Man pages matching name go-testfunc in section 7:

go-testfunc.7.en	debian 10 / gccgo-go
go-testfunc.7.en	debian 10 / golang-go
go-testfunc.7.en	debian 11 / gccgo-go
go-testfunc.7.en	debian 11 / golang-go
go-testfunc.7.en	debian 12 / gccgo-go
go-testfunc.7.en	debian 12 / golang-go