chore: import upstream snapshot with attribution

tests/cli/test_chat.py

@@ -0,0 +1,46 @@
+# Copyright 2025 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 json
+import os
+import tempfile
+
+from transformers.cli.chat import new_chat_history, parse_generate_flags, save_chat
+
+
+def test_help(cli):
+    output = cli("chat", "--help")
+    assert output.exit_code == 0
+    assert "Chat with a model from the command line." in output.output
+
+
+def test_save_and_clear_chat():
+    with tempfile.TemporaryDirectory() as tmp_path:
+        filename = os.path.join(tmp_path, "chat.json")
+        save_chat(filename, [{"role": "user", "content": "hi"}], {"foo": "bar"})
+        assert os.path.isfile(filename)
+        with open(filename, "r") as f:
+            data = json.load(f)
+            assert data["chat_history"] == [{"role": "user", "content": "hi"}]
+            assert data["settings"] == {"foo": "bar"}
+
+
+def test_new_chat_history():
+    assert new_chat_history() == []
+    assert new_chat_history("prompt") == [{"role": "system", "content": "prompt"}]
+
+
+def test_parse_generate_flags():
+    parsed = parse_generate_flags(["temperature=0.5", "max_new_tokens=10"])
+    assert parsed["temperature"] == 0.5
+    assert parsed["max_new_tokens"] == 10