Use scale-encode and scale-decode to encode and decode based on metadata (#842)

* WIP EncodeAsType and DecodeAsType

* remove silly cli experiment code

* Get things finally compiling with EncodeAsType and DecodeAsType

* update codegen test and WrapperKeepOpaque proper impl (in case it shows up in codegen)

* fix tests

* accomodate scale-value changes

* starting to migrate to EncodeAsType/DecodeAsType

* static event decoding and tx encoding to use DecodeAsFields/EncodeAsFields

* some tidy up and add decode(skip) attrs where needed

* fix root event decoding

* #[codec(skip)] will do, and combine map_key stuff into storage_address since it's all specific to that

* fmt and clippy

* update Cargo.lock

* remove patched scale-encode

* bump scale-encode to 0.1 and remove unused dep in testing crate

* update deps and use released scale-decode

* update scale-value to latest to remove git branch

* Apply suggestions from code review

Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>

* remove sorting in derives/attr generation; spit them out in order given

* re-add derive sorting; it's a hashmap

* StaticTxPayload and DynamicTxPayload rolled into single Payload struct

* StaticStorageAddress and DynamicStorageAddress into single Address struct

* Fix storage address byte retrieval

* StaticConstantAddress and DynamicConstantAddress => Address

* Simplify storage codegen to fix test

* Add comments

* Alias to RuntimeEvent rather than making another, and prep for substituting call type

* remove unnecessary clone

* Fix docs and failing UI test

* root_bytes -> to_root_bytes

* document error case in StorageClient::address_bytes()

---------

Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>

subxt/src/utils/mod.rs

@@ -4,14 +4,14 @@
 
 //! Miscellaneous utility helpers.
 
-pub mod account_id;
+mod account_id;
 pub mod bits;
-pub mod multi_address;
-pub mod multi_signature;
+mod multi_address;
+mod multi_signature;
+mod wrapper_opaque;
 
 use codec::{
     Decode,
-    DecodeAll,
     Encode,
 };
 use derivative::Derivative;
@@ -19,6 +19,7 @@ use derivative::Derivative;
 pub use account_id::AccountId32;
 pub use multi_address::MultiAddress;
 pub use multi_signature::MultiSignature;
+pub use wrapper_opaque::WrapperKeepOpaque;
 
 // Used in codegen
 #[doc(hidden)]
@@ -39,51 +40,6 @@ impl codec::Encode for Encoded {
     }
 }
 
-/// A wrapper for any type `T` which implement encode/decode in a way compatible with `Vec<u8>`.
-///
-/// [`WrapperKeepOpaque`] stores the type only in its opaque format, aka as a `Vec<u8>`. To
-/// access the real type `T` [`Self::try_decode`] needs to be used.
-#[derive(Derivative, Encode, Decode)]
-#[derivative(
-    Debug(bound = ""),
-    Clone(bound = ""),
-    PartialEq(bound = ""),
-    Eq(bound = ""),
-    Default(bound = ""),
-    Hash(bound = "")
-)]
-pub struct WrapperKeepOpaque<T> {
-    data: Vec<u8>,
-    _phantom: PhantomDataSendSync<T>,
-}
-
-impl<T: Decode> WrapperKeepOpaque<T> {
-    /// Try to decode the wrapped type from the inner `data`.
-    ///
-    /// Returns `None` if the decoding failed.
-    pub fn try_decode(&self) -> Option<T> {
-        T::decode_all(&mut &self.data[..]).ok()
-    }
-
-    /// Returns the length of the encoded `T`.
-    pub fn encoded_len(&self) -> usize {
-        self.data.len()
-    }
-
-    /// Returns the encoded data.
-    pub fn encoded(&self) -> &[u8] {
-        &self.data
-    }
-
-    /// Create from the given encoded `data`.
-    pub fn from_encoded(data: Vec<u8>) -> Self {
-        Self {
-            data,
-            _phantom: PhantomDataSendSync::new(),
-        }
-    }
-}
-
 /// A version of [`std::marker::PhantomData`] that is also Send and Sync (which is fine
 /// because regardless of the generic param, it is always possible to Send + Sync this
 /// 0 size type).