test: add test for YouTubeTranscriptsComponent component

src/backend/tests/unit/components/youtube/test_youtube_transcripts_component.py

@@ -0,0 +1,48 @@
+import pytest
+from langflow.components.youtube import YouTubeTranscriptsComponent
+from tests.base import ComponentTestBaseWithClient
+
+
+@pytest.mark.usefixtures("client")
+class TestYouTubeTranscriptsComponent(ComponentTestBaseWithClient):
+    @pytest.fixture
+    def component_class(self):
+        return YouTubeTranscriptsComponent
+
+    @pytest.fixture
+    def default_kwargs(self):
+        return {
+            "url": "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
+            "chunk_size_seconds": 60,
+            "translation": "",
+        }
+
+    @pytest.fixture
+    def file_names_mapping(self):
+        return [
+            {"version": "1.0.0", "module": "youtube_transcripts", "file_name": "YouTubeTranscripts"},
+        ]
+
+    async def test_get_dataframe_output(self, component_class, default_kwargs):
+        component = component_class(**default_kwargs)
+        result = await component.get_dataframe_output()
+        assert result is not None
+        assert isinstance(result, pd.DataFrame)
+        assert "timestamp" in result.data.columns
+        assert "text" in result.data.columns
+
+    async def test_get_message_output(self, component_class, default_kwargs):
+        component = component_class(**default_kwargs)
+        result = await component.get_message_output()
+        assert result is not None
+        assert isinstance(result, Message)
+        assert isinstance(result.text, str)
+
+    async def test_invalid_url(self, component_class):
+        component = component_class(url="invalid_url", chunk_size_seconds=60, translation="")
+        dataframe_result = await component.get_dataframe_output()
+        message_result = await component.get_message_output()
+
+        assert "error" in dataframe_result.data.columns
+        assert "Failed to get YouTube transcripts" in dataframe_result.data["error"].values[0]
+        assert "Failed to get YouTube transcripts" in message_result.text