Add a common crate (#75)

* Add a barebones common crate

* Refactor some code into the common crate

* Add a `ResolverApi` interface.

This commit adds a `ResolverApi` trait to the `format` crate that can be
implemented by any type that can act as a resolver. A resolver is able
to provide information on the chain state. This chain state could be
fresh or it could be cached (which is something that we will do in a
future PR).

This cleans up our crate graph so that `format` is not depending on the
node interactions crate for the `EthereumNode` trait.

* Cleanup the blocking executor

crates/common/src/macros/define_wrapper_type.rs

@@ -0,0 +1,110 @@
+/// Defines wrappers around types.
+///
+/// For example, the macro invocation seen below:
+///
+/// ```rust,ignore
+/// define_wrapper_type!(CaseId => usize);
+/// ```
+///
+/// Would define a wrapper type that looks like the following:
+///
+/// ```rust,ignore
+/// pub struct CaseId(usize);
+/// ```
+///
+/// And would also implement a number of methods on this type making it easier to use.
+///
+/// These wrapper types become very useful as they make the code a lot easier to read.
+///
+/// Take the following as an example:
+///
+/// ```rust,ignore
+/// struct State {
+///     contracts: HashMap<usize, HashMap<String, Vec<u8>>>
+/// }
+/// ```
+///
+/// In the above code it's hard to understand what the various types refer to or what to expect them
+/// to contain.
+///
+/// With these wrapper types we're able to create code that's self-documenting in that the types
+/// tell us what the code is referring to. The above code is transformed into
+///
+/// ```rust,ignore
+/// struct State {
+///     contracts: HashMap<CaseId, HashMap<ContractName, ContractByteCode>>
+/// }
+/// ```
+///
+/// Note that we follow the same syntax for defining wrapper structs but we do not permit the use of
+/// generics.
+#[macro_export]
+macro_rules! define_wrapper_type {
+    (
+        $(#[$meta: meta])*
+        $vis:vis struct $ident: ident($ty: ty);
+    ) => {
+        $(#[$meta])*
+        $vis struct $ident($ty);
+
+        impl $ident {
+            pub fn new(value: $ty) -> Self {
+                Self(value)
+            }
+
+            pub fn new_from<T: Into<$ty>>(value: T) -> Self {
+                Self(value.into())
+            }
+
+            pub fn into_inner(self) -> $ty {
+                self.0
+            }
+
+            pub fn as_inner(&self) -> &$ty {
+                &self.0
+            }
+        }
+
+        impl AsRef<$ty> for $ident {
+            fn as_ref(&self) -> &$ty {
+                &self.0
+            }
+        }
+
+        impl AsMut<$ty> for $ident {
+            fn as_mut(&mut self) -> &mut $ty {
+                &mut self.0
+            }
+        }
+
+        impl std::ops::Deref for $ident {
+            type Target = $ty;
+
+            fn deref(&self) -> &Self::Target {
+                &self.0
+            }
+        }
+
+        impl std::ops::DerefMut for $ident {
+            fn deref_mut(&mut self) -> &mut Self::Target {
+                &mut self.0
+            }
+        }
+
+        impl From<$ty> for $ident {
+            fn from(value: $ty) -> Self {
+                Self(value)
+            }
+        }
+
+        impl From<$ident> for $ty {
+            fn from(value: $ident) -> Self {
+                value.0
+            }
+        }
+    };
+}
+
+/// Technically not needed but this allows for the macro to be found in the `macros` module of the
+/// crate in addition to being found in the root of the crate.
+pub use define_wrapper_type;

crates/common/src/macros/mod.rs

@@ -0,0 +1,3 @@
+mod define_wrapper_type;
+
+pub use define_wrapper_type::*;