Fix TRL_USE_RICH environment variable handling (#1808)

* Add `strtobool` custom implementation from `distutils`

* Fix `TRL_USE_RICH` handling via `strtobool`

* Run `make precommit`

examples/scripts/dpo.py

@@ -55,9 +55,10 @@
 import os
 from contextlib import nullcontext
 
-TRL_USE_RICH = os.environ.get("TRL_USE_RICH", False)
-
 from trl.commands.cli_utils import DPOScriptArguments, init_zero_verbose, TrlParser
+from trl.env_utils import strtobool
+
+TRL_USE_RICH = strtobool(os.getenv("TRL_USE_RICH", "0"))
 
 if TRL_USE_RICH:
     init_zero_verbose()

examples/scripts/sft.py

@@ -51,9 +51,10 @@
 import os
 from contextlib import nullcontext
 
-TRL_USE_RICH = os.environ.get("TRL_USE_RICH", False)
-
 from trl.commands.cli_utils import init_zero_verbose, SFTScriptArguments, TrlParser
+from trl.env_utils import strtobool
+
+TRL_USE_RICH = strtobool(os.getenv("TRL_USE_RICH", "0"))
 
 if TRL_USE_RICH:
     init_zero_verbose()

examples/scripts/vsft_llava.py

@@ -68,9 +68,10 @@
 import os
 from contextlib import nullcontext
 
-TRL_USE_RICH = os.environ.get("TRL_USE_RICH", False)
-
 from trl.commands.cli_utils import init_zero_verbose, SFTScriptArguments, TrlParser
+from trl.env_utils import strtobool
+
+TRL_USE_RICH = strtobool(os.getenv("TRL_USE_RICH", "0"))
 
 if TRL_USE_RICH:
     init_zero_verbose()

trl/commands/cli.py

@@ -41,8 +41,9 @@ def main():
 
         trl_examples_dir = os.path.dirname(__file__)
 
-    # Force-use rich
-    os.environ["TRL_USE_RICH"] = "1"
+    # Force-use rich if the `TRL_USE_RICH` env var is not set
+    if "TRL_USE_RICH" not in os.environ:
+        os.environ["TRL_USE_RICH"] = "1"
 
     if command_name == "chat":
         command = f"""

trl/env_utils.py

@@ -0,0 +1,34 @@
+# Copyright 2022 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.
+#
+# Function `strtobool` copied and adapted from `distutils` (as deprected
+# in Python 3.10).
+# Reference: https://github.com/python/cpython/blob/48f9d3e3faec5faaa4f7c9849fecd27eae4da213/Lib/distutils/util.py#L308-L321
+
+
+def strtobool(val: str) -> bool:
+    """Convert a string representation of truth to True or False booleans.
+
+    True values are 'y', 'yes', 't', 'true', 'on', and '1'; false values
+    are 'n', 'no', 'f', 'false', 'off', and '0'.
+
+    Raises:
+        ValueError: if 'val' is anything else.
+    """
+    val = val.lower()
+    if val in ("y", "yes", "t", "true", "on", "1"):
+        return True
+    if val in ("n", "no", "f", "false", "off", "0"):
+        return False
+    raise ValueError(f"Invalid truth value, it should be a string but {val} was provided instead.")