test llm with --no_chat_template (#17785)

.github/workflows/test.yml

@@ -390,10 +390,10 @@ jobs:
         run: |
           parallel --link --tagstring '[{1}]' '{2}' \
             ::: llama 'llama q4' qwen3.5 qwen \
-            ::: $'echo "What\'s a male chicken called? Answer with only one word." | python3 -m tinygrad.llm --model llama3.2:1b | tee /dev/stderr | grep -i rooster' \
-                $'echo "What\'s a male chicken called? Answer with only one word." | python3 -m tinygrad.llm --model llama3.2:1b-q4 | tee /dev/stderr | grep -i rooster' \
-                $'echo "What\'s a male chicken called? Answer with only one word." | python3 -m tinygrad.llm --model qwen3.5:0.8b | tee /dev/stderr | grep -i rooster' \
-                $'echo "What\'s a female chicken called? Answer with only one word." | python3 -m tinygrad.llm --model qwen3:0.6b | tee /dev/stderr | grep -i hen'
+            ::: $'echo "What\'s a male chicken called? Answer with only one word." | python3 -m tinygrad.llm --no_chat_template --model llama3.2:1b | tee /dev/stderr | grep -i rooster' \
+                $'echo "What\'s a male chicken called? Answer with only one word." | python3 -m tinygrad.llm --no_chat_template --model llama3.2:1b-q4 | tee /dev/stderr | grep -i rooster' \
+                $'echo "What\'s a male chicken called? Answer with only one word." | python3 -m tinygrad.llm --no_chat_template --model qwen3.5:0.8b | tee /dev/stderr | grep -i rooster' \
+                $'echo "What\'s a female chicken called? Answer with only one word." | python3 -m tinygrad.llm --no_chat_template --model qwen3:0.6b | tee /dev/stderr | grep -i hen'
                 # NOTE: qwen is dumb and only knows about female chickens
 
 # ****** Models Tests ******

tinygrad/llm/cli.py

@@ -145,6 +145,7 @@ def main():
   parser.add_argument("--serve", nargs='?', type=int, const=8000, metavar="PORT", help="Run OpenAI compatible API (optional port, default 8000)")
   parser.add_argument("--warmup", action="store_true", help="warmup the JIT")
   parser.add_argument("--benchmark", nargs='?', type=int, const=20, metavar="COUNT", help="Benchmark tok/s (optional count, default 20)")
+  parser.add_argument("--no_chat_template", action="store_true", help="Don't use the model's chat template, always use the fallback template")
   args = parser.parse_args()
 
   # load the model
@@ -160,7 +161,7 @@ def main():
 
   # use the model's chat template if jinja2 is available (enables model-specific formatting)
   template: jinja2.Template|FallbackTemplate = FallbackTemplate(tok)
-  if (ct := kv.get('tokenizer.chat_template')) is not None:
+  if not args.no_chat_template and (ct := kv.get('tokenizer.chat_template')) is not None:
     try:
       import jinja2
       env = jinja2.Environment()