avoid touch go directive and toolchain directive in go.mod

[trim21]

Tell us more.

this is the discussion about #34779

the go itself will touch go directive and toolchain directive, and there are some users(including me) doesn't like this, for example oapi-codegen/oapi-codegen#1641 (comment).

and we have a previously discussion about toolchain directive #34563 and a paritially fix #34564 (comment)

Unfortunately, it still touch directives in these 2 cases:

1. go add toolchain directive when it's missing in the go.mod
2. go update go directive when a package require new go version.

I would suggest to make it possible to preverse go/toolchain directive, disable go automatically updating on it.

[viceice]

What happens to updates which require a go bump?

Worst case is they're silently reverted by go and renovate don't detect it.
I think in those cases renovate suggest the update with an artifact error and ideally doesn't commit the go.sum so ci checks also fail.
A simple artifact error would not block automerge from happening, because it can't be a mandatory status check.

[trim21]

Worst case is they're silently reverted by go and renovate don't detect it.

that PR implements the detection

I think in those cases renovate suggest the update with an artifact error and ideally doesn't commit the go.sum so ci checks also fail.
A simple artifact error would not block automerge from happening, because it can't be a mandatory status check.

Yeah this is the behaviour of that PR