pkg/eval: De-export PwdVariable.

pkg/eval/builtin_ns.go

@@ -90,7 +90,6 @@ var builtinNs = Ns{
 	"true":  vars.NewReadOnly(true),
 	"false": vars.NewReadOnly(false),
 	"paths": NewEnvListVar("PATH"),
-	"pwd":   PwdVariable{},
 	"args":  vars.NewReadOnly(vector.Empty),
 }
 

pkg/eval/eval.go

@@ -172,7 +172,7 @@ func NewEvaler() *Evaler {
 	builtin["num-bg-jobs"] = vars.FromGet(func() interface{} {
 		return strconv.Itoa(ev.state.getNumBgJobs())
 	})
-	builtin["pwd"] = PwdVariable{ev}
+	builtin["pwd"] = NewPwdVar(ev)
 
 	return ev
 }

pkg/eval/pwd.go

@@ -6,20 +6,24 @@ import (
 	"github.com/elves/elvish/pkg/eval/vars"
 )
 
-// PwdVariable is a variable whose value always reflects the current working
+// NewPwdVar returns a variable who value is synchronized with the path of the
+// current working directory.
+func NewPwdVar(ev *Evaler) vars.Var { return pwdVar{ev} }
+
+// pwdVar is a variable whose value always reflects the current working
 // directory. Setting it changes the current working directory.
-type PwdVariable struct {
+type pwdVar struct {
 	ev *Evaler
 }
 
-var _ vars.Var = PwdVariable{}
+var _ vars.Var = pwdVar{}
 
 // Getwd allows for unit test error injection.
 var getwd func() (string, error) = os.Getwd
 
 // Get returns the current working directory. It returns "/unknown/pwd" when
 // it cannot be determined.
-func (PwdVariable) Get() interface{} {
+func (pwdVar) Get() interface{} {
 	pwd, err := getwd()
 	if err != nil {
 		return "/unknown/pwd"
@@ -28,7 +32,7 @@ func (PwdVariable) Get() interface{} {
 }
 
 // Set changes the current working directory.
-func (pwd PwdVariable) Set(v interface{}) error {
+func (pwd pwdVar) Set(v interface{}) error {
 	path, ok := v.(string)
 	if !ok {
 		return ErrPathMustBeString