Repository: ggml-org/llama.cpp
Pull request: common : add reasoning_format = none support to gpt-oss

## Overview

Add `reasoning_format = none` support to gpt-oss.

ref: https://github.com/ggml-org/llama.cpp/pull/20393#issuecomment-4095000092

# Requirements

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- AI usage disclosure: NO

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Changed files:
filename: common/chat.cpp
patch: @@ -971,6 +971,7 @@ static common_chat_params common_chat_params_init_gpt_oss(const common_chat_temp
     auto has_tools           = inputs.tools.is_array() && !inputs.tools.empty();
     auto has_response_format = !inputs.json_schema.is_null() && inputs.json_schema.is_object();
     auto include_grammar     = has_response_format || (has_tools && inputs.tool_choice != COMMON_CHAT_TOOL_CHOICE_NONE);
+    auto extract_reasoning   = inputs.reasoning_format != COMMON_REASONING_FORMAT_NONE;
 
     auto parser = build_chat_peg_parser([&](common_chat_peg_builder & p) {
         auto start           = p.rule("start", p.literal("
assistant"));
@@ -979,7 +980,13 @@ static common_chat_params common_chat_params_init_gpt_oss(const common_chat_temp
         auto channel         = p.literal("
") + (p.literal("commentary") | p.literal("analysis"));
         auto constrain_type  = p.chars("[A-Za-z0-9_-]", 1, -1);
 
-        auto analysis = p.rule("analysis", p.literal("
analysis
") + p.reasoning(content) + end);
+        if (extract_reasoning) {
+            p.rule("analysis", p.literal("
analysis
") + p.reasoning(content) + end);
+        } else {
+            p.rule("analysis", p.content(p.literal("
analysis
") + content + end));
+        }
+
+        auto analysis = p.ref("analysis");
         auto preamble = p.rule("preamble", p.literal("
commentary
") + p.content(content) + end);
         auto final_msg = p.rule("final", p.literal("
final
") + p.content(content));
         auto any = p.rule("any", preamble | analysis);

filename: tests/test-chat.cpp
patch: @@ -2796,6 +2796,14 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             .expect(message_assist_thoughts)
             .run();
 
+        // Analysis channel (reasoning) with final channel (content) with reasoning_format = none
+        tst.test(
+               "
analysis
I'm\nthinking

assistant
final
Hello, world!\nWhat's "
+               "up?")
+            .reasoning_format(COMMON_REASONING_FORMAT_NONE)
+            .expect_content("
analysis
I'm\nthinking
Hello, world!\nWhat's up?")
+            .run();
+
         // Analysis channel only (partial) - still works when reasoning format is set
         tst.test("
analysis
I'm\nthinking")
             .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
@@ -2805,24 +2813,28 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
 
         // Tool call with recipient in role header: " to=functions.NAME
analysis
JSON"
         tst.test(" to=functions.special_function
analysis
{\"arg1\": 1}")
+            .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .tools({ special_function_tool })
             .expect(message_assist_call)
             .run();
 
         // Tool call with recipient in channel header: "
analysis to=functions.NAME
JSON"
         tst.test("
analysis to=functions.special_function
{\"arg1\": 1}")
+            .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .tools({ special_function_tool })
             .expect(message_assist_call)
             .run();
 
         // Tool call with constraint: " to=functions.NAME
analysis 
json
JSON"
         tst.test(" to=functions.special_function
analysis 
json
{\"arg1\": 1}")
+            .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .tools({ special_function_tool })
             .expect(message_assist_call)
             .run();
 
         // Tool call in commentary channel (channel header variant)
         tst.test("
commentary to=functions.special_function
{\"arg1\": 1}")
+            .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .tools({ special_function_tool })
             .expect(message_assist_call)
             .run();