llama-stack-mirror/tests/unit/providers/utils/memory/test_reranking.py
Francisco Javier Arceo 8b00883abd feat: Adding OpenAI Compatible Prompts API
Signed-off-by: Francisco Javier Arceo <farceo@redhat.com>
2025-09-04 12:56:32 -04:00

248 lines
10 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
from llama_stack.providers.utils.memory.vector_store import RERANKER_TYPE_RRF, RERANKER_TYPE_WEIGHTED
from llama_stack.providers.utils.vector_io.vector_utils import WeightedInMemoryAggregator
class TestNormalizeScores:
"""Test cases for score normalization."""
def test_normalize_scores_basic(self):
"""Test basic score normalization."""
scores = {"doc1": 10.0, "doc2": 5.0, "doc3": 0.0}
normalized = WeightedInMemoryAggregator._normalize_scores(scores)
assert normalized["doc1"] == 1.0 # Max score
assert normalized["doc3"] == 0.0 # Min score
assert normalized["doc2"] == 0.5 # Middle score
assert all(0 <= score <= 1 for score in normalized.values())
def test_normalize_scores_identical(self):
"""Test normalization when all scores are identical."""
scores = {"doc1": 5.0, "doc2": 5.0, "doc3": 5.0}
normalized = WeightedInMemoryAggregator._normalize_scores(scores)
# All scores should be 1.0 when identical
assert all(score == 1.0 for score in normalized.values())
def test_normalize_scores_empty(self):
"""Test normalization with empty scores."""
scores = {}
normalized = WeightedInMemoryAggregator._normalize_scores(scores)
assert normalized == {}
def test_normalize_scores_single(self):
"""Test normalization with single score."""
scores = {"doc1": 7.5}
normalized = WeightedInMemoryAggregator._normalize_scores(scores)
assert normalized["doc1"] == 1.0
class TestWeightedRerank:
"""Test cases for weighted reranking."""
def test_weighted_rerank_basic(self):
"""Test basic weighted reranking."""
vector_scores = {"doc1": 0.9, "doc2": 0.7, "doc3": 0.5}
keyword_scores = {"doc1": 0.6, "doc2": 0.8, "doc4": 0.9}
combined = WeightedInMemoryAggregator.weighted_rerank(vector_scores, keyword_scores, alpha=0.5)
# Should include all documents
expected_docs = {"doc1", "doc2", "doc3", "doc4"}
assert set(combined.keys()) == expected_docs
# All scores should be between 0 and 1
assert all(0 <= score <= 1 for score in combined.values())
# doc1 appears in both searches, should have higher combined score
assert combined["doc1"] > 0
def test_weighted_rerank_alpha_zero(self):
"""Test weighted reranking with alpha=0 (keyword only)."""
vector_scores = {"doc1": 0.9, "doc2": 0.7, "doc3": 0.5} # All docs present in vector
keyword_scores = {"doc1": 0.1, "doc2": 0.3, "doc3": 0.9} # All docs present in keyword
combined = WeightedInMemoryAggregator.weighted_rerank(vector_scores, keyword_scores, alpha=0.0)
# Alpha=0 means vector scores are ignored, keyword scores dominate
# doc3 should score highest since it has highest keyword score
assert combined["doc3"] > combined["doc2"] > combined["doc1"]
def test_weighted_rerank_alpha_one(self):
"""Test weighted reranking with alpha=1 (vector only)."""
vector_scores = {"doc1": 0.9, "doc2": 0.7, "doc3": 0.5} # All docs present in vector
keyword_scores = {"doc1": 0.1, "doc2": 0.3, "doc3": 0.9} # All docs present in keyword
combined = WeightedInMemoryAggregator.weighted_rerank(vector_scores, keyword_scores, alpha=1.0)
# Alpha=1 means keyword scores are ignored, vector scores dominate
# doc1 should score highest since it has highest vector score
assert combined["doc1"] > combined["doc2"] > combined["doc3"]
def test_weighted_rerank_no_overlap(self):
"""Test weighted reranking with no overlapping documents."""
vector_scores = {"doc1": 0.9, "doc2": 0.7}
keyword_scores = {"doc3": 0.8, "doc4": 0.6}
combined = WeightedInMemoryAggregator.weighted_rerank(vector_scores, keyword_scores, alpha=0.5)
assert len(combined) == 4
# With min-max normalization, lowest scoring docs in each group get 0.0
# but highest scoring docs should get positive scores
assert all(score >= 0 for score in combined.values())
assert combined["doc1"] > 0 # highest vector score
assert combined["doc3"] > 0 # highest keyword score
class TestRRFRerank:
"""Test cases for RRF (Reciprocal Rank Fusion) reranking."""
def test_rrf_rerank_basic(self):
"""Test basic RRF reranking."""
vector_scores = {"doc1": 0.9, "doc2": 0.7, "doc3": 0.5}
keyword_scores = {"doc1": 0.6, "doc2": 0.8, "doc4": 0.9}
combined = WeightedInMemoryAggregator.rrf_rerank(vector_scores, keyword_scores, impact_factor=60.0)
# Should include all documents
expected_docs = {"doc1", "doc2", "doc3", "doc4"}
assert set(combined.keys()) == expected_docs
# All scores should be positive
assert all(score > 0 for score in combined.values())
# Documents appearing in both searches should have higher scores
# doc1 and doc2 appear in both, doc3 and doc4 appear in only one
assert combined["doc1"] > combined["doc3"]
assert combined["doc2"] > combined["doc4"]
def test_rrf_rerank_rank_calculation(self):
"""Test that RRF correctly calculates ranks."""
# Create clear ranking order
vector_scores = {"doc1": 1.0, "doc2": 0.8, "doc3": 0.6} # Ranks: 1, 2, 3
keyword_scores = {"doc1": 0.5, "doc2": 1.0, "doc3": 0.7} # Ranks: 3, 1, 2
combined = WeightedInMemoryAggregator.rrf_rerank(vector_scores, keyword_scores, impact_factor=60.0)
# doc1: rank 1 in vector, rank 3 in keyword
# doc2: rank 2 in vector, rank 1 in keyword
# doc3: rank 3 in vector, rank 2 in keyword
# doc2 should have the highest combined score (ranks 2+1=3)
# followed by doc1 (ranks 1+3=4) and doc3 (ranks 3+2=5)
# Remember: lower rank sum = higher RRF score
assert combined["doc2"] > combined["doc1"] > combined["doc3"]
def test_rrf_rerank_impact_factor(self):
"""Test that impact factor affects RRF scores."""
vector_scores = {"doc1": 0.9, "doc2": 0.7}
keyword_scores = {"doc1": 0.8, "doc2": 0.6}
combined_low = WeightedInMemoryAggregator.rrf_rerank(vector_scores, keyword_scores, impact_factor=10.0)
combined_high = WeightedInMemoryAggregator.rrf_rerank(vector_scores, keyword_scores, impact_factor=100.0)
# Higher impact factor should generally result in lower scores
# (because 1/(k+r) decreases as k increases)
assert combined_low["doc1"] > combined_high["doc1"]
assert combined_low["doc2"] > combined_high["doc2"]
def test_rrf_rerank_missing_documents(self):
"""Test RRF handling of documents missing from one search."""
vector_scores = {"doc1": 0.9, "doc2": 0.7}
keyword_scores = {"doc1": 0.8, "doc3": 0.6}
combined = WeightedInMemoryAggregator.rrf_rerank(vector_scores, keyword_scores, impact_factor=60.0)
# Should include all documents
assert len(combined) == 3
# doc1 appears in both searches, should have highest score
assert combined["doc1"] > combined["doc2"]
assert combined["doc1"] > combined["doc3"]
class TestCombineSearchResults:
"""Test cases for the main combine_search_results function."""
def test_combine_search_results_rrf_default(self):
"""Test combining with RRF as default."""
vector_scores = {"doc1": 0.9, "doc2": 0.7}
keyword_scores = {"doc1": 0.6, "doc3": 0.8}
combined = WeightedInMemoryAggregator.combine_search_results(vector_scores, keyword_scores)
# Should default to RRF
assert len(combined) == 3
assert all(score > 0 for score in combined.values())
def test_combine_search_results_rrf_explicit(self):
"""Test combining with explicit RRF."""
vector_scores = {"doc1": 0.9, "doc2": 0.7}
keyword_scores = {"doc1": 0.6, "doc3": 0.8}
combined = WeightedInMemoryAggregator.combine_search_results(
vector_scores, keyword_scores, reranker_type=RERANKER_TYPE_RRF, reranker_params={"impact_factor": 50.0}
)
assert len(combined) == 3
assert all(score > 0 for score in combined.values())
def test_combine_search_results_weighted(self):
"""Test combining with weighted reranking."""
vector_scores = {"doc1": 0.9, "doc2": 0.7}
keyword_scores = {"doc1": 0.6, "doc3": 0.8}
combined = WeightedInMemoryAggregator.combine_search_results(
vector_scores, keyword_scores, reranker_type=RERANKER_TYPE_WEIGHTED, reranker_params={"alpha": 0.3}
)
assert len(combined) == 3
assert all(0 <= score <= 1 for score in combined.values())
def test_combine_search_results_unknown_type(self):
"""Test combining with unknown reranker type defaults to RRF."""
vector_scores = {"doc1": 0.9}
keyword_scores = {"doc2": 0.8}
combined = WeightedInMemoryAggregator.combine_search_results(
vector_scores, keyword_scores, reranker_type="unknown_type"
)
# Should fall back to RRF
assert len(combined) == 2
assert all(score > 0 for score in combined.values())
def test_combine_search_results_empty_params(self):
"""Test combining with empty parameters."""
vector_scores = {"doc1": 0.9}
keyword_scores = {"doc2": 0.8}
combined = WeightedInMemoryAggregator.combine_search_results(vector_scores, keyword_scores, reranker_params={})
# Should use default parameters
assert len(combined) == 2
assert all(score > 0 for score in combined.values())
def test_combine_search_results_empty_scores(self):
"""Test combining with empty score dictionaries."""
# Test with empty vector scores
combined = WeightedInMemoryAggregator.combine_search_results({}, {"doc1": 0.8})
assert len(combined) == 1
assert combined["doc1"] > 0
# Test with empty keyword scores
combined = WeightedInMemoryAggregator.combine_search_results({"doc1": 0.9}, {})
assert len(combined) == 1
assert combined["doc1"] > 0
# Test with both empty
combined = WeightedInMemoryAggregator.combine_search_results({}, {})
assert len(combined) == 0