - state.buf.begin() + 1);
+				state.buf.remove_prefix(literal_end - state.buf.begin());
 
 				return WatchToken{static_cast<uint32_t>(WatchToken::literal_bit)
 				                  | static_cast<uint32_t>(idx)};
@@ -791,6 +801,24 @@ namespace
 		}
 	}
 
+	std::optional<WatchToken> peek_token(ParseState &state)
+	{
+		if (state.peek_token)
+		{
+			return *state.peek_token;
+		}
+
+		const auto token = next_token(state);
+		if (!token)
+		{
+			return {};
+		}
+
+		state.peek_token = token;
+		return token;
+	}
+
+	// <data desc> = <data desc>.<data desc> | <array desc> | <ident> | <reg>
 	std::optional<size_t> parse_data_desc(ParseState &state)
 	{
 		const auto token_opt = next_token(state);
@@ -803,6 +831,7 @@ namespace
 		spdlog::trace("Parsing data_desc: Token {}", token_to_str(state, token));
 
 		// check for register
+		// <reg> = $<ident>
 		if (token == WatchToken::dollar)
 		{
 			spdlog::trace("Parsing register");
@@ -870,13 +899,73 @@ namespace
 			spdlog::trace("Created register node with id {}", node_id);
 			return node_id;
 		}
+
+		// <data desc>, <array desc> and <ident> expect an identifier now
+		if (!token_is_literal(token))
+		{
+			spdlog::trace("Failed to parse data_desc: expected identifier, got {}",
+			              token_to_str(state, token));
+			return {};
+		}
+
+		const auto ident = token_literal(state, token);
+		spdlog::trace("Parsing data_desc: got ident {}", ident);
+
+		if (!state.path_buf.empty())
+		{
+			state.path_buf.push_back('.');
+		}
+		state.path_buf.append(ident);
+
+		// differentiate between <data desc>, <array desc> and end of <data desc>
+		const auto peek_token_opt = peek_token(state);
+		if (peek_token_opt)
+		{
+			const auto peek_token = *peek_token_opt;
+			spdlog::trace("Parsing data_desc: peek token {}",
+			              token_to_str(state, peek_token));
+			if (peek_token == WatchToken::dot)
+			{
+				// nested <data desc>
+				// consume the token
+				next_token(state);
+				return parse_data_desc(state);
+			}
+
+			if (peek_token == WatchToken::bracket_open)
+			{
+				// TODO: parse <array desc>
+				assert(0);
+				return {};
+			}
+		}
+
+		spdlog::trace("Parsing data_desc: creating variable source with path {}",
+		              state.path_buf);
+		// something else, end of <data desc>
+		auto node_id = state.frontend->target->data_node_id++;
+		state.nodes.push_back(data::source::Node{
+		  .id   = node_id,
+		  .type = data::source::Node::Type::source,
+		  .data =
+		    data::source::Source{
+		      .type = data::source::Source::Type::variable,
+		      .data =
+		        data::source::Source::Variable{
+		          .expr_path             = state.path_buf,
+		          .address_of_or_pointer = false,
+		        },
+		    },
+		});
+
+		return node_id;
 	}
 }  // namespace
 
 void WatchWindow::create_node_for_extra_slot(Frontend &frontend,
                                              const size_t slot_idx)
 {
-	const auto &slot = extra_slots[slot_idx];
+	auto &slot = extra_slots[slot_idx];
 
 	auto parse_state = ParseState{
 	  .frontend    = &frontend,
@@ -884,13 +973,29 @@ void WatchWindow::create_node_for_extra_slot(Frontend &frontend,
 	  .literal_buf = {},
 	};
 
-	assert(0);
+	const auto top_node_id = parse_data_desc(parse_state);
+	if (!top_node_id)
+	{
+		spdlog::warn("Error parsing expression path '{}' for slot {}", slot.buf,
+		             slot_idx);
+		return;
+	}
 
-	using namespace data::source;
-	frontend.target->backend->add_data_node(Node{
-	  .id   = slot.id,
-	  .type = Node::Type::source,
-	  .data = Source{.type = Source::Type::variable,
-	                 .data = Source::Variable{.expr_path             = slot.buf,
-	                                          .address_of_or_pointer = false}}});
+	if (!parse_state.buf.empty())
+	{
+		spdlog::warn(
+		  "Error parsing expression path '{}' for slot {}: trailing data '{}'",
+		  slot.buf, slot_idx, parse_state.buf);
+		return;
+	}
+
+	// TODO: assert node ordering
+
+	for (auto idx = 0; idx < parse_state.nodes.size(); ++idx)
+	{
+		const auto &node = parse_state.nodes[idx];
+		frontend.target->backend->add_data_node(node);
+	}
+
+	slot.id = *top_node_id;
 }