Rename serialize_secret -> into_secret

The `serialize_secret` method is a conversion method. Rust naming
conventions for conversion methods that take a reference and returned an
owned type that implements `Copy` stipulate that the method should be
named `into_`.

Rename `serialize_secret` to be `into_secret`.

Author: tcharding

src/key.rs

@@ -212,9 +212,9 @@ impl SecretKey {
         SecretKey(sk)
     }
 
-    /// Serializes the secret key as byte value.
+    /// Gets the secret key as a byte value.
     #[inline]
-    pub fn serialize_secret(&self) -> [u8; constants::SECRET_KEY_SIZE] {
+    pub fn into_secret(&self) -> [u8; constants::SECRET_KEY_SIZE] {
         self.0
     }
 
@@ -809,9 +809,9 @@ impl KeyPair {
         KeyPair::new(SECP256K1, rng)
     }
 
-    /// Serializes the key pair as a secret key byte value.
+    /// Gets the secret bytes for this key pair.
     #[inline]
-    pub fn serialize_secret(&self) -> [u8; constants::SECRET_KEY_SIZE] {
+    pub fn into_secret(&self) -> [u8; constants::SECRET_KEY_SIZE] {
         *SecretKey::from_keypair(self).as_ref()
     }
 

src/secret.rs

@@ -35,7 +35,7 @@ macro_rules! impl_display_secret {
 
                 hasher.write(DEBUG_HASH_TAG);
                 hasher.write(DEBUG_HASH_TAG);
-                hasher.write(&self.serialize_secret());
+                hasher.write(&self.into_secret());
                 let hash = hasher.finish();
 
                 f.debug_tuple(stringify!($thing))
@@ -55,7 +55,7 @@ macro_rules! impl_display_secret {
                 let tag_hash = sha256::Hash::hash(tag.as_bytes());
                 engine.input(&tag_hash[..]);
                 engine.input(&tag_hash[..]);
-                engine.input(&self.serialize_secret());
+                engine.input(&self.into_secret());
                 let hash = sha256::Hash::from_engine(engine);
 
                 f.debug_tuple(stringify!($thing))
@@ -139,7 +139,7 @@ impl SecretKey {
     /// ```
     #[inline]
     pub fn display_secret(&self) -> DisplaySecret {
-        DisplaySecret { secret: self.serialize_secret() }
+        DisplaySecret { secret: self.into_secret() }
     }
 }
 
@@ -180,6 +180,6 @@ impl KeyPair {
     /// ```
     #[inline]
     pub fn display_secret(&self) -> DisplaySecret {
-        DisplaySecret { secret: self.serialize_secret() }
+        DisplaySecret { secret: self.into_secret() }
     }
 }