path/filepath: filepath.EvalSymlinks returns without error for non-symlink, valid paths

[PrototypeNM1]

My initial assumptions on the nature of the bug were wrong, so the behavior described might be intended (though I did not find clear documentation that the behavior is expected).

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

go version go1.9.2 windows/amd64

Does this issue reproduce with the latest release?

Yes

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

set GOARCH=amd64
set GOBIN=
set GOEXE=.exe
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOOS=windows
set GOPATH=C:\Users\username\go
set GORACE=
set GOROOT=C:\Go
set GOTOOLDIR=C:\Go\pkg\tool\windows_amd64
set GCCGO=gccgo
set CC=gcc
set GOGCCFLAGS=-m64 -mthreads -fmessage-length=0
set CXX=g++
set CGO_ENABLED=1
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config

What did you do?

package main

import (
	"fmt"
	"path/filepath"
)

func main() {
	if path, err := filepath.EvalSymlinks("c:\\Go"); err == nil {
		fmt.Println("Not symlink but no error")
	}
}

What did you expect to see?

Nothing printed as no symlink was provided.

What did you see instead?

Any valid path returns without error.

[mvdan]

EvalSymlinks returns the path name after the evaluation of any symbolic links.

(emphasis mine)

I believe this is by design, and I think that the line above should be clear enough. The godoc can always be extended with clarifications if other people think it's unclear as it is now.

[PrototypeNM1]

This was probably a blind spot in my reading of "evaluation" then; for what it's worth I would have read "resolution" in place of "evaluation" correctly. I'll go ahead and close the issue.