Use frame-decode for core extrinsic decode logic (#1785)

* WIP using frame-decode for core extrinsic decode logic

* fmt

* Fix dependabot config

* clippy

* tidy some imports

* Fix a couple of tests

* Update to frame-decode 0.0.7

* fix docs

* Decode exts earlier to avoid doing it every iter/find step

* frame-decode to 0.1.0

* fmt

* clippy

* fix wasm example

* doc test fixes

* Fix test

* Fix a couple of subxt_core tests

subxt/src/blocks/block_types.rs

@@ -84,12 +84,12 @@ where
             return Err(BlockError::not_found(block_hash).into());
         };
 
-        Ok(Extrinsics::new(
+        Extrinsics::new(
             self.client.clone(),
             extrinsics,
             self.cached_events.clone(),
             block_hash,
-        )?)
+        )
     }
 
     /// Work with storage.

subxt/src/blocks/extrinsic_types.rs

@@ -6,7 +6,7 @@ use crate::{
     blocks::block_types::{get_events, CachedEvents},
     client::{OfflineClientT, OnlineClientT},
     config::{Config, Hasher},
-    error::{BlockError, Error},
+    error::Error,
     events,
 };
 
@@ -37,7 +37,7 @@ where
         extrinsics: Vec<Vec<u8>>,
         cached_events: CachedEvents<T>,
         hash: T::Hash,
-    ) -> Result<Self, BlockError> {
+    ) -> Result<Self, Error> {
         let inner = CoreExtrinsics::decode_from(extrinsics, client.metadata())?;
         Ok(Self {
             inner,
@@ -65,21 +65,13 @@ where
     /// Returns an iterator over the extrinsics in the block body.
     // Dev note: The returned iterator is 'static + Send so that we can box it up and make
     // use of it with our `FilterExtrinsic` stuff.
-    pub fn iter(
-        &self,
-    ) -> impl Iterator<Item = Result<ExtrinsicDetails<T, C>, Error>> + Send + Sync + 'static {
+    pub fn iter(&self) -> impl Iterator<Item = ExtrinsicDetails<T, C>> + Send + Sync + 'static {
         let client = self.client.clone();
         let cached_events = self.cached_events.clone();
         let block_hash = self.hash;
 
-        self.inner.iter().map(move |res| {
-            let inner = res?;
-            Ok(ExtrinsicDetails::new(
-                inner,
-                client.clone(),
-                block_hash,
-                cached_events.clone(),
-            ))
+        self.inner.iter().map(move |inner| {
+            ExtrinsicDetails::new(inner, client.clone(), block_hash, cached_events.clone())
         })
     }