chat: fix handling of space in reasoning markers (#22353)

* chat: fix handling of space in reasoning markers

* fix tests

* whitespace

diff --git a/common/chat-diff-analyzer.cpp b/common/chat-diff-analyzer.cpp
index 2f0bd14afa3314c811f62c272ee158abef051094..264ace4627c9c774da99d55187f1adaa1abe31fc 100644 (file)
--- a/common/chat-diff-analyzer.cpp
+++ b/common/chat-diff-analyzer.cpp
@@ -296,7 +296,7 @@ void analyze_reasoning::compare_reasoning_presence() {
             return p.literal(reasoning_content) + p.space() + p.optional(p.tag("post", (p.marker() + p.space())) + p.rest());
         });
         auto parser_wrapped = build_tagged_peg_parser([&](common_peg_parser_builder &p) {
-            return p.tag("pre", p.marker() + p.space()) + p.literal(reasoning_content) + p.space() + p.tag("post", (p.marker() + p.space())) + p.rest();
+            return p.tag("pre", p.marker() + p.space()) + p.literal(reasoning_content) + p.tag("post", (p.space() + p.marker() + p.space())) + p.rest();
         });
         // try the more aggressive parse first, if it fails, fall back to the delimiter one
         auto result = parser_wrapped.parse_anywhere_and_extract(comparison->output_B);
@@ -306,11 +306,11 @@ void analyze_reasoning::compare_reasoning_presence() {
         if (result.result.success()) {
             if (!result.tags["pre"].empty() && !result.tags["post"].empty()) {
                 mode = reasoning_mode::TAG_BASED;
-                start = trim_leading_whitespace(result.tags["pre"]);
-                end   = trim_trailing_whitespace(result.tags["post"]);
+                start = result.tags["pre"];
+                end   = result.tags["post"];
             } else if (!result.tags["post"].empty()) {
                 mode = reasoning_mode::TAG_BASED;
-                end = trim_trailing_whitespace(result.tags["post"]);
+                end = result.tags["post"];
             }
         }
     }

diff --git a/tests/test-chat-auto-parser.cpp b/tests/test-chat-auto-parser.cpp
index bb23b7f2aae4d31a4ed22fe1aa439667ab3c2f15..1d96de718e2ea9b98a8db22e130a282246e0ae4c 100644 (file)
--- a/tests/test-chat-auto-parser.cpp
+++ b/tests/test-chat-auto-parser.cpp
@@ -1331,7 +1331,7 @@ static void test_nemotron_reasoning_detection(testing & t) {
 
     // Check reasoning markers
     t.assert_equal("reasoning_start should be '<think>\\n'", "<think>\n", analysis.reasoning.start);
-    t.assert_equal("reasoning_end should be '</think>'", "</think>", analysis.reasoning.end);
+    t.assert_equal("reasoning_end should be '\\n</think>\\n'", "\n</think>\n", analysis.reasoning.end);
 
     // Check reasoning mode detection
     // Nemotron uses tag-based reasoning; prefill handles the template's forced markers

diff --git a/tests/test-chat.cpp b/tests/test-chat.cpp
index 52b480c24e9a0af9e96ab2495f5a8db7be042bbc..b0545dc954620b4f9e1319a6e8980c386b28033c 100644 (file)
--- a/tests/test-chat.cpp
+++ b/tests/test-chat.cpp
@@ -1642,22 +1642,16 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
         // Qwen3.5 (basically same as Nemotron, but keeping separate tests just in case)
         auto tst = peg_tester("models/templates/Qwen3.5-4B.jinja", detailed_debug);
 
-        tst.test("I'm\nthinking</think>Hello, world!\nWhat's up?")
+        tst.test("I'm\nthinking\n</think>\n\nHello, world!\nWhat's up?")
             .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .enable_thinking(true)
             .expect(message_assist_thoughts)
             .run();
 
-                tst.test("I'm\nthinking\n</think>\nHello, world!\nWhat's up?")
+        tst.test("I'm\nthinking\n</think>\n\nHello, world!\nWhat's up?")
             .enable_thinking(true)
             .reasoning_format(COMMON_REASONING_FORMAT_NONE)
-            .expect_content("<think>\nI'm\nthinking\n</think>\nHello, world!\nWhat's up?")
-            .run();
-
-        tst.test("I'm\nthinking\n</think>\nHello, world!\nWhat's up?")
-            .enable_thinking(true)
-            .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
-            .expect(message_assist_thoughts)
+            .expect_content("<think>\nI'm\nthinking\n</think>\n\nHello, world!\nWhat's up?")
             .run();
 
         tst.test(
@@ -1673,7 +1667,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             .run();
 
         tst.test(
-               "I'm\nthinking\n</think>\n"
+               "I'm\nthinking\n</think>\n\n"
                "<tool_call>\n"
                "<function=special_function>\n"
                "<parameter=arg1>\n1\n</parameter>\n"
@@ -1731,7 +1725,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
 
         tst.test(
                "I need to output the invoice details in JSON\n"
-               "</think>\n"
+               "</think>\n\n"
                R"({"amount": 123.45, "date": "2025-12-03"})")
             .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .enable_thinking(true)
@@ -1751,7 +1745,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
                "hello()\n"
                "</parameter>\n"
                "</function>\n"
-               "</tool_call></think>\n"
+               "</tool_call>\n</think>\n\n"
                "<tool_call>\n"
                "<function=python>\n"
                "<parameter=code>\n"
@@ -1994,7 +1988,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
                "hello()\n"
                "</parameter>\n"
                "</function>\n"
-               "</tool_call></think>\n"
+               "</tool_call>\n</think>\n"
                "<tool_call>\n"
                "<function=python>\n"
                "<parameter=code>\n"
@@ -3463,7 +3457,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             .run();
 
         // Tool call with reasoning (enable_thinking=true)
-        tst.test("I'm\nthinking</think><tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 1}}</tool_call>")
+        tst.test("I'm\nthinking\n</think>\n\n<tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 1}}</tool_call>")
             .enable_thinking(true)
             .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
             .tools({ special_function_tool })
@@ -3487,7 +3481,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             .run();
 
         // Tool call with reasoning and content
-        tst.test("I need to call a function</think>"
+        tst.test("I need to call a function\n</think>\n\n"
                  "Let me check the time.<tool_call>\n{\"name\": \"get_time\", \"arguments\": {\"city\": \"XYZCITY\"}}</tool_call>")
             .enable_thinking(true)
             .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
@@ -3514,7 +3508,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
 
         // fake tool call marker in reasoning
         tst.test(
-               "Let me think about <tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 2}}</tool_call> hmm</think>"
+               "Let me think about <tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 2}}</tool_call> hmm\n</think>\n\n"
                "<tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 1}}</tool_call>")
             .enable_thinking(true)
             .reasoning_format(COMMON_REASONING_FORMAT_AUTO)
@@ -3542,11 +3536,11 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
     // Format: <minimax:tool_call><invoke name="func"><parameter name="key">value</parameter></invoke></minimax:tool_call>
     {
         auto tst = peg_tester("models/templates/MiniMax-M2.jinja", detailed_debug);
-        tst.test("</think>Hello, world!\nWhat's up?").enable_thinking(true).reasoning_format(COMMON_REASONING_FORMAT_AUTO).expect(message_assist).run();
+        tst.test("\n</think>\n\nHello, world!\nWhat's up?").enable_thinking(true).reasoning_format(COMMON_REASONING_FORMAT_AUTO).expect(message_assist).run();
 
-        tst.test("I'm\nthinking</think>Hello, world!\nWhat's up?").enable_thinking(true).reasoning_format(COMMON_REASONING_FORMAT_AUTO).expect(message_assist_thoughts).run();
+        tst.test("I'm\nthinking\n</think>\n\nHello, world!\nWhat's up?").enable_thinking(true).reasoning_format(COMMON_REASONING_FORMAT_AUTO).expect(message_assist_thoughts).run();
 
-        tst.test("Let's call a tool:</think><minimax:tool_call>\n<invoke name=\"empty_args\">\n</invoke>\n</minimax:tool_call>").
+        tst.test("Let's call a tool:\n</think>\n\n<minimax:tool_call>\n<invoke name=\"empty_args\">\n</invoke>\n</minimax:tool_call>").
             enable_thinking(true).
             reasoning_format(COMMON_REASONING_FORMAT_AUTO).
             tools({ empty_args_tool }).
@@ -3554,7 +3548,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             run();
 
         tst.test(
-               "</think><minimax:tool_call>\n<invoke name=\"special_function\">\n<parameter "
+               "\n</think>\n\n<minimax:tool_call>\n<invoke name=\"special_function\">\n<parameter "
                "name=\"arg1\">1</parameter>\n</invoke>\n</minimax:tool_call>")
             .tools({ special_function_tool })
             .expect(message_assist_call)
@@ -3714,7 +3708,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             .enable_thinking(false)
             .expect(message_assist)
             .run();
-        tst.test("I'm\nthinking</think>\n\nHello, world!\nWhat's up?")
+        tst.test("I'm\nthinking\n</think>\n\nHello, world!\nWhat's up?")
             .enable_thinking(true)
             .reasoning_format(COMMON_REASONING_FORMAT_DEEPSEEK)
             .expect(message_assist_thoughts)
@@ -3729,7 +3723,7 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
             .tools({ special_function_tool })
             .expect(message_assist_call_content)
             .run();
-        tst.test("I'm\nthinking</think>\n\n<tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 1}}\n</tool_call>")
+        tst.test("I'm\nthinking\n</think>\n\n<tool_call>\n{\"name\": \"special_function\", \"arguments\": {\"arg1\": 1}}\n</tool_call>")
             .enable_thinking(true)
             .reasoning_format(COMMON_REASONING_FORMAT_DEEPSEEK)
             .tools({ special_function_tool })
@@ -4006,7 +4000,8 @@ static void test_template_output_peg_parsers(bool detailed_debug) {
 
     {
         auto tst = peg_tester("models/templates/StepFun3.5-Flash.jinja", detailed_debug);
-        tst.test("I was thinking</think>\nNow I'm not.").
+
+        tst.test("I was thinking\n</think>\nNow I'm not.").
             enable_thinking(true).
             reasoning_format(COMMON_REASONING_FORMAT_DEEPSEEK).
             expect_reasoning("I was thinking").