New %S verb causes `go vet` failure in go 1.12.x, not 1.11.x or tip

[theckman]

New %S verb causes `go vet` failure in go 1.12.x, not 1.11.x or tip

[dylan-bourque]

Just tried this w/ Go 1.12.1 on my laptop (Ubuntu 18.04). No error from go vet. 😕

go version -> go version go1.12.1 linux/amd64
go env:

GOARCH="amd64"
GOBIN=""
GOCACHE="/home/dylan/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/dylan/dev/golang"
GOPROXY=""
GORACE=""
GOROOT="/usr/local/go"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS=""
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS=""
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build244704731=/tmp/go-build -gno-record-gcc-switches"

/tmp/test.go:

package main

import (
    "fmt"
    "github.com/gofrs/uuid"
)

func main() {
    u := uuid.Must(uuid.NewV4())
    fmt.Printf("capitalized UUID: %S", u)
}

[dylan-bourque]

Seems to be an issue w/ go vet -> golang/go#31000 (comment)

[dylan-bourque]

Should be fixed in Go 1.21.2 per golang/go#30399

[dylan-bourque]

Apologies for abandoning this. Life happens. ( ._.)

I just verified that go vet is clean when run against the example program @theckman posted above using Go 1.13.1. I don't have an easy way to test against a 1.12 environment.

[cameracker]

This issue appears to have been fixed up stream. Closing for now!