Added a parsing/building round-trip test

src/ical/mod.rs

@@ -13,3 +13,44 @@ pub fn default_prod_id() -> String {
     format!("-//{}//{}//EN", ORG_NAME, PRODUCT_NAME)
 }
 
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use std::collections::HashSet;
+    use crate::item::SyncStatus;
+
+    #[test]
+    fn test_ical_round_trip_serde() {
+        let ical_with_unknown_fields = std::fs::read_to_string("tests/assets/ical_with_unknown_fields.ics").unwrap();
+
+        let item_id = "http://item.id".parse().unwrap();
+        let sync_status = SyncStatus::NotSynced;
+        let deserialized = parse(&ical_with_unknown_fields, item_id, sync_status).unwrap();
+        let serialized = build_from(&deserialized).unwrap();
+        assert_same_fields(&ical_with_unknown_fields, &serialized);
+    }
+
+    /// Assert the properties are present (possibly in another order)
+    /// RFC5545 "imposes no ordering of properties within an iCalendar object."
+    fn assert_same_fields(left: &str, right: &str) {
+        let left_parts: HashSet<&str> = left.split("\r\n").collect();
+        let right_parts: HashSet<&str> = right.split("\r\n").collect();
+
+        // Let's be more explicit than assert_eq!(left_parts, right_parts);
+        if left_parts != right_parts {
+            println!("Only in left:");
+            for item in left_parts.difference(&right_parts) {
+                println!("  * {}", item);
+            }
+            println!("Only in right:");
+            for item in right_parts.difference(&left_parts) {
+                println!("  * {}", item);
+            }
+
+            assert_eq!(left_parts, right_parts);
+        }
+    }
+}