use cuckoofilter::{CuckooFilter, ExportedCuckooFilter}; use std::collections::hash_map::DefaultHasher; #[test] fn interoperability() { let total_items = 1_000_000; let mut filter = CuckooFilter::::with_capacity(total_items); let mut num_inserted: u64 = 0; // Fit as many values in as possible, count how many made it in. for i in 0..total_items { match filter.add(&i) { Ok(_) => num_inserted += 1, Err(_) => break, } } // Export the fingerprint data stored in the filter, // along with the filter's current length. let store: ExportedCuckooFilter = filter.export(); // Create a new filter using the `recover` method and the values previously exported. let recovered_filter = CuckooFilter::::from(store); // The range 0..num_inserted are all known to be in the filter. // The filters shouldn't return false negatives, and therefore they should all be contained. // Both filters should also be identical. for i in 0..num_inserted { assert!(filter.contains(&i)); assert!(recovered_filter.contains(&i)); } // The range total_items..(2 * total_items) are all known *not* to be in the filter. // Every element for which the filter claims that it is contained is therefore a false positive, and both the original filter and recovered filter should exhibit the same false positive behaviour. for i in total_items..(2 * total_items) { assert_eq!(filter.contains(&i), recovered_filter.contains(&i)); } } #[test] #[cfg(feature = "serde_support")] fn serialization() { // Just a small filter to test serialization. let mut filter = CuckooFilter::::with_capacity(100); // Fill a few values. for i in 0..50 { filter.add(&i).unwrap(); } // export data. let store: ExportedCuckooFilter = filter.export(); // serialize using json (for example, any serde format can be used). let saved_json = serde_json::to_string(&store).unwrap(); // create a new filter from the json string. let restore_json: ExportedCuckooFilter = serde_json::from_str(&saved_json).unwrap(); let recovered_filter = CuckooFilter::::from(restore_json); // Check our values exist within the reconstructed filter. for i in 0..50 { assert!(recovered_filter.contains(&i)); } }