I realize that rule arguments are used to invalidate a rule, but how about Get requests executed during a rule body, if any of those dependent rules are invalidated does that also invalidate the first rule? Example will probably do a better job at illustrating what I’m asking:

rule R(A, B) -> Get(Environment, EnvironmentRequest(X)) -> Result

now, if the value for

X

changes, does that invalidate rule

R

too?

e.g. the

Get

request is the same, it would only be the resulting environment response that has a changed value.

thus changes will cause rule invalidation

the Pants engine actually parses the source of the rule and extracts

Get

instances in order to do that registration

see

src/python/pants/engine/internals/rule_visitor.py

for details of the source parsing

still a bit fuzzy for me how the actual values for these edges affect invalidation/caching..

🤔 guess only inputs can affect caching, as the return value would only ever be the case when requested by a rule being evaluated, so the return value will be consumed regardless… OK, I think that makes more sense to me now. Thanks Tom!