refactor(g05): use recipe message dropout

tests/datasets/test_language_render.py

@@ -176,27 +176,19 @@ def test_deterministic_blend_sampling():
     assert first == second
 
 
-def test_applicable_blend_filters_missing_bindings_before_weighted_selection():
+def test_message_dropout_skips_missing_optional_bindings():
     recipe = TrainingRecipe(
-        select_from_applicable=True,
-        blend={
-            "missing": TrainingRecipe(
-                weight=1_000,
-                requires=["subtask"],
-                messages=[
-                    MessageTurn(
-                        role="assistant",
-                        content="${subtask}",
-                        stream="low_level",
-                        target=True,
-                    )
-                ],
+        messages=[
+            MessageTurn(role="user", content="${task}", stream="low_level"),
+            MessageTurn(
+                role="assistant",
+                content="${subtask}",
+                stream="low_level",
+                target=True,
+                if_present="subtask",
+                dropout=0.5,
             ),
-            "action": TrainingRecipe(
-                weight=1,
-                messages=[MessageTurn(role="user", content="${task}", stream="low_level")],
-            ),
-        },
+        ]
     )
 
     rendered = render_sample(
@@ -212,7 +204,7 @@ def test_applicable_blend_filters_missing_bindings_before_weighted_selection():
     assert rendered["target_message_indices"] == []
 
 
-def test_applicable_blend_can_select_joint_bbox_subtask_target():
+def test_g05_dropout_produces_all_bbox_subtask_combinations():
     recipe = TrainingRecipe.from_yaml("src/lerobot/configs/recipes/g05_bbox_subtask.yaml")
     persistent = [persistent_row("assistant", "grasp the cup", "subtask", 0.0)]
     events = [
@@ -224,24 +216,64 @@ def test_applicable_blend_can_select_joint_bbox_subtask_target():
         }
     ]
 
-    rendered = next(
-        candidate
-        for sample_idx in range(100)
-        if (
-            candidate := render_sample(
-                recipe=recipe,
-                persistent=persistent,
-                events=events,
-                t=0.0,
-                sample_idx=sample_idx,
-                task="pick the cup",
-            )
+    rendered_by_targets = {}
+    for sample_idx in range(100):
+        rendered = render_sample(
+            recipe=recipe,
+            persistent=persistent,
+            events=events,
+            t=0.0,
+            sample_idx=sample_idx,
+            task="pick the cup",
         )
-        and candidate["target_message_indices"] == [1, 2]
+        targets = tuple(
+            rendered["messages"][idx]["content"].split(":", 1)[0]
+            for idx in rendered["target_message_indices"]
+        )
+        rendered_by_targets.setdefault(targets, rendered)
+
+    assert set(rendered_by_targets) == {
+        (),
+        ("BBoxJSON",),
+        ("Subtask",),
+        ("BBoxJSON", "Subtask"),
+    }
+    joint = rendered_by_targets[("BBoxJSON", "Subtask")]
+    assert joint["messages"][1]["content"].startswith("BBoxJSON:")
+    assert joint["messages"][2]["content"] == "Subtask: grasp the cup"
+
+
+def test_message_dropout_is_deterministic_for_sample_index():
+    recipe = TrainingRecipe(
+        messages=[
+            MessageTurn(role="user", content="${task}", stream="low_level"),
+            MessageTurn(
+                role="assistant",
+                content="${subtask}",
+                stream="low_level",
+                target=True,
+                dropout=0.5,
+            ),
+        ]
     )
 
-    assert rendered["messages"][1]["content"].startswith("BBoxJSON:")
-    assert rendered["messages"][2]["content"] == "Subtask: grasp the cup"
+    first = render_sample(
+        recipe=recipe,
+        persistent=PERSISTENT,
+        events=[],
+        t=0.0,
+        sample_idx=42,
+        task="pick the cup",
+    )
+    second = render_sample(
+        recipe=recipe,
+        persistent=PERSISTENT,
+        events=[],
+        t=0.0,
+        sample_idx=42,
+        task="pick the cup",
+    )
+    assert first == second
 
 
 def test_emitted_at_filters_vqa_by_camera():