fix: make GreedyEncoder.get_test_params a classmethod

Align GreedyEncoder with skbase estimator testing expectations by making
get_test_params callable on the class. Add a small regression test to ensure
returned parameter sets instantiate and run fit_transform.

Closes #568

Made-with: Cursor

Author: AbinaShah

pyaptamer/trafos/encode/_greedy.py

@@ -132,7 +132,8 @@ def _transform(self, X):
 
         return result_df
 
-    def get_test_params(self):
+    @classmethod
+    def get_test_params(cls, parameter_set="default"):
         """Get test parameters for GreedyEncoder.
 
         Returns

pyaptamer/trafos/encode/tests/__init__.py

@@ -0,0 +1,2 @@
+"""Tests for encoding transformers."""
+

pyaptamer/trafos/encode/tests/test_greedy_encoder.py

@@ -0,0 +1,24 @@
+import inspect
+
+import pandas as pd
+
+from pyaptamer.trafos.encode import GreedyEncoder
+
+
+def test_get_test_params_is_classmethod_and_callable():
+    descriptor = inspect.getattr_static(GreedyEncoder, "get_test_params")
+    assert isinstance(descriptor, classmethod)
+
+    params = GreedyEncoder.get_test_params()
+    assert isinstance(params, list)
+    assert len(params) >= 1
+    assert all(isinstance(p, dict) for p in params)
+
+
+def test_greedy_encoder_can_construct_from_test_params():
+    for params in GreedyEncoder.get_test_params():
+        enc = GreedyEncoder(**params)
+        X = pd.DataFrame([["ACGU"], ["A"]])
+        Xt = enc.fit_transform(X)
+        assert Xt.shape[0] == X.shape[0]
+