TST: Fix flaky test and don't fail fast (#20)

Add `fail-fast` such that all `python` versions will finish
before exiting.

Add `pytest-rerunfailures` for the flaky test.

Fixes: #19
Reviewed-by: @ntessore

.github/workflows/test.yml

@@ -36,15 +36,18 @@ jobs:
     name: Tests
     runs-on: ubuntu-latest
     strategy:
+      fail-fast: false
       matrix:
         python-version: ["3.9", "3.10", "3.11"]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
+          cache: "pip"
+          cache-dependency-path: "pyproject.toml"
       - run: pip install -c .github/test-constraints.txt '.[test]'
-      - run: pytest tests
+      - run: pytest
   build:
     name: Build
     runs-on: ubuntu-latest

pyproject.toml

@@ -37,6 +37,7 @@ optional-dependencies = {docs = [
     "sphinxcontrib-katex",
 ], test = [
     "pytest",
+    "pytest-rerunfailures",
 ]}
 readme = "README.md"
 requires-python = ">=3.9"
@@ -55,6 +56,12 @@ force-exclude = """
 build.hooks.vcs.version-file = "heracles/_version.py"
 version.source = "vcs"
 
+[tool.pytest.ini_options]
+addopts = "--color=yes -v"
+testpaths = [
+    "tests",
+]
+
 [tool.ruff]
 extend-exclude = [
     "_kmeans_radec.py",

tests/test_kmeans_radec.py

@@ -1,3 +1,7 @@
+import pytest
+
+
+@pytest.mark.flaky(reruns=2)
 def test_kmeans_sample():
     import numpy as np