tests: Add test for Midi feature

Author: frascuchon

tests/features/test_midi.py

@@ -0,0 +1,77 @@
+import os
+import tempfile
+from unittest import TestCase
+
+import numpy as np
+import pytest
+
+from datasets import Dataset, Features, load_dataset
+from datasets.features import Midi, Value
+
+
+class TestMidiFeature(TestCase):
+    def test_audio_feature_type(self):
+        midi = Midi()
+        assert midi.dtype == "dict"
+        assert midi.pa_type.names == ["bytes", "path"]
+
+    def test_audio_feature_encode_example(self):
+        midi = Midi()
+        
+        # Test with path
+        encoded = midi.encode_example("path/to/midi.mid")
+        assert encoded == {"bytes": None, "path": "path/to/midi.mid"}
+        
+        # Test with bytes
+        encoded = midi.encode_example(b"fake_midi_bytes")
+        assert encoded == {"bytes": b"fake_midi_bytes", "path": None}
+        
+        # Test with dict containing notes
+        notes_data = {
+            "notes": [[60, 64, 0.0, 1.0], [62, 64, 1.0, 2.0]],
+            "tempo": 120.0,
+            "resolution": 480
+        }
+        encoded = midi.encode_example(notes_data)
+        assert "bytes" in encoded
+        assert encoded["path"] is None
+
+    def test_audio_feature_decode_example(self):
+        midi = Midi()
+        
+        # Test decode with bytes
+        fake_midi_bytes = b'MThd\x00\x00\x00\x06\x00\x01\x00\x02\x00\xdcMTrk\x00\x00\x00\x13\x00\xffQ\x03\x07\xa1 \x00\xffX\x04\x04\x02\x18\x08\x01\xff/\x00MTrk\x00\x00\x00\x16\x00\xc0\x00\x00\x90<@\x838<\x00\x00>@\x838>\x00\x01\xff/\x00'
+        decoded = midi.decode_example({"bytes": fake_midi_bytes, "path": None})
+        assert "notes" in decoded
+        assert "tempo" in decoded
+        assert "resolution" in decoded
+        assert "instruments" in decoded
+
+    def test_audio_feature_with_dataset(self):
+        features = Features({"midi": Midi()})
+        data = {"midi": ["fake_path1.mid", "fake_path2.mid"]}
+        
+        with tempfile.TemporaryDirectory() as tmp_dir:
+            dataset = Dataset.from_dict(data, features=features)
+            assert "midi" in dataset.column_names
+            assert dataset.features["midi"].dtype == "dict"
+
+    def test_audio_feature_decode_false(self):
+        midi = Midi(decode=False)
+        encoded = midi.encode_example("path/to/midi.mid")
+        assert encoded == {"bytes": None, "path": "path/to/midi.mid"}
+
+    def test_audio_feature_resolution(self):
+        midi = Midi(resolution=960)
+        assert midi.resolution == 960
+
+    def test_audio_feature_flatten(self):
+        midi = Midi(decode=False)
+        flattened = midi.flatten()
+        assert "bytes" in flattened
+        assert "path" in flattened
+
+    def test_audio_feature_decode_error(self):
+        midi = Midi(decode=False)
+        with pytest.raises(RuntimeError):
+            midi.decode_example({"bytes": b"fake", "path": None})