Implement TypeInfo for Arc (#180)

* Implement `TypeInfo` for `Arc`

* Bump version to 2.7.0

* Update changelog

* Add link to the PR to the changelog

* Update UI test

CHANGELOG.md

@@ -5,6 +5,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.7.0] - 2023-05-15
+
+### Added
+- `TypeInfo` is now implemented for `Arc` [(#180)](https://github.com/paritytech/scale-info/pull/180)
+
 ## [2.6.0] - 2023-04-26
 
 ### Added

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "scale-info"
-version = "2.6.0"
+version = "2.7.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2021"
 rust-version = "1.60.0"

src/impls.rs

@@ -30,6 +30,7 @@ use crate::prelude::{
         RangeInclusive,
     },
     string::String,
+    sync::Arc,
     vec::Vec,
 };
 
@@ -279,6 +280,17 @@ where
     }
 }
 
+impl<T> TypeInfo for Arc<T>
+where
+    T: TypeInfo + ?Sized + 'static,
+{
+    type Identity = T;
+
+    fn type_info() -> Type {
+        Self::Identity::type_info()
+    }
+}
+
 impl<T> TypeInfo for &T
 where
     T: TypeInfo + ?Sized + 'static,

src/prelude.rs

@@ -37,6 +37,7 @@ cfg_if! {
             num,
             ops,
             string,
+            sync,
             vec,
         };
     } else {
@@ -46,6 +47,7 @@ cfg_if! {
             collections,
             format,
             string,
+            sync,
             vec,
         };
 

test_suite/tests/ui/fail_unions.stderr

@@ -23,7 +23,7 @@ error[E0277]: the trait bound `Commonwealth: TypeInfo` is not satisfied
              (A, B, C, D)
              (A, B, C, D, E)
              (A, B, C, D, E, F)
-           and 53 others
+           and $N others
 note: required by a bound in `assert_type_info`
   --> tests/ui/fail_unions.rs:11:24
    |