tests/test_separate.py

from unittest.mock import patch, MagicMock
from pathlib import Path
from separate import separate_vocals_to_mp3


@patch("separate._run_demucs")
@patch("separate._encode_mp3")
def test_separate_returns_mp3_path(mock_encode, mock_demucs, tmp_path):
    audio = tmp_path / "in.m4a"
    audio.write_bytes(b"x")
    no_vocals_wav = tmp_path / "no_vocals.wav"
    no_vocals_wav.write_bytes(b"y")
    mock_demucs.return_value = no_vocals_wav
    out_mp3 = tmp_path / "no_vocals.mp3"
    mock_encode.return_value = out_mp3

    result = separate_vocals_to_mp3(audio)

    assert result == out_mp3
    mock_demucs.assert_called_once_with(audio)
    mock_encode.assert_called_once_with(no_vocals_wav, audio.parent / "no_vocals.mp3")