From 5edb3c90fbd0492d0654935e2f5d7d9554a9b886 Mon Sep 17 00:00:00 2001
From: "Nelo-T. Wallus" <nelo@wallus.de>
Date: Wed, 17 Jan 2024 10:58:46 +0100
Subject: [PATCH] Support splitting strings on separators

---
 value.go       | 15 ++++++++++++++-
 valueString.go | 30 +++++++++++++++++++++++++++---
 value_test.go  | 37 +++++++++++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/value.go b/value.go
index f4c844e..1871808 100644
--- a/value.go
+++ b/value.go
@@ -153,14 +153,27 @@ func (v Value) To(other any, opts ...ToOption) error {
 
 // List returns the underlying data as a slice of Values.
 //
+// The passed separators are passed to .ListString if the underlying
+// value is a string.
+//
 // Warning: This method is very simplistic and at the moment only
 // returns a proper slice of values if the underlying data is a slice.
-func (v Value) List() ([]Value, error) {
+func (v Value) List(seps ...string) ([]Value, error) {
 	if v.Data == nil {
 		return []Value{}, ErrValueIsNil
 	}
 
 	switch reflect.TypeOf(v.Data).Kind() {
+	case reflect.String:
+		s, err := v.ListString(seps...)
+		if err != nil {
+			return nil, err
+		}
+		vs := make([]Value, len(s))
+		for i := range s {
+			vs[i] = NewValue(s[i])
+		}
+		return vs, nil
 	case reflect.Slice:
 		l := reflect.ValueOf(v.Data)
 		ret := make([]Value, l.Len())
diff --git a/valueString.go b/valueString.go
index df849c6..22bb732 100644
--- a/valueString.go
+++ b/valueString.go
@@ -35,14 +35,21 @@ func (v Value) TrimString() string {
 	return strings.TrimSpace(v.MustString())
 }
 
+// DefaultStringSeparators is used when no separators are passed,
+var DefaultStringSeparators = []string{
+	",",
+	"\n",
+}
+
 // ListString returns the underlying data as a slice of strings.
 //
 // If the underlying data is a slice each member is transformed into
 // a string using the Value.String method.
 //
 // If the underlying data is a string the string is split using the
-// passed separator.
-func (v Value) ListString(sep string) ([]string, error) {
+// passed separator. If not separators are passed
+// DefaultStringSeparators is used.
+func (v Value) ListString(seps ...string) ([]string, error) {
 	val := reflect.ValueOf(v.Data)
 	switch val.Kind() {
 	case reflect.Slice:
@@ -60,7 +67,24 @@ func (v Value) ListString(sep string) ([]string, error) {
 		if err != nil {
 			return nil, fmt.Errorf("dataparse: error turning %q into string to split: %w", v.Data, err)
 		}
-		return strings.Split(s, sep), nil
+
+		if len(seps) == 0 {
+			seps = DefaultStringSeparators
+		}
+
+		for _, sep := range seps {
+			split := strings.Split(s, sep)
+			if len(split) == 1 {
+				// walk through separators until more than one element
+				// is present
+				continue
+			}
+			return split, nil
+		}
+
+		// default to returning the singular element if no separator
+		// split the element.
+		return []string{s}, nil
 	}
 }
 
diff --git a/value_test.go b/value_test.go
index f95b00e..74e2dd5 100644
--- a/value_test.go
+++ b/value_test.go
@@ -170,4 +170,41 @@ func TestValue_List(t *testing.T) {
 		},
 		v,
 	)
+
+	v, err = NewValue("1,2,3").List()
+	assert.Nil(t, err)
+	assert.Equal(t,
+		[]Value{
+			Value{Data: "1"},
+			Value{Data: "2"},
+			Value{Data: "3"},
+		},
+		v,
+	)
+	assert.Equal(t, 1, v[0].MustInt())
+	assert.Equal(t, 2, v[1].MustInt())
+	assert.Equal(t, 3, v[2].MustInt())
+
+	v, err = NewValue("one,two,three").List()
+	assert.Nil(t, err)
+	assert.Equal(t,
+		[]Value{
+			Value{Data: "one"},
+			Value{Data: "two"},
+			Value{Data: "three"},
+		},
+		v,
+	)
+
+	v, err = NewValue("one\ntwo\nthree").List()
+	assert.Nil(t, err)
+	assert.Equal(t,
+		[]Value{
+			Value{Data: "one"},
+			Value{Data: "two"},
+			Value{Data: "three"},
+		},
+		v,
+	)
+
 }