Specify go language version

[mxr]

go mirrors are unique in that the module files require a language version. Right now it's hardcoded to 1.19 which EOL'd in 2023 (hmm who chose that version...)

Instead of hardcoding could we make the language version an arg?

[asottile]

isn't that just the minimum version?

[mxr]

For example for i := range 10 { .Println(i) } is a syntax error in go 1.19 but valid in go 1.22+.

So if I want to make a mirror of a library that uses go 1.22+ language features don't I need to specify go 1.22 in go.mod? Or am I misunderstanding what purpose the go.mod serves in the mirror?

[asottile]

I think it's only in the file because the field is required -- technically it would be better to somehow specify it to the version of go but I don't think it actually matters at all https://go.dev/doc/modules/gomod-ref

[mxr]

OK let me try to create a mirror using a go library that uses language constructs unavailable in go 1.19 and see what happens