Add curriculum to ab dataset (#345)

* Add curriculum to ab dataset

* Add difficulty to metadata

tests/test_ab.py

@@ -2,7 +2,7 @@ import random
 
 import pytest
 
-from reasoning_gym.algorithmic.ab import ABConfig, ABDataset, compute_steps, generate_program
+from reasoning_gym.algorithmic.ab import ABConfig, ABCurriculum, ABDataset, compute_steps, generate_program
 
 
 def test_ab_config_validation():
@@ -98,3 +98,39 @@ def test_ab_item_structure():
         # Test answer format
         answer_tokens = item["answer"].split()
         assert all(token in ["A#", "#A", "B#", "#B"] for token in answer_tokens)
+
+
+def test_ab_curriculum():
+    """Test the curriculum ab dataset."""
+    curriculum = ABCurriculum()
+    base_value = {"size": 150, "seed": 1}
+
+    base_cfg: ABCurriculum = curriculum.generate_configuration(base_value)
+
+    assert base_cfg.seed == 1
+    assert base_cfg.size == 150
+    assert base_cfg.length == 1
+
+    # Test and validate increase in levels
+    curriculum.increment_attr_level("length")
+    increase_cfg: ABCurriculum = curriculum.generate_configuration(base_value)
+
+    assert increase_cfg.length == 10
+
+    # Test and validate decrease in levels
+    curriculum.decrement_attr_level("length")
+    decrease_cfg: ABCurriculum = curriculum.generate_configuration(base_value)
+
+    assert decrease_cfg.length == 1
+
+    # Test upper bound boundary condition
+    for _ in range(10):
+        curriculum.increment_attr_level("length")
+    upper_bound_cfg: ABCurriculum = curriculum.generate_configuration(base_value)
+    assert upper_bound_cfg.length == 100
+
+    # Test lower bound boundary condition
+    for _ in range(10):
+        curriculum.decrement_attr_level("length")
+    lower_bound_cfg: ABCurriculum = curriculum.generate_configuration(base_value)
+    assert lower_bound_cfg.length == 1