Even more validation. (#20762)

* Even more validation.

* Fixing order.

src/transformers/pipelines/text_generation.py

@@ -132,8 +132,12 @@ class TextGenerationPipeline(Pipeline):
         if return_full_text is not None and return_type is None:
             if return_text is not None:
                 raise ValueError("`return_text` is mutually exclusive with `return_full_text`")
+            if return_tensors is not None:
+                raise ValueError("`return_full_text` is mutually exclusive with `return_tensors`")
             return_type = ReturnType.FULL_TEXT if return_full_text else ReturnType.NEW_TEXT
         if return_tensors is not None and return_type is None:
+            if return_text is not None:
+                raise ValueError("`return_text` is mutually exclusive with `return_tensors`")
             return_type = ReturnType.TENSORS
         if return_type is not None:
             postprocess_params["return_type"] = return_type

tests/pipelines/test_pipelines_text_generation.py

@@ -203,6 +203,10 @@ class TextGenerationPipelineTests(unittest.TestCase, metaclass=PipelineTestCaseM
 
         with self.assertRaises(ValueError):
             outputs = text_generator("test", return_full_text=True, return_text=True)
+        with self.assertRaises(ValueError):
+            outputs = text_generator("test", return_full_text=True, return_tensors=True)
+        with self.assertRaises(ValueError):
+            outputs = text_generator("test", return_text=True, return_tensors=True)
 
         # Empty prompt is slighly special
         # it requires BOS token to exist.