fixup! Improve tests for the Update() function

nullable/nullable.go

@@ -0,0 +1,16 @@
+package nullable
+
+// Int ...
+func Int(i int) *int {
+	return &i
+}
+
+// Float64 ...
+func Float64(f float64) *float64 {
+	return &f
+}
+
+// String ...
+func String(s string) *string {
+	return &s
+}