Tests for Signature serialization (#11)

src/backend_libsecp256k1/libsecp256k1.nim

@@ -153,3 +153,8 @@ proc ecdsa_recover*(msg_hash: Hash[256], sig: Signature): PublicKey =
     raise newException(ValueError, "Failed to recover public key. Is the signature correct?")
 
 proc `$`*(key: PublicKey): string {.inline.} = key.toString()
+
+proc `$`*(s: Signature): string =
+  var data: array[65, byte]
+  s.serialize(data)
+  data.toHex()

tests/config.nim

@@ -36,6 +36,7 @@ type
     privkey*: string
     pubkey*: string
     raw_sig*: tuple[v: int, r, s: string]
+    serialized_sig*: string
 
 let
   MSG* = "message"
@@ -49,7 +50,8 @@ let
       v: 1,
       r: "80536744857756143861726945576089915884233437828013729338039544043241440681784",
       s: "1902566422691403459035240420865094128779958320521066670269403689808757640701"
-    )
+    ),
+    serialized_sig: "b20e2ea5d3cbaa83c1e0372f110cf12535648613b479b64c1a8c1a20c5021f380434d07ec5795e3f789794351658e80b7faf47a46328f41e019d7b853745cdfd01"
   )
 
   bob* = testKeySig(
@@ -59,8 +61,9 @@ let
       v: 1,
       r: "41741612198399299636429810387160790514780876799439767175315078161978521003886",
       s: "47545396818609319588074484786899049290652725314938191835667190243225814114102"
+      ),
+      serialized_sig: "5c48ea4f0f2257fa23bd25e6fcb0b75bbe2ff9bbda0167118dab2bb6e31ba76e691dbdaf2a231fc9958cd8edd99507121f8184042e075cf10f98ba88abff1f3601"
     )
-  )
 
   eve* = testKeySig(
     privkey: "876be0999ed9b7fc26f1b270903ef7b0c35291f89407903270fea611c85f515c",
@@ -69,5 +72,6 @@ let
       v: 0,
       r: "84467545608142925331782333363288012579669270632210954476013542647119929595395",
       s: "43529886636775750164425297556346136250671451061152161143648812009114516499167"
+      ),
+      serialized_sig: "babeefc5082d3ca2e0bc80532ab38f9cfb196fb9977401b2f6a98061f15ed603603d0af084bf906b2cdf6cdde8b2e1c3e51a41af5e9adec7f3643b3f1aa2aadf00"
     )
-  )

tests/test_key_and_signature_datastructures.nim

@@ -19,9 +19,10 @@ suite "Test key and signature data structure":
         pk = initPrivateKey(person.privkey)
         signature = pk.sign_msg(MSG)
 
-      check: signature.v == person.raw_sig.v
-      check: signature.r == person.raw_sig.r.u256
-      check: signature.s == person.raw_sig.s.u256
+      check:
+        signature.v == person.raw_sig.v
+        signature.r == person.raw_sig.r.u256
+        signature.s == person.raw_sig.s.u256
 
   test "Signing from private key object (ported from official eth-keys)":
     for person in [alice, bob, eve]:
@@ -32,15 +33,15 @@ suite "Test key and signature data structure":
       check: verify_msg(pk.public_key, MSG, signature)
 
   test "Hash signing from private key object":
-
     for person in [alice, bob, eve]:
       let
         pk = initPrivateKey(person.privkey)
         signature = pk.sign_msg(MSG)
 
-      check: signature.v == person.raw_sig.v
-      check: signature.r == person.raw_sig.r.u256
-      check: signature.s == person.raw_sig.s.u256
+      check:
+        signature.v == person.raw_sig.v
+        signature.r == person.raw_sig.r.u256
+        signature.s == person.raw_sig.s.u256
 
   test "Hash signing from private key object (ported from official eth-keys)":
     for person in [alice, bob, eve]:
@@ -69,3 +70,18 @@ suite "Test key and signature data structure":
         recovered_pubkey = recover_pubkey_from_msg(MSGHASH, signature)
 
       check: pk.public_key == recovered_pubkey
+
+  test "Signature serialization and deserialization":
+    for person in [alice, bob, eve]:
+      let
+        pk = initPrivateKey(person.privkey)
+        signature = pk.sign_msg(MSG)
+        deserializedSignature = parseSignature(hexToSeqByteBE(person.serialized_sig))
+
+      var serialized_sig: array[65, byte]
+      signature.serialize(serialized_sig)
+
+      check:
+        signature == deserializedSignature
+        serialized_sig.toHex() == person.serialized_sig
+        $signature == person.serialized_sig