x/tools/cmd/goimports: Spurious newlines

[romeovs]

Please answer these questions before submitting your issue. Thanks!

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

go version go1.8.3 darwin/amd64

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

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/romeo/code/go"
GORACE=""
GOROOT="/usr/local/Cellar/go/1.8.3/libexec"
GOTOOLDIR="/usr/local/Cellar/go/1.8.3/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/ts/5_6bnlvn0lb8g4lnmvh7l9140000gn/T/go-build999961078=/tmp/go-build -gno-record-gcc-switches -fno-common"
CXX="clang++"
CGO_ENABLED="1"
PKG_CONFIG="pkg-config"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"

What did you do?

Using x/tools/goimports does not have a consistent way of grouping imports when newlines are there. For instance, both of these files will not be changed by goimports:

// A.go
package main

import (
	"os"
	"strings"
)

func main() {
	_ := os.Args
	_ := strings.NewReplacer
}

// B.go
package main

import (
	"os"

	"strings"
)

func main() {
	_ := os.Args
	_ := strings.NewReplacer
}

What did you expect to see?

I would expect the second one to be formatted like the first one.

[fraenkel]

This seems like a dupe of #20818

[mvdan]

Indeed a duplicate.

[bradfitz]

@fraenkel, agreed.
Duplicate of #20818

[romeovs]

Weird it did not show up in the GitHub search!
I'll continue the discussion there.