Add extensive language support

tests/processor/test_render_messages_processor.py

@@ -0,0 +1,55 @@
+#!/usr/bin/env python
+
+import torch
+
+from lerobot.configs.recipe import MessageTurn, TrainingRecipe
+from lerobot.processor.converters import create_transition
+from lerobot.processor.render_messages_processor import RenderMessagesStep
+from lerobot.types import TransitionKey
+
+
+def test_render_messages_step_noops_without_language_columns():
+    recipe = TrainingRecipe(
+        messages=[
+            MessageTurn(role="user", content="${task}", stream="high_level"),
+            MessageTurn(role="assistant", content="${subtask}", stream="low_level", target=True),
+        ]
+    )
+    transition = create_transition(complementary_data={"task": "do it"})
+
+    assert RenderMessagesStep(recipe)(transition) == transition
+
+
+def test_render_messages_step_renders_and_drops_raw_language():
+    recipe = TrainingRecipe(
+        messages=[
+            MessageTurn(role="user", content="${task}", stream="high_level"),
+            MessageTurn(role="assistant", content="${subtask}", stream="low_level", target=True),
+        ]
+    )
+    transition = create_transition(
+        complementary_data={
+            "task": "do it",
+            "timestamp": torch.tensor(0.0),
+            "index": torch.tensor(7),
+            "language_persistent": [
+                {
+                    "role": "assistant",
+                    "content": "reach carefully",
+                    "style": "subtask",
+                    "timestamp": 0.0,
+                    "tool_calls": None,
+                }
+            ],
+            "language_events": [],
+        }
+    )
+
+    out = RenderMessagesStep(recipe)(transition)
+    data = out[TransitionKey.COMPLEMENTARY_DATA]
+
+    assert "language_persistent" not in data
+    assert "language_events" not in data
+    assert data["messages"][-1]["content"] == "reach carefully"
+    assert data["message_streams"] == ["high_level", "low_level"]
+    assert data["target_message_indices"] == [1]