add testable example

checkip_test.go

@@ -0,0 +1,48 @@
+package checkip
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net"
+)
+
+// WellKnown implements checkip.Info.
+type WellKnown bool
+
+func (wk WellKnown) Json() ([]byte, error) {
+	return json.Marshal(wk)
+}
+
+func (wk WellKnown) Summary() string {
+	return fmt.Sprintf("%v", wk)
+}
+
+// IsWellKnown implements checkip.Check.
+func IsWellKnown(ipaddr net.IP) (Result, error) {
+	res := Result{Name: "well known"}
+
+	wellKnown := []net.IP{
+		net.ParseIP("1.1.1.1"),
+		net.ParseIP("4.4.4.4"),
+		net.ParseIP("8.8.8.8"),
+	}
+
+	for _, wk := range wellKnown {
+		if string(ipaddr) == string(wk) {
+			res.Info = WellKnown(true)
+		}
+	}
+
+	return res, nil
+}
+
+func Example() {
+	ipaddr := net.ParseIP("1.1.1.1")
+	result, err := IsWellKnown(ipaddr)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println(result)
+	// Output: {well known Info false true}
+}