GitNexus/.github/scripts/triage/test_embedding_utils.py
2026-03-21 20:06:29 -05:00

337 lines
13 KiB
Python

"""Tests for embedding_utils.py — all embedding model calls are mocked."""
from __future__ import annotations
import sys
from unittest.mock import patch, MagicMock
import numpy as np
import pytest
# Mock fastembed before importing the module under test (persistent)
if "fastembed" not in sys.modules:
sys.modules["fastembed"] = MagicMock()
from embedding_utils import (
embed_texts,
normalize_rows,
reduce_dimensions,
detect_outliers,
find_duplicate_pairs,
suggest_labels,
EMBEDDING_DIM,
EMBEDDING_MODEL,
EMBEDDING_BATCH_SIZE,
LABEL_SIMILARITY_THRESHOLD,
MAX_LABELS_PER_ITEM,
)
class TestEmbedTexts:
"""Tests for the embed_texts function."""
def test_empty_list_returns_empty_array(self):
result = embed_texts([])
assert result.shape == (0, EMBEDDING_DIM)
assert result.dtype == np.float32
@patch("embedding_utils.TextEmbedding")
def test_single_text(self, mock_cls):
mock_model = MagicMock()
mock_cls.return_value = mock_model
vec = np.random.randn(EMBEDDING_DIM).astype(np.float32)
mock_model.embed.return_value = iter([vec])
result = embed_texts(["hello world"])
mock_cls.assert_called_once_with(model_name=EMBEDDING_MODEL)
mock_model.embed.assert_called_once_with(
["hello world"], batch_size=EMBEDDING_BATCH_SIZE
)
assert result.shape == (1, EMBEDDING_DIM)
assert result.dtype == np.float32
np.testing.assert_array_almost_equal(result[0], vec)
@patch("embedding_utils.TextEmbedding")
def test_multiple_texts(self, mock_cls):
mock_model = MagicMock()
mock_cls.return_value = mock_model
vecs = [
np.random.randn(EMBEDDING_DIM).astype(np.float32)
for _ in range(5)
]
mock_model.embed.return_value = iter(vecs)
result = embed_texts(["a", "b", "c", "d", "e"])
assert result.shape == (5, EMBEDDING_DIM)
assert result.dtype == np.float32
class TestNormalizeRows:
"""Tests for L2 row normalization."""
def test_empty_matrix(self):
m = np.empty((0, 10), dtype=np.float32)
result = normalize_rows(m)
assert result.shape == (0, 10)
def test_single_row(self):
m = np.array([[3.0, 4.0]], dtype=np.float32)
result = normalize_rows(m)
# Norm should be ~1.0
norm = np.linalg.norm(result[0])
assert abs(norm - 1.0) < 1e-5
def test_multiple_rows(self):
rng = np.random.default_rng(42)
m = rng.standard_normal((10, 50)).astype(np.float32)
result = normalize_rows(m)
norms = np.linalg.norm(result, axis=1)
np.testing.assert_allclose(norms, 1.0, atol=1e-5)
def test_zero_row_stays_near_zero(self):
m = np.array([[0.0, 0.0, 0.0], [1.0, 0.0, 0.0]], dtype=np.float32)
result = normalize_rows(m)
# Zero row divided by eps -> very small values
assert np.linalg.norm(result[0]) < 1e-3
# Non-zero row should be unit norm
assert abs(np.linalg.norm(result[1]) - 1.0) < 1e-5
def test_preserves_direction(self):
m = np.array([[2.0, 0.0], [0.0, 3.0]], dtype=np.float32)
result = normalize_rows(m)
np.testing.assert_allclose(result[0], [1.0, 0.0], atol=1e-5)
np.testing.assert_allclose(result[1], [0.0, 1.0], atol=1e-5)
class TestReduceDimensions:
"""Tests for PCA dimensionality reduction."""
def test_single_sample_returns_unchanged(self):
m = np.random.randn(1, 50).astype(np.float32)
result = reduce_dimensions(m, 10)
np.testing.assert_array_equal(result, m)
def test_reduces_dimensions(self):
rng = np.random.default_rng(42)
m = rng.standard_normal((100, 50)).astype(np.float32)
result = reduce_dimensions(m, 10)
assert result.shape == (100, 10)
assert result.dtype == np.float32
def test_caps_at_n_minus_1(self):
rng = np.random.default_rng(42)
# 5 samples, 20 features -> max components = 4 (n-1)
m = rng.standard_normal((5, 20)).astype(np.float32)
result = reduce_dimensions(m, 50)
assert result.shape == (5, 4)
def test_caps_at_d(self):
rng = np.random.default_rng(42)
# 100 samples, 3 features -> max components = 3
m = rng.standard_normal((100, 3)).astype(np.float32)
result = reduce_dimensions(m, 50)
assert result.shape == (100, 3)
def test_max_components_respected(self):
rng = np.random.default_rng(42)
m = rng.standard_normal((50, 30)).astype(np.float32)
result = reduce_dimensions(m, 5)
assert result.shape[1] == 5
class TestDetectOutliers:
"""Tests for Mahalanobis-based outlier detection."""
def test_single_sample_returns_empty(self):
m = np.random.randn(1, 5).astype(np.float32)
result = detect_outliers(m, percentile=0.997)
assert result == []
def test_empty_returns_empty(self):
# n < 2 case
m = np.empty((0, 5), dtype=np.float32)
result = detect_outliers(m, percentile=0.997)
assert result == []
def test_finds_outliers_in_synthetic_data(self):
rng = np.random.default_rng(42)
# Create a tight cluster with one obvious outlier
cluster = rng.standard_normal((50, 3)).astype(np.float32) * 0.1
outlier = np.array([[100.0, 100.0, 100.0]], dtype=np.float32)
m = np.vstack([cluster, outlier])
result = detect_outliers(m, percentile=0.997)
# The outlier (index 50) should be detected
outlier_indices = [idx for idx, _ in result]
assert 50 in outlier_indices
def test_returns_list_of_index_distance_tuples(self):
rng = np.random.default_rng(42)
# Tight cluster + outlier to guarantee at least one result
cluster = rng.standard_normal((20, 3)).astype(np.float32) * 0.1
far_point = np.array([[50.0, 50.0, 50.0]], dtype=np.float32)
m = np.vstack([cluster, far_point])
result = detect_outliers(m, percentile=0.997)
assert isinstance(result, list)
for item in result:
assert isinstance(item, tuple)
assert len(item) == 2
idx, dist = item
assert isinstance(idx, int)
assert isinstance(dist, float)
assert dist > 0
def test_low_percentile_flags_more(self):
rng = np.random.default_rng(42)
m = rng.standard_normal((30, 3)).astype(np.float32)
low = detect_outliers(m, percentile=0.5)
high = detect_outliers(m, percentile=0.999)
assert len(low) >= len(high)
def test_dimension_aware_cutoff(self):
"""High-dimensional data should not flag everything with default percentile."""
rng = np.random.default_rng(42)
# 500 samples, 10 dims — well-conditioned for robust covariance
m = rng.standard_normal((500, 10)).astype(np.float32)
result = detect_outliers(m, percentile=0.997)
# With a proper dimension-aware cutoff on clean Gaussian data,
# only a small fraction should be flagged (well under 50%)
assert len(result) < 250
def test_contamination_parameter(self):
rng = np.random.default_rng(42)
m = rng.standard_normal((50, 3)).astype(np.float32)
# Should not raise with different contamination values
result = detect_outliers(m, percentile=0.997, contamination=0.05)
assert isinstance(result, list)
class TestFindDuplicatePairs:
"""Tests for cosine similarity duplicate detection."""
def test_single_item_returns_empty(self):
m = np.random.randn(1, 10).astype(np.float32)
result = find_duplicate_pairs(m, 0.9)
assert result == []
def test_empty_returns_empty(self):
m = np.empty((0, 10), dtype=np.float32)
result = find_duplicate_pairs(m, 0.9)
assert result == []
def test_identical_vectors_detected(self):
vec = np.random.randn(10).astype(np.float32)
vec = vec / np.linalg.norm(vec)
m = np.vstack([vec, vec, np.random.randn(10).astype(np.float32)])
result = find_duplicate_pairs(m, 0.99)
# Items 0 and 1 are identical, should be found
assert any(i == 0 and j == 1 for i, j, _ in result)
def test_orthogonal_vectors_not_detected(self):
m = np.eye(5, dtype=np.float32)
result = find_duplicate_pairs(m, 0.5)
assert result == []
def test_returns_correct_format(self):
vec = np.random.randn(10).astype(np.float32)
vec = vec / np.linalg.norm(vec)
m = np.vstack([vec, vec])
result = find_duplicate_pairs(m, 0.5)
assert len(result) >= 1
for item in result:
assert len(item) == 3
i, j, sim = item
assert isinstance(i, int)
assert isinstance(j, int)
assert isinstance(sim, float)
assert i < j
def test_i_less_than_j(self):
rng = np.random.default_rng(42)
# Create some similar vectors
base = rng.standard_normal(10).astype(np.float32)
m = np.vstack([base + rng.standard_normal(10) * 0.01 for _ in range(5)])
result = find_duplicate_pairs(m, 0.5)
for i, j, _ in result:
assert i < j
def test_high_threshold_fewer_pairs(self):
rng = np.random.default_rng(42)
m = rng.standard_normal((10, 20)).astype(np.float32)
# Normalize for meaningful cosine similarities
norms = np.linalg.norm(m, axis=1, keepdims=True)
m = m / norms
low = find_duplicate_pairs(m, 0.3)
high = find_duplicate_pairs(m, 0.9)
assert len(low) >= len(high)
class TestSuggestLabels:
"""Tests for embedding-based label suggestion."""
def test_empty_items_returns_empty_lists(self):
items = np.empty((0, 10), dtype=np.float32)
labels = np.random.randn(3, 10).astype(np.float32)
result = suggest_labels(items, labels, ["a", "b", "c"])
assert result == []
def test_empty_labels_returns_empty_per_item(self):
items = np.random.randn(5, 10).astype(np.float32)
labels = np.empty((0, 10), dtype=np.float32)
result = suggest_labels(items, labels, [])
assert len(result) == 5
assert all(s == [] for s in result)
def test_identical_embedding_gets_that_label(self):
"""If an item embedding equals a label embedding, it should suggest that label."""
vec = np.array([1.0, 0.0, 0.0], dtype=np.float32)
items = np.array([vec], dtype=np.float32)
labels = np.array([vec, [0, 1, 0], [0, 0, 1]], dtype=np.float32)
result = suggest_labels(items, labels, ["bug", "feature", "docs"], threshold=0.5)
assert len(result) == 1
assert result[0][0][0] == "bug"
assert result[0][0][1] > 0.99
def test_threshold_filters_low_similarity(self):
"""With a high threshold, orthogonal vectors should get no suggestions."""
items = np.eye(3, dtype=np.float32)
labels = np.eye(3, dtype=np.float32)
# threshold=0.99 means only near-exact matches
result = suggest_labels(items, labels, ["a", "b", "c"], threshold=0.99)
# Each item should match exactly one label (itself)
for sugs in result:
assert len(sugs) == 1
def test_max_per_item_respected(self):
"""Even if all labels are similar, max_per_item caps the results."""
rng = np.random.default_rng(42)
base = rng.standard_normal(10).astype(np.float32)
items = np.array([base])
# All labels very similar to item
labels = np.array([base + rng.standard_normal(10) * 0.01 for _ in range(10)])
names = [f"label-{i}" for i in range(10)]
result = suggest_labels(items, labels, names, threshold=0.1, max_per_item=2)
assert len(result[0]) <= 2
def test_returns_sorted_by_similarity_descending(self):
"""Suggestions should be ordered highest similarity first."""
items = np.array([[1.0, 0.5, 0.0]], dtype=np.float32)
labels = np.array([
[1.0, 0.0, 0.0], # decent match
[1.0, 0.5, 0.0], # exact match
[0.0, 0.0, 1.0], # poor match
], dtype=np.float32)
result = suggest_labels(items, labels, ["a", "b", "c"], threshold=0.1)
scores = [s for _, s in result[0]]
assert scores == sorted(scores, reverse=True)
def test_returns_correct_format(self):
rng = np.random.default_rng(42)
items = rng.standard_normal((3, 10)).astype(np.float32)
labels = rng.standard_normal((5, 10)).astype(np.float32)
names = ["bug", "feature", "docs", "ci", "test"]
result = suggest_labels(items, labels, names, threshold=0.0)
assert len(result) == 3
for sugs in result:
for name, score in sugs:
assert isinstance(name, str)
assert isinstance(score, float)
assert name in names