ci: Add GitHub Actions workflow and example test

- Add test.yml workflow that runs on push/PR to main
- Uses PostgreSQL 17 service container
- Runs ruff linting, mypy type checking, and pytest
- Add simple example test demonstrating framework usage
- Example shows transaction isolation between tests

Author: pyramation

.github/workflows/test.yml

@@ -0,0 +1,58 @@
+name: Tests
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    services:
+      postgres:
+        image: postgres:17
+        env:
+          POSTGRES_USER: postgres
+          POSTGRES_PASSWORD: postgres
+          POSTGRES_DB: postgres
+        ports:
+          - 5432:5432
+        options: >-
+          --health-cmd pg_isready
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - name: Install Poetry
+        uses: snok/install-poetry@v1
+        with:
+          version: latest
+          virtualenvs-create: true
+          virtualenvs-in-project: true
+
+      - name: Install dependencies
+        run: poetry install
+
+      - name: Run linting
+        run: poetry run ruff check .
+
+      - name: Run type checking
+        run: poetry run mypy src --ignore-missing-imports
+
+      - name: Run tests
+        env:
+          PGHOST: localhost
+          PGPORT: 5432
+          PGUSER: postgres
+          PGPASSWORD: postgres
+        run: poetry run pytest -v

tests/test_example.py

@@ -0,0 +1,71 @@
+"""
+Simple example test demonstrating pysql-test usage.
+
+This is a minimal example showing how to use the testing framework
+for PostgreSQL integration tests with automatic database isolation.
+"""
+
+import pytest
+
+from pysql_test import get_connections, seed
+
+
+@pytest.fixture
+def db():
+    """
+    Create an isolated test database with sample schema.
+    
+    Each test gets a fresh database that is automatically
+    cleaned up after the test completes.
+    """
+    conn = get_connections(
+        seed_adapters=[
+            seed.fn(lambda ctx: ctx["pg"].query("""
+                CREATE TABLE users (
+                    id SERIAL PRIMARY KEY,
+                    name TEXT NOT NULL,
+                    email TEXT UNIQUE
+                )
+            """))
+        ]
+    )
+    db = conn.db
+    db.before_each()
+    yield db
+    db.after_each()
+    conn.teardown()
+
+
+def test_insert_and_query_user(db):
+    """Test inserting and querying a user."""
+    # Insert a user
+    db.execute(
+        "INSERT INTO users (name, email) VALUES (%s, %s)",
+        ("Alice", "alice@example.com"),
+    )
+
+    # Query the user
+    user = db.one("SELECT * FROM users WHERE name = %s", ("Alice",))
+
+    assert user["name"] == "Alice"
+    assert user["email"] == "alice@example.com"
+
+
+def test_transaction_isolation(db):
+    """Test that changes are rolled back between tests."""
+    # This insert will be rolled back after the test
+    db.execute(
+        "INSERT INTO users (name, email) VALUES (%s, %s)",
+        ("Bob", "bob@example.com"),
+    )
+
+    # Verify the user exists within this test
+    count = db.one("SELECT COUNT(*) as count FROM users")
+    assert count["count"] == 1
+
+
+def test_empty_table_after_rollback(db):
+    """Verify previous test's data was rolled back."""
+    # Table should be empty because previous test's insert was rolled back
+    count = db.one("SELECT COUNT(*) as count FROM users")
+    assert count["count"] == 0