from unittest.mock import MagicMock, patch
import pytest
from src.core.settings import RerankSettings, Settings
from src.libs.reranker.base_reranker import BaseReranker
from src.libs.reranker.cross_encoder_reranker import CrossEncoderReranker
from src.libs.reranker.llm_reranker import LLMReranker
from src.libs.reranker.reranker_factory import NoneReranker, RerankerFactory
@pytest.fixture
def mock_settings():
settings = MagicMock(spec=Settings)
settings.rerank = MagicMock(spec=RerankSettings)
return settings
def test_none_reranker_behavior():
"""Test that NoneReranker returns candidates unchanged."""
reranker = NoneReranker()
candidates = ["doc1", "doc2", "doc3"]
query = "test query"
# Without top_k
results = reranker.rerank(query, candidates)
assert results == candidates
# With top_k
results_top_2 = reranker.rerank(query, candidates, top_k=2)
assert results_top_2 == ["doc1", "doc2"]
assert len(results_top_2) == 2
def test_factory_create_none_reranker(mock_settings):
"""Test factory creates NoneReranker when backend is 'none'."""
mock_settings.rerank.backend = "none"
reranker = RerankerFactory.create(mock_settings)
assert isinstance(reranker, NoneReranker)
assert isinstance(reranker, BaseReranker)
def test_factory_unsupported_backend(mock_settings):
"""Test factory raises ValueError for unknown backend."""
mock_settings.rerank.backend = "unknown_bert"
with pytest.raises(ValueError, match="Unsupported reranker backend"):
RerankerFactory.create(mock_settings)
def test_factory_case_insensitive(mock_settings):
"""Test factory handles backend case insensitively."""
mock_settings.rerank.backend = "NONE"
reranker = RerankerFactory.create(mock_settings)
assert isinstance(reranker, NoneReranker)
@patch("src.libs.reranker.reranker_factory.LLMFactory")
def test_factory_create_llm_reranker(mock_llm_factory, mock_settings):
"""Test factory creates LLMReranker when backend is 'llm'."""
mock_settings.rerank.backend = "llm"
# Mock LLM creation
mock_llm = MagicMock()
mock_llm_factory.create.return_value = mock_llm
reranker = RerankerFactory.create(mock_settings)
assert isinstance(reranker, LLMReranker)
assert reranker.llm == mock_llm
mock_llm_factory.create.assert_called_once_with(mock_settings)
@patch("src.libs.reranker.cross_encoder_reranker.CrossEncoderReranker._load_model")
def test_factory_create_cross_encoder_reranker(mock_load_model, mock_settings):
"""Test factory creates CrossEncoderReranker when backend is 'cross-encoder'."""
mock_settings.rerank.backend = "cross-encoder"
mock_settings.rerank.model = "test/model"
reranker = RerankerFactory.create(mock_settings)
assert isinstance(reranker, CrossEncoderReranker)
assert reranker.model_name == "test/model"
def test_none_reranker_boundaries():
"""Test NoneReranker with boundary conditions."""
reranker = NoneReranker()
query = "test"
# 1. Empty candidates
assert reranker.rerank(query, []) == []
# 2. Candidates fewer than top_k
candidates = ["a", "b"]
assert len(reranker.rerank(query, candidates, top_k=10)) == 2
# 3. Candidates equal to top_k
assert len(reranker.rerank(query, candidates, top_k=2)) == 2
# 4. Top_k=0 (should return empty list)
assert reranker.rerank(query, candidates, top_k=0) == []
# 5. Very large input (should work fast for NoneReranker)
large_candidates = ["doc"] * 100
assert len(reranker.rerank(query, large_candidates, top_k=50)) == 50
