Generate: text generation pipeline no longer emits max_length warning when it is not set (#23139)

tests/pipelines/test_pipelines_text_generation.py

@@ -14,8 +14,15 @@
 
 import unittest
 
-from transformers import MODEL_FOR_CAUSAL_LM_MAPPING, TF_MODEL_FOR_CAUSAL_LM_MAPPING, TextGenerationPipeline, pipeline
+from transformers import (
+    MODEL_FOR_CAUSAL_LM_MAPPING,
+    TF_MODEL_FOR_CAUSAL_LM_MAPPING,
+    TextGenerationPipeline,
+    logging,
+    pipeline,
+)
 from transformers.testing_utils import (
+    CaptureLogger,
     is_pipeline_test,
     require_accelerate,
     require_tf,
@@ -323,3 +330,26 @@ class TextGenerationPipelineTests(unittest.TestCase):
 
         pipe = pipeline(model="hf-internal-testing/tiny-random-bloom", device_map="auto", torch_dtype=torch.float16)
         pipe("This is a test", do_sample=True, top_p=0.5)
+
+    def test_pipeline_length_setting_warning(self):
+        prompt = """Hello world"""
+        text_generator = pipeline("text-generation", model="hf-internal-testing/tiny-random-gpt2")
+        if text_generator.model.framework == "tf":
+            logger = logging.get_logger("transformers.generation.tf_utils")
+        else:
+            logger = logging.get_logger("transformers.generation.utils")
+        logger_msg = "Both `max_new_tokens`"  # The beggining of the message to be checked in this test
+
+        # Both are set by the user -> log warning
+        with CaptureLogger(logger) as cl:
+            _ = text_generator(prompt, max_length=10, max_new_tokens=1)
+        self.assertIn(logger_msg, cl.out)
+
+        # The user only sets one -> no warning
+        with CaptureLogger(logger) as cl:
+            _ = text_generator(prompt, max_new_tokens=1)
+        self.assertNotIn(logger_msg, cl.out)
+
+        with CaptureLogger(logger) as cl:
+            _ = text_generator(prompt, max_length=10)
+        self.assertNotIn(logger_msg, cl.out)