spl: adding metadata account type

CHANGELOG.md

@@ -12,6 +12,7 @@ The minor version will be incremented upon a breaking change and the patch versi
 
 ### Features
 
+* spl: Add `MetadataAccount` account deserialization. ([#2014](https://github.com/coral-xyz/anchor/pull/2014)).
 * lang: Add `PartialEq` and `Eq` for `anchor_lang::Error` ([#1544](https://github.com/coral-xyz/anchor/pull/1544)).
 * cli: Add `--skip-build` to `anchor publish` ([#1786](https://github.
 com/project-serum/anchor/pull/1841)).

spl/src/metadata.rs

@@ -1,5 +1,6 @@
 use anchor_lang::context::CpiContext;
 use anchor_lang::{Accounts, Result, ToAccountInfos};
+use mpl_token_metadata::deser::meta_deser;
 use mpl_token_metadata::state::DataV2;
 use mpl_token_metadata::ID;
 use solana_program::account_info::AccountInfo;
@@ -183,3 +184,32 @@ pub struct MintNewEditionFromMasterEditionViaToken<'info> {
     //
     pub metadata_mint: AccountInfo<'info>,
 }
+
+#[derive(Clone, Debug, PartialEq)]
+pub struct MetadataAccount(mpl_token_metadata::state::Metadata);
+
+impl MetadataAccount {
+    pub const LEN: usize = mpl_token_metadata::state::MAX_METADATA_LEN;
+}
+
+impl anchor_lang::AccountDeserialize for MetadataAccount {
+    fn try_deserialize_unchecked(buf: &mut &[u8]) -> anchor_lang::Result<Self> {
+        let result = mpl_token_metadata::state::Metadata::deserialize(buf)?;
+        return Ok(MetadataAccount(result));
+    }
+}
+
+impl anchor_lang::AccountSerialize for MetadataAccount {}
+
+impl anchor_lang::Owner for MetadataAccount {
+    fn owner() -> Pubkey {
+        ID
+    }
+}
+
+impl Deref for MetadataAccount {
+    type Target = mpl_token_metadata::state::Metadata;
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}