How to test docker image with external script

Assume that I have a code repo. That code repo has the following files in it:

• Dockerfile
• test.sh

lets say I now build a docker image from the Dockerfile

docker build -t my-image .

Now I want to execute the test.sh in the context of my-image in a container, yet I don't have added test.sh to the docker image during build.

How do I run the docker image and execute the test.sh in it? Do I have to mount the repo as volume first or is there a quicker way?