Add script that uses docker to execute some tests

tests/test.py

@@ -0,0 +1,58 @@
+import os
+import docker
+
+
+def test_healthy_package(client, image):
+    print("Testing healthy package...")
+
+    container = client.containers.run(
+        image,
+        volumes={os.getcwd(): {"bind": "/test", "mode": "rw"}},
+        working_dir="/test/healthypkg/",
+        entrypoint="nilaway ./...",
+        detach=True,
+    )
+
+    exit_code = container.wait()
+    logs = container.logs(stdout=True, stderr=True).decode("utf-8")
+    print(exit_code, "\n", logs)
+
+    container.remove()
+
+    assert exit_code["StatusCode"] == 0
+    assert "Potential nil panic detected" not in logs
+
+
+def test_unhealthy_package(client, image):
+    print("Testing unhealthy package...")
+
+    container = client.containers.run(
+        image,
+        volumes={os.getcwd(): {"bind": "/test", "mode": "rw"}},
+        working_dir="/test/unhealthypkg/",
+        entrypoint="nilaway ./...",
+        detach=True,
+    )
+
+    exit_code = container.wait()
+    logs = container.logs(stdout=True, stderr=True).decode("utf-8")
+    print(exit_code, "\n", logs)
+
+    container.remove()
+
+    assert exit_code["StatusCode"] != 0
+    assert "Potential nil panic detected" in logs
+
+
+def main():
+    client = docker.from_env()
+    image, _ = client.images.build(path="../", tag="nilaway-action-test-image")
+
+    test_healthy_package(client, image)
+    test_unhealthy_package(client, image)
+
+    print("All tests passed!")
+
+
+if __name__ == "__main__":
+    main()