Various ways of testing CDK apps

CDK testing is generally performed in one of two ways:

• Fine-grained assertions: These types of tests are similar to unit testing and are performed to detect regressions. They are conducted with the AWS CDK assertions module (found at https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.assertions-readme.html), which integrates with common testing frameworks such as Jest (https://jestjs.io/) and essentially tests that certain modules in our CDK app have certain properties – for example, a certain EC2 instance will have a specific AMI.
• Snapshot tests: Closer to integration testing, snapshot tests don’t care how you wire up your CDK application. They compare the output of a synthesized CDK stack to a previous state after changes have been applied. Snapshot tests are a great way to refactor your CDK application while making sure the outputs are the same (another way to deal with regression issues).

AWS recommends using...