sleepy/llama.cpp
1
0
Fork 0
Code Issues 6 Pull Requests 1 Actions 203 Packages Projects Releases Wiki Activity

common/parser: fix nasty bug causing subtle corruption of generation prompt (#20825)

Browse Source
This commit is contained in:
Piotr Wilkin (ilintar)
2026-03-21 00:19:04 +01:00
committed by GitHub
parent e6ec21e62f
commit b1c70e2e54
4 changed files with 52 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tests/test-chat-auto-parser.cpp
+35
View File
@@ -22,6 +22,7 @@ static void test_calculate_diff_split_no_common(testing & t);
static void test_calculate_diff_split_single_char(testing & t);
static void test_calculate_diff_split_overlaps(testing & t);
static void test_calculate_diff_split_tag_boundaries(testing & t);
static void test_calculate_diff_split_generation_prompt(testing & t);
static void test_calculate_diff_split(testing & t);
static void test_until_common_prefix_basic(testing & t);
@@ -179,6 +180,7 @@ static void test_calculate_diff_split(testing & t) {
t.test("calculate_diff_split single char", test_calculate_diff_split_single_char);
t.test("calculate_diff_split overlaps", test_calculate_diff_split_overlaps);
t.test("calculate_diff_split tag boundaries", test_calculate_diff_split_tag_boundaries);
t.test("calculate_diff_split generation prompt", test_calculate_diff_split_generation_prompt);
}
static void test_calculate_diff_split_basic(testing & t) {
@@ -502,6 +504,39 @@ static void test_calculate_diff_split_tag_boundaries(testing & t) {
}
}
static void test_calculate_diff_split_generation_prompt(testing & t) {
// ChatML thinking template: left is a prefix of right, generation_prompt is the appended part.
// The trailing \n in left matches the trailing \n in the generation_prompt, causing
// the suffix matcher to steal it and rotate the diff result.
{
// Simplified reproduction: left ends with \n, right = left + "<|im_start|>assistant\n<think>\n"
std::string left = "<|im_start|>user\nHello<|im_end|>\n";
std::string right = left + "<|im_start|>assistant\n<think>\n";
diff_split result = calculate_diff_split(left, right);
t.assert_equal("chatml prefix", left, result.prefix);
t.assert_equal("chatml left", "", result.left);
t.assert_equal("chatml right should be generation prompt",
"<|im_start|>assistant\n<think>\n", result.right);
t.assert_equal("chatml suffix", "", result.suffix);
}
{
// More realistic: longer conversation ending with tool_response
std::string common =
"<|im_start|>system\nYou are a helpful assistant.<|im_end|>\n"
"<|im_start|>user\nSearch for files<|im_end|>\n"
"<|im_start|>assistant\n<think>\nLet me search.\n</think>\n\n"
"<tool_call>\n<function=search>\n</function>\n</tool_call><|im_end|>\n"
"<|im_start|>user\n<tool_response>\nNo files found\n</tool_response><|im_end|>\n";
std::string left = common;
std::string right = common + "<|im_start|>assistant\n<think>\n";
diff_split result = calculate_diff_split(left, right);
t.assert_equal("tool_response left", "", result.left);
t.assert_equal("tool_response right should be generation prompt",
"<|im_start|>assistant\n<think>\n", result.right);
}
}
static void test_until_common_prefix(testing & t) {
t.test("until_common_prefix basic", test_until_common_prefix_basic);
}