tests/test_cli.py

# Copyright 2020-2026 The HuggingFace Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import os
from io import StringIO
from unittest.mock import patch

import pytest
import yaml

from .testing_utils import TrlTestCase


@pytest.mark.parametrize("command", ["dpo", "grpo", "kto", "reward", "rloo", "sft"])
def test_help_no_type_error(command):
    # Regression test for https://github.com/huggingface/trl/issues/5099:
    # TrainingArguments help strings with unescaped "%" caused TypeError in argparse.
    from trl.cli import main

    with pytest.raises(SystemExit) as exc_info:
        with patch("sys.argv", ["trl", command, "--help"]), patch("sys.stdout", new_callable=StringIO):
            main()
    assert exc_info.value.code == 0


class TestCLI(TrlTestCase):
    def test_dpo(self):
        from trl.cli import main

        command = f"trl dpo --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_preference --report_to none"
        with patch("sys.argv", command.split(" ")):
            main()

    def test_dpo_multiple_loss_types(self):
        from trl.cli import main

        command = f"trl dpo --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_preference --report_to none --loss_type sigmoid bco_pair --loss_weights 1.0 0.5"
        with patch("sys.argv", command.split(" ")):
            main()

    @patch("sys.stdout", new_callable=StringIO)
    def test_env(self, mock_stdout):
        from trl.cli import main

        command = "trl env"
        with patch("sys.argv", command.split(" ")):
            main()
        assert "TRL version: " in mock_stdout.getvalue().strip()

    def test_grpo(self):
        from trl.cli import main

        command = f"trl grpo --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --reward_model_name_or_path trl-internal-testing/tiny-Qwen2ForSequenceClassification-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_prompt_only --num_generations 4 --max_completion_length 32 --report_to none"
        with patch("sys.argv", command.split(" ")):
            main()

    def test_kto(self):
        from trl.cli import main

        command = f"trl kto --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_unpaired_preference --report_to none"
        with patch("sys.argv", command.split(" ")):
            main()

    def test_reward(self):
        from trl.cli import main

        command = f"trl reward --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_implicit_prompt_preference --report_to none"
        with patch("sys.argv", command.split(" ")):
            main()

    def test_rloo(self):
        from trl.cli import main

        command = f"trl rloo --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --reward_model_name_or_path trl-internal-testing/tiny-Qwen2ForSequenceClassification-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_prompt_only --num_generations 2 --max_completion_length 32 --report_to none"
        with patch("sys.argv", command.split(" ")):
            main()

    def test_sft(self):
        from trl.cli import main

        command = f"trl sft --output_dir {self.tmp_dir} --model_name_or_path trl-internal-testing/tiny-Qwen2ForCausalLM-2.5 --dataset_name trl-internal-testing/zen --dataset_config standard_language_modeling --report_to none"
        with patch("sys.argv", command.split(" ")):
            main()

    def test_sft_config_file(self):
        from trl.cli import main

        output_dir = os.path.join(self.tmp_dir, "output")

        # Create a temporary config file
        config_path = os.path.join(self.tmp_dir, "config.yaml")
        config_content = {
            "model_name_or_path": "trl-internal-testing/tiny-Qwen2ForCausalLM-2.5",
            "dataset_name": "trl-internal-testing/zen",
            "dataset_config": "standard_language_modeling",
            "report_to": "none",
            "output_dir": output_dir,
            "lr_scheduler_type": "cosine_with_restarts",
        }
        with open(config_path, "w") as config_file:
            yaml.dump(config_content, config_file)

        # Test the CLI with config file
        command = f"trl sft --config {config_path}"
        with patch("sys.argv", command.split(" ")):
            main()

        # Verify that output directory was created
        assert os.path.exists(output_dir)

    def test_vllm_serve_config_file(self):
        """
        Test `trl vllm-serve --config config.yaml` must not raise "the following arguments are required: --model" when
        the required field is satisfied by the config file rather than the command line.
        """
        from trl.cli import main

        config_path = os.path.join(self.tmp_dir, "config.yaml")
        with open(config_path, "w") as f:
            yaml.dump({"model": "trl-internal-testing/tiny-Qwen2ForCausalLM-2.5"}, f)

        # Patch the actual function that `VllmServeCommand.run` imports as `vllm_serve_main`
        with patch("trl.scripts.vllm_serve.main") as mock_serve:
            with patch("sys.argv", ["trl", "vllm-serve", "--config", config_path]):
                main()

        mock_serve.assert_called_once()
        script_args = mock_serve.call_args.args[0]
        assert script_args.model == "trl-internal-testing/tiny-Qwen2ForCausalLM-2.5"