go/format: Struct literal alignment differing between 1.10 and 1.11beta1

[jacobbednarz]

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

go1.11beta1

Does this issue reproduce with the latest release?

Yes - it appears to only be present in the latest beta release.

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

go env output: https://travis-ci.org/cloudflare/cloudflare-go/jobs/397558038#L444

GOARCH="amd64"
GOBIN=""
GOCACHE="/home/travis/.cache/go-build"
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/travis/gopath"
GOPROXY=""
GORACE=""
GOROOT="/home/travis/.gimme/versions/go1.11beta1.linux.amd64"
GOTMPDIR=""
GOTOOLDIR="/home/travis/.gimme/versions/go1.11beta1.linux.amd64/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
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-build714400769=/tmp/go-build -gno-record-gcc-switches"

What did you do?

Playground link: https://play.golang.org/p/ccTd61RjEgE (renders go fmt correctly)

What did you expect to see?

package main

import (
	"fmt"
)

type MyStruct struct {
	Test                                    string
	Test1                                   string
	Test2                                   string
	MyReallyLongKeyThatNoOneShouldAlignWith string
}

func main() {
	var myVar = MyStruct{
		Test:  "this is my string",
		Test1: "test1",
		Test2: "test2",
		MyReallyLongKeyThatNoOneShouldAlignWith: "also a string",
	}
	fmt.Println(myVar)
}

What did you see instead?

Failed CI step demonstrating this on beta1 wanting the file to be formatted as below.

package main

import (
	"fmt"
)

type MyStruct struct {
	Test                                    string
	Test1                                   string
	Test2                                   string
	MyReallyLongKeyThatNoOneShouldAlignWith string
}

func main() {
	var myVar = MyStruct{
		Test:                                    "this is my string",
		Test1:                                   "test1",
		Test2:                                   "test2",
		MyReallyLongKeyThatNoOneShouldAlignWith: "also a string",
	}
	fmt.Println(myVar)
}

Full failed step details: https://travis-ci.org/cloudflare/cloudflare-go/jobs/397558038#L498

[ianlancetaylor]

CC @griesemer to check that this is an intentional change.

[griesemer]

Yes, this was an intentional change (commit 542ea5a). See that change for justification.

[jacobbednarz]

Awesome stuff! Thanks a bunch for a speedy response and great commit overview of the change!