fix: panic when calling SegmentationUPID.ASCIIValue (#36)

pkg/scte35/segmentation_upid.go

@@ -170,7 +170,7 @@ func (upid *SegmentationUPID) Name() string {
 // range are represented by a dot (".").
 func (upid *SegmentationUPID) ASCIIValue() string {
 	b := upid.valueBytes()
-	rs := make([]byte, 0, len(b))
+	rs := make([]byte, len(b))
 	for i := range b {
 		if b[i] > 31 && b[i] < 127 {
 			rs[i] = b[i]

pkg/scte35/segmentation_upid_test.go

@@ -0,0 +1,29 @@
+package scte35_test
+
+import (
+	"testing"
+
+	"github.com/Comcast/scte35-go/pkg/scte35"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSegmentationUPID_ASCIIValue(t *testing.T) {
+	cases := map[string]struct {
+		upid     scte35.SegmentationUPID
+		expected string
+	}{
+		"Simple": {
+			upid: scte35.SegmentationUPID{
+				Type:  0x09,
+				Value: "SIGNAL:z1sFOMjCnV4AAAAAAAABAQ==",
+			},
+			expected: "SIGNAL:z1sFOMjCnV4AAAAAAAABAQ==",
+		},
+	}
+
+	for k, c := range cases {
+		t.Run(k, func(t *testing.T) {
+			require.Equal(t, c.expected, c.upid.ASCIIValue())
+		})
+	}
+}