support rsplit

[f291400]

No description provided.

[f291400]

@ochafik please check again

[ochafik]

Hi @f291400 , thanks for opening this PR

The tests seem to cover something different than rsplit. Can you drop those changes and add a test for rsplit in test-syntax, and also mention in which template you've seen this? (if this unlock a new template, can you add it to the tested model ids in tests/CMakeLists.txt ?)

As for the thinking tests, I'm preparing an overhaul of thinking patterns in templates and their testing, stay tuned!

[f291400]

@ochafik Currently, none of the open-source large language models use rsplit; this is used in the custom YouTu-LLM model, which will be open-sourced soon.
I just deleted the relevant test code， please check it again.

[f291400]

Could you kindly review the current submission?

[CISC]

@ochafik gentle ping

[CISC]

Suggested change

	int splits = 0;
	while (end != std::string::npos && (maxsplit < 0 || splits < maxsplit)) {
	result.push_back(s.substr(start, end - start));
	start = end + sep.length();
	end = s.find(sep, start);
	splits++;
	while (end != std::string::npos && maxsplit != 0) {
	result.push_back(s.substr(start, end - start));
	start = end + sep.length();
	end = s.find(sep, start);
	--maxsplit;

[CISC]

Suggested change

	int splits = 0;
	while (pos != std::string::npos && (maxsplit < 0 || splits < maxsplit)) {
	result.insert(result.begin(), s.substr(pos + sep.length(), end - pos - sep.length()));
	end = pos;
	splits++;
	if (pos == 0) break;
	pos = s.rfind(sep, pos - 1);
	}
	result.insert(result.begin(), s.substr(0, end));
	while (pos != std::string::npos && maxsplit != 0) {
	result.push_back(s.substr(pos + sep.length(), end - pos - sep.length()));
	end = pos;
	--maxsplit;
	if (pos == 0) break;
	pos = s.rfind(sep, pos - 1);
	}
	result.push_back(s.substr(0, end));
	std::reverse(result.begin(), result.end());

[CISC]

Suggested change

	if (start == std::string::npos) return "";
	if (start == std::string::npos) return "";