helper/args: variadic check function

This package turns out to be much less widely used than anticipated, and might be facing removal. This change makes test cases cleaner.

Signed-off-by: Ophestra <cat@gensokyo.uk>

helper/args.go

@@ -35,7 +35,7 @@ func (a argsWt) String() string {
 }
 
 // NewCheckedArgs returns a checked null-terminated argument writer for a copy of args.
-func NewCheckedArgs(args []string) (wt io.WriterTo, err error) {
+func NewCheckedArgs(args ...string) (wt io.WriterTo, err error) {
 	a := make(argsWt, len(args))
 	for i, arg := range args {
 		a[i], err = syscall.ByteSliceFromString(arg)
@@ -49,8 +49,8 @@ func NewCheckedArgs(args []string) (wt io.WriterTo, err error) {
 
 // MustNewCheckedArgs returns a checked null-terminated argument writer for a copy of args.
 // If s contains a NUL byte this function panics instead of returning an error.
-func MustNewCheckedArgs(args []string) io.WriterTo {
-	a, err := NewCheckedArgs(args)
+func MustNewCheckedArgs(args ...string) io.WriterTo {
+	a, err := NewCheckedArgs(args...)
 	if err != nil {
 		panic(err.Error())
 	}

helper/args_test.go

@@ -22,7 +22,7 @@ func TestNewCheckedArgs(t *testing.T) {
 	t.Parallel()
 
 	args := []string{"\x00"}
-	if _, err := helper.NewCheckedArgs(args); !errors.Is(err, syscall.EINVAL) {
+	if _, err := helper.NewCheckedArgs(args...); !errors.Is(err, syscall.EINVAL) {
 		t.Errorf("NewCheckedArgs: error = %v, wantErr %v", err, syscall.EINVAL)
 	}
 
@@ -36,6 +36,6 @@ func TestNewCheckedArgs(t *testing.T) {
 				t.Errorf("MustNewCheckedArgs: panic = %v, wantPanic %v", r, wantPanic)
 			}
 		}()
-		helper.MustNewCheckedArgs(badPayload)
+		helper.MustNewCheckedArgs(badPayload...)
 	})
 }

helper/helper_test.go

@@ -27,7 +27,7 @@ var (
 	}
 
 	wantPayload = strings.Join(wantArgs, "\x00") + "\x00"
-	argsWt      = helper.MustNewCheckedArgs(wantArgs)
+	argsWt      = helper.MustNewCheckedArgs(wantArgs...)
 )
 
 func argF(argsFd, statFd int) []string {