feat: add custom StringSliceFlag type that allows escaping (#21)

drone/types.go

@@ -0,0 +1,40 @@
+package drone
+
+import (
+	"strings"
+)
+
+// StringSliceFlag is a flag type which support comma separated values and escaping to not split at unwanted lines
+type StringSliceFlag struct {
+	slice []string
+}
+
+func (s *StringSliceFlag) String() string {
+	return strings.Join(s.slice, " ")
+}
+
+func (s *StringSliceFlag) Set(value string) error {
+	s.slice = splitWithEscaping(value, ",", "\\")
+	return nil
+}
+
+func (s *StringSliceFlag) Get() []string {
+	return s.slice
+}
+
+func splitWithEscaping(s, separator, escapeString string) []string {
+	if len(s) == 0 {
+		return []string{}
+	}
+
+	a := strings.Split(s, separator)
+
+	for i := len(a) - 2; i >= 0; i-- {
+		if strings.HasSuffix(a[i], escapeString) {
+			a[i] = a[i][:len(a[i])-len(escapeString)] + separator + a[i+1]
+			a = append(a[:i+1], a[i+2:]...)
+		}
+	}
+
+	return a
+}

drone/types_test.go

@@ -0,0 +1,27 @@
+package drone
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestSplitWithEscaping(t *testing.T) {
+	tests := []struct {
+		Input  string
+		Output []string
+	}{
+		{"", []string{}},
+		{"a,b", []string{"a", "b"}},
+		{",,,", []string{"", "", "", ""}},
+		{",a\\,", []string{"", "a,"}},
+		{"a,b\\,c\\\\d,e", []string{"a", "b,c\\\\d", "e"}},
+	}
+
+	for _, test := range tests {
+		strings := splitWithEscaping(test.Input, ",", "\\")
+		got, want := strings, test.Output
+		if !reflect.DeepEqual(got, want) {
+			t.Errorf("Got tag %v, want %v", got, want)
+		}
+	}
+}