Handle iterators introduced in Go 1.23

[yuxincs]

Go 1.23 introduced iterators, which NilAway does not support yet. This issue tracks such support.

Initially, we should at least assume these are deeply nonnil without panicking.

[spacewander]

Is there someone still working on this issue? Currently, nilaway can't work with programs written with Go 1.23.

[yuxincs]

Hey @spacewander , could you share the logs for "nilaway can't work with programs written with Go 1.23"?

We had a PR landed to at least not panicking for iterators, and we assume the results from the iterators are always non-nil (such that it can lead to false negatives), but it should be working fine for other patterns.

[spacewander]

Glad to hear that there is an ongoing PR addresses this issue!
Sorry for my previous words. In my situation, an APP has been migrated to Go 1.23, and after introducing the iterators feature, the nilaway won't work anymore. Would give a try once the PR is merged. Could you tell me which PR is solving this issue so that I could subscribe to it?

[yuxincs]

It is actually already merged #288, could you verify that you're on the latest version?

Also, when you say "won't work anymore", could you clarify it a bit? Does it show some errors (panics), or does it simply stop reporting previously-reported diagnostics? 🤔

[spacewander]

I got some messages about iter when running nilaway with a project configured with Go 1.23:

.../pkg/mod/golang.org/[email protected]/src/slices/iter.go:50:17: cannot range over seq (variable of type iter.Seq[E])
.../pkg/mod/golang.org/[email protected]/src/maps/iter.go:51:20: cannot range over seq (variable of type iter.Seq2[K, V])
.../pkg/mod/golang.org/x/[email protected]/html/iter.go:50:17: cannot range over n.ChildNodes() (value of type iter.Seq[*Node])

Not sure if it is related.