Add poseidon hash unit test (against ref values) (#299)

utils/tests/poseidon_hash.rs

@@ -0,0 +1,129 @@
+#[cfg(test)]
+mod test {
+    use ark_bn254::Fr;
+    use ark_ff::{AdditiveGroup, Field};
+    use std::collections::HashMap;
+    use std::str::FromStr;
+    use zerokit_utils::poseidon_hash::Poseidon;
+
+    const ROUND_PARAMS: [(usize, usize, usize, usize); 8] = [
+        (2, 8, 56, 0),
+        (3, 8, 57, 0),
+        (4, 8, 56, 0),
+        (5, 8, 60, 0),
+        (6, 8, 60, 0),
+        (7, 8, 63, 0),
+        (8, 8, 64, 0),
+        (9, 8, 63, 0),
+    ];
+
+    #[test]
+    fn test_poseidon_hash_basic() {
+        let map = HashMap::from([
+            (
+                Fr::ZERO,
+                Fr::from_str(
+                    "19014214495641488759237505126948346942972912379615652741039992445865937985820",
+                )
+                .unwrap(),
+            ),
+            (
+                Fr::ONE,
+                Fr::from_str(
+                    "18586133768512220936620570745912940619677854269274689475585506675881198879027",
+                )
+                .unwrap(),
+            ),
+            (
+                Fr::from(255),
+                Fr::from_str(
+                    "20026131459732984724454933360292530547665726761019872861025481903072111625788",
+                )
+                .unwrap(),
+            ),
+            (
+                Fr::from(u16::MAX),
+                Fr::from_str(
+                    "12358868638722666642632413418981275677998688723398440898957566982787708451243",
+                )
+                .unwrap(),
+            ),
+            (
+                Fr::from(u64::MAX),
+                Fr::from_str(
+                    "17449307747295017006142981453320720946812828330895590310359634430146721583189",
+                )
+                .unwrap(),
+            ),
+        ]);
+
+        for (k, v) in map.into_iter() {
+            let hasher = Poseidon::<Fr>::from(&ROUND_PARAMS);
+            let h = hasher.hash([k].to_vec());
+            assert_eq!(h.unwrap(), v);
+        }
+    }
+
+    #[test]
+    fn test_poseidon_hash_multi() {
+        // All hashes done in a merkle tree (with leaves: [0, 1, 2, 3, 4, 5? 6, 7])
+
+        // ~ leaves
+        let fr_0 = Fr::ZERO;
+        let fr_1 = Fr::ONE;
+        let fr_2 = Fr::from(2);
+        let fr_3 = Fr::from(3);
+        let fr_4 = Fr::from(4);
+        let fr_5 = Fr::from(5);
+        let fr_6 = Fr::from(6);
+        let fr_7 = Fr::from(7);
+
+        let fr_0_1 = Fr::from_str(
+            "12583541437132735734108669866114103169564651237895298778035846191048104863326",
+        )
+        .unwrap();
+        let fr_2_3 = Fr::from_str(
+            "17197790661637433027297685226742709599380837544520340689137581733613433332983",
+        )
+        .unwrap();
+        let fr_4_5 = Fr::from_str(
+            "756592041685769348226045093946546956867261766023639881791475046640232555043",
+        )
+        .unwrap();
+        let fr_6_7 = Fr::from_str(
+            "5558359459771725727593826278265342308584225092343962757289948761260561575479",
+        )
+        .unwrap();
+
+        let fr_0_3 = Fr::from_str(
+            "3720616653028013822312861221679392249031832781774563366107458835261883914924",
+        )
+        .unwrap();
+        let fr_4_7 = Fr::from_str(
+            "7960741062684589801276390367952372418815534638314682948141519164356522829957",
+        )
+        .unwrap();
+
+        // ~ root
+        let fr_0_7 = Fr::from_str(
+            "11780650233517635876913804110234352847867393797952240856403268682492028497284",
+        )
+        .unwrap();
+
+        let map = HashMap::from([
+            ((fr_0, fr_1), fr_0_1),
+            ((fr_2, fr_3), fr_2_3),
+            ((fr_4, fr_5), fr_4_5),
+            ((fr_6, fr_7), fr_6_7),
+            ((fr_0_1, fr_2_3), fr_0_3),
+            ((fr_4_5, fr_6_7), fr_4_7),
+            ((fr_0_3, fr_4_7), fr_0_7),
+        ]);
+
+        for (k, v) in map.into_iter() {
+            let hasher = Poseidon::<Fr>::from(&ROUND_PARAMS);
+            let h = hasher.hash([k.0, k.1].to_vec());
+            assert_eq!(h.unwrap(), v);
+        }
+    }
+}