From 98c74390c086c6a53c7e77d04024e053e5d4b6dd Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Thu, 2 Aug 2018 09:18:31 +0200
Subject: [PATCH] Breaking: Ensure an empty default string does not yield a
 slice with 1 element

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 config.go     |  5 ++++-
 slice_test.go | 12 ++++++++----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/config.go b/config.go
index 251909d..ee9301e 100644
--- a/config.go
+++ b/config.go
@@ -237,7 +237,10 @@ func execTags(in interface{}, fs *pflag.FlagSet) error {
 				if len(del) == 0 {
 					del = ","
 				}
-				def := strings.Split(value, del)
+				var def = []string{}
+				if value != "" {
+					def = strings.Split(value, del)
+				}
 				if len(parts) == 1 {
 					fs.StringSliceVar(valField.Addr().Interface().(*[]string), parts[0], def, typeField.Tag.Get("description"))
 				} else {
diff --git a/slice_test.go b/slice_test.go
index 7d9524e..983f87d 100644
--- a/slice_test.go
+++ b/slice_test.go
@@ -7,10 +7,11 @@ import (
 
 var _ = Describe("Testing slices", func() {
 	type t struct {
-		Int     []int    `default:"1,2,3" flag:"int"`
-		String  []string `default:"a,b,c" flag:"string"`
-		IntP    []int    `default:"1,2,3" flag:"intp,i"`
-		StringP []string `default:"a,b,c" flag:"stringp,s"`
+		Int         []int    `default:"1,2,3" flag:"int"`
+		String      []string `default:"a,b,c" flag:"string"`
+		IntP        []int    `default:"1,2,3" flag:"intp,i"`
+		StringP     []string `default:"a,b,c" flag:"stringp,s"`
+		EmptyString []string `default:""`
 	}
 
 	var (
@@ -48,4 +49,7 @@ var _ = Describe("Testing slices", func() {
 		Expect(len(cfg.StringP)).To(Equal(2))
 		Expect(cfg.StringP).To(Equal([]string{"hallo", "welt"}))
 	})
+	It("should have no elements for an empty default string", func() {
+		Expect(len(cfg.EmptyString)).To(Equal(0))
+	})
 })