Add tests for CustomContainer

Author: vikahl

tests/test_custom.py

@@ -0,0 +1,25 @@
+from testcontainers.custom import CustomContainer
+
+
+def test_custom_container():
+    """Test that the settings are active on the instance.
+
+    The functionality of spinning up containers are handled by other classes,
+    so only make sure that configuration is set correctly.
+    """
+    image = "google/cloud-sdk:latest"  # Select a suitable image
+    command = "echo 'test'"
+    env = {"ENV1": "VAL1"}
+    name = "my-container"
+    ports = [8080, 8081]
+    volumes = [("/dev/null", "/dev/null2", "ro")]
+
+    with CustomContainer(
+        image=image, command=command, env=env, name=name, ports=ports, volumes=volumes
+    ) as container:
+        assert container.image == image
+        assert container._command == command
+        assert container.env == env
+        assert container._name == name
+        assert list(container.ports.keys()) == ports
+        assert container.volumes == {"/dev/null": {"bind": "/dev/null2", "mode": "ro"}}