Add invalid key testcases for XOnlyPublicKey::from_slice

Author: bigspider

src/schnorr.rs

@@ -320,6 +320,13 @@ mod tests {
     fn test_pubkey_from_slice() {
         assert_eq!(XOnlyPublicKey::from_slice(&[]), Err(InvalidPublicKey));
         assert_eq!(XOnlyPublicKey::from_slice(&[1, 2, 3]), Err(InvalidPublicKey));
+        assert_eq!(XOnlyPublicKey::from_slice(&crate::constants::ZERO), Err(InvalidPublicKey));
+        let invalid_pk = XOnlyPublicKey::from_slice(&[
+            0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+            0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+            0x11, 0x11, 0x11, 0x11, // no valid point has this x-coordinate
+        ]);
+        assert_eq!(invalid_pk, Err(InvalidPublicKey));
         let pk = XOnlyPublicKey::from_slice(&[
             0xB3, 0x3C, 0xC9, 0xED, 0xC0, 0x96, 0xD0, 0xA8, 0x34, 0x16, 0x96, 0x4B, 0xD3, 0xC6,
             0x24, 0x7B, 0x8F, 0xEC, 0xD2, 0x56, 0xE4, 0xEF, 0xA7, 0x87, 0x0D, 0x2C, 0x85, 0x4B,