Add continuous integration via github actions

.github/workflows/ci.yml

@@ -0,0 +1,67 @@
+name: Continuous integration
+
+on:
+  pull_request:
+    branches:
+      - main
+    types:
+      - opened
+      - reopened
+      - synchronize
+      - ready_for_review
+  push:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ci-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test-pr-not-slow:
+    if: github.event_name == 'pull_request' && !github.event.pull_request.draft
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+          cache: pip
+          cache-dependency-path: pyproject.toml
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e .[dev]
+
+      - name: Run non-slow test suite (PR)
+        run: pytest -m "not slow" -q --durations=10
+
+  test-main-full:
+    if: github.event_name == 'push'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.x'
+          cache: pip
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e .[dev]
+
+      - name: Run full test suite (push to main)
+        run: pytest -q --durations=10

pyproject.toml

@@ -9,7 +9,7 @@ description = "A simple CIPSI (Configuration Interaction with Perturbative Selec
 readme = "README.md"
 license = {text = "MIT"}
 authors = [
-    {name = "J. Philip Haupt"}
+    {name = "Jacobus Philip Haupt"}
 ]
 requires-python = ">=3.9"
 dependencies = [
@@ -34,6 +34,9 @@ testpaths = ["tests"]
 python_files = ["test_*.py"]
 python_classes = ["Test*"]
 python_functions = ["test_*"]
+markers = [
+    "slow: computationally expensive tests excluded from default CI runs",
+]
 
 [tool.black]
 line-length = 100

tests/test_fci_systems.py

@@ -29,12 +29,22 @@
 # ============================================================================
 
 # List of systems to test. Comment out lines to skip specific systems.
-TEST_SYSTEMS = [
+FAST_SYSTEMS = [
     "H2/sto-3g",
     "HeH+/sto-3g",
     "H3+/3-21g",
     "Li/sto-3g",
-    "LiH/6-31gstar",
+]
+
+# systems whose tests take a little longer than desired (> 5 sec on my laptop),
+# to be excluded from CI/CD by default
+SLOW_SYSTEMS = ["LiH/6-31gstar"]
+
+TEST_SYSTEMS = FAST_SYSTEMS + SLOW_SYSTEMS
+
+SYSTEM_DATA_PARAMS = [
+    pytest.param(system, marks=pytest.mark.slow) if system in SLOW_SYSTEMS else system
+    for system in TEST_SYSTEMS
 ]
 
 # Systems small enough (norb=2, 4 FCI dets) for full CIPSI convergence tests.
@@ -108,7 +118,7 @@ def assets_dir():
     return test_dir.parent / "assets"
 
 
-@pytest.fixture(scope="module", params=TEST_SYSTEMS)
+@pytest.fixture(scope="module", params=SYSTEM_DATA_PARAMS)
 def system_data(request, assets_dir):
     """
     Load and cache all data for a test system.