Thanks for the term "characterisation testing". I started doing this a few years ago while working on a Sphinx extension that defines new directives but also c

Thanks for the term "characterisation testing". I started doing this a few years ago while working on a Sphinx extension that defines new directives but also customizes a few output targets (including two ~plaintext output targets). It's not only useful to avoid accidental output changes, but it's essential for iterating with confidence that tiny changes at the code level affected the output as-expected over a mostly-representative fraction of the documentation set. I didn't have a term for it at the time. I guess about a year later I bumped into snapshot testing, but that's always felt like more of a metaphor.