[skydhash]

Git blame will show the commit and the date for each line. It’s easy to verify if the snippet has changed since the comment. i use Emacs and it’s builtin vc package that color code each block.

[AnimalMuppet]

But you need the snippet and, potentially, the entire call tree (both up and down).

[dullcrisp]

And anything that can affect relevant state, any dependencies that may have changed, validations to input that may have been modified; it’s hard to know without knowing what assumptions the assertion is based on.