As impressive as the tree-sitter ecosystem is, there is a certain danger in building tooling on top of it. Unless tree-sitter is used as the parser in the actual language compiler, it is almost always going to be an approximation to the language grammar. This is somewhat risky if it is important that any kind of semantic analysis, including diffing, is correct. In the case of difftastic, what worries me is that it might be possible to inject malicious code into a repo by exploiting a bug in the tree-sitter grammar/parsing implementation such that the malicious code is hidden from difftastic because, for example, it is treated as whitespace when it actually isn't. This of course wouldn't be a problem if PRs are being handled by github, but what if down the road github starts offering difftastic (or something similar) as a diff option for PRs?

Admittedly, this is a somewhat far fetched scenario that I have posited but I am somewhat concerned that the proliferation of incorrect tree-sitter grammars is going to lead to the worst kind of problem down the road: tools that work great _most_ of the time.