x/tools/cmd/goimports: goimports should support -s flag for compatibility with gofmt

[eklitzke]

What version of Go are you using (go version)?

$ go version
go version go1.11 linux/amd64

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/evan/.cache/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/evan/go"
GOPROXY=""
GORACE=""
GOROOT="/usr/lib/golang"
GOTMPDIR=""
GOTOOLDIR="/usr/lib/golang/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build466236096=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Tried to use goimports -s

What did you expect to see?

The goimports flag should work with the -s flag, as gofmt does.

What did you see instead?

$ goimports -s
flag provided but not defined: -s

[bradfitz]

We declined this previously in #8759 and updated the docs in golang/tools@7d47e84

It does not aim to be a drop-in replacement. All tools do not need to do all things.