crypto: Spanify EllSwiftPubKey constructor

Author: sipa

src/pubkey.cpp

@@ -336,6 +336,12 @@ bool CPubKey::Derive(CPubKey& pubkeyChild, ChainCode &ccChild, unsigned int nChi
     return true;
 }
 
+EllSwiftPubKey::EllSwiftPubKey(Span<const std::byte> ellswift) noexcept
+{
+    assert(ellswift.size() == SIZE);
+    std::copy(ellswift.begin(), ellswift.end(), m_pubkey.begin());
+}
+
 CPubKey EllSwiftPubKey::Decode() const
 {
     secp256k1_pubkey pubkey;

src/pubkey.h

@@ -303,8 +303,7 @@ struct EllSwiftPubKey
     EllSwiftPubKey() noexcept = default;
 
     /** Construct a new ellswift public key from a given serialization. */
-    EllSwiftPubKey(const std::array<std::byte, SIZE>& ellswift) :
-        m_pubkey(ellswift) {}
+    EllSwiftPubKey(Span<const std::byte> ellswift) noexcept;
 
     /** Decode to normal compressed CPubKey (for debugging purposes). */
     CPubKey Decode() const;

src/test/bip324_tests.cpp

@@ -38,14 +38,8 @@ void TestBIP324PacketVector(
 {
     // Convert input from hex to char/byte vectors/arrays.
     const auto in_priv_ours = ParseHex(in_priv_ours_hex);
-    const auto in_ellswift_ours_vec = ParseHex<std::byte>(in_ellswift_ours_hex);
-    assert(in_ellswift_ours_vec.size() == 64);
-    std::array<std::byte, 64> in_ellswift_ours;
-    std::copy(in_ellswift_ours_vec.begin(), in_ellswift_ours_vec.end(), in_ellswift_ours.begin());
-    const auto in_ellswift_theirs_vec = ParseHex<std::byte>(in_ellswift_theirs_hex);
-    assert(in_ellswift_theirs_vec.size() == 64);
-    std::array<std::byte, 64> in_ellswift_theirs;
-    std::copy(in_ellswift_theirs_vec.begin(), in_ellswift_theirs_vec.end(), in_ellswift_theirs.begin());
+    const auto in_ellswift_ours = ParseHex<std::byte>(in_ellswift_ours_hex);
+    const auto in_ellswift_theirs = ParseHex<std::byte>(in_ellswift_theirs_hex);
     const auto in_contents = ParseHex<std::byte>(in_contents_hex);
     const auto in_aad = ParseHex<std::byte>(in_aad_hex);
     const auto mid_send_garbage = ParseHex<std::byte>(mid_send_garbage_hex);