I have a task to develop a test framework – or a test suite, if it makes more sense – that aims to validate properties over a large set of XML files.

Our codebase is basically like this:

JSON input files -> Python scripts -> XML output files 

Where the Python scripts are responsible for performing complex transformation and calculation rules.

I thought about a couple ways of validating the XML files:

1. Create a set of rules and assert them only on the output files. This one sounds more like a unit test.
2. Perform a validation comparing input and output files. This one sounds more like an integration test.

Do these validations make sense? Am I missing a better way of doing it?