fork github.com/doug-martin

internal/tag/tags.go

@@ -0,0 +1,51 @@
+package tag
+
+import (
+	"reflect"
+	"strings"
+)
+
+// tagOptions is the string following a comma in a struct field's "json"
+// tag, or the empty string. It does not include the leading comma.
+type Options string
+
+func New(tagName string, st reflect.StructTag) Options {
+	return Options(st.Get(tagName))
+}
+
+func (o Options) Values() []string {
+	if string(o) == "" {
+		return []string{}
+	}
+	return strings.Split(string(o), ",")
+}
+
+// Contains reports whether a comma-separated list of options
+// contains a particular substr flag. substr must be surrounded by a
+// string boundary or commas.
+func (o Options) Contains(optionName string) bool {
+	if o.IsEmpty() {
+		return false
+	}
+	values := o.Values()
+	for _, s := range values {
+		if s == optionName {
+			return true
+		}
+	}
+	return false
+}
+
+// Contains reports whether a comma-separated list of options
+// contains a particular substr flag. substr must be surrounded by a
+// string boundary or commas.
+func (o Options) Equals(val string) bool {
+	if len(o) == 0 {
+		return false
+	}
+	return string(o) == val
+}
+
+func (o Options) IsEmpty() bool {
+	return len(o) == 0
+}