x/tools/cmd/gopls: proposal: provide goimports -local equivalent config

[myitcv]

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

$ go version
go version devel +0cadf40f4c Tue Jul 16 22:31:35 2019 +0000 linux/amd64
$ go list -m golang.org/x/tools
golang.org/x/tools v0.0.0-20190716221150-e98af2309876
$ go list -m golang.org/x/tools/gopls
golang.org/x/tools/gopls v0.1.4-0.20190716221150-e98af2309876

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

go env Output

$ go env
GO111MODULE="on"
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/myitcv/.cache/go-build"
GOENV="/home/myitcv/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/myitcv/gostuff"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/home/myitcv/gos"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/myitcv/gos/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/home/myitcv/gostuff/src/github.com/myitcv/govim/go.mod"
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-build693164838=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Raised originally via govim/govim#385

goimports has a -local flag documented as follows:

  -local string
        put imports beginning with this string after 3rd-party packages; comma-separated list

The proposal here therefore is to provide a []string config option to allow such a list of imports to be provided via editor plugins config options.

cc @stamblerre @ianthehat

[stamblerre]

Duplicate of #32049

[myitcv]

Goodness me, no idea how I missed that other issue. Thanks