GetCallIndex trait (#13558)

* GetCallIndex trait

* final impl

* ".git/.scripts/commands/fmt/fmt.sh"

* Docs

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* One more test

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* Doc

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: command-bot <>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

substrate/frame/support/procedural/src/lib.rs

@@ -984,7 +984,8 @@ pub fn compact(_: TokenStream, _: TokenStream) -> TokenStream {
 ///
 /// The macro creates an enum `Call` with one variant per dispatchable. This enum implements:
 /// [`Clone`], [`Eq`], [`PartialEq`], [`Debug`] (with stripped implementation in `not("std")`),
-/// `Encode`, `Decode`, `GetDispatchInfo`, `GetCallName`, and `UnfilteredDispatchable`.
+/// `Encode`, `Decode`, `GetDispatchInfo`, `GetCallName`, `GetCallIndex` and
+/// `UnfilteredDispatchable`.
 ///
 /// The macro implements the `Callable` trait on `Pallet` and a function `call_functions`
 /// which returns the dispatchable metadata.

substrate/frame/support/procedural/src/pallet/expand/call.rs

@@ -324,6 +324,21 @@ pub fn expand_call(def: &mut Def) -> proc_macro2::TokenStream {
 			}
 		}
 
+		impl<#type_impl_gen> #frame_support::dispatch::GetCallIndex for #call_ident<#type_use_gen>
+			#where_clause
+		{
+			fn get_call_index(&self) -> u8 {
+				match *self {
+					#( Self::#fn_name { .. } => #call_index, )*
+					Self::__Ignore(_, _) => unreachable!("__PhantomItem cannot be used."),
+				}
+			}
+
+			fn get_call_indices() -> &'static [u8] {
+				&[ #( #call_index, )* ]
+			}
+		}
+
 		impl<#type_impl_gen> #frame_support::traits::UnfilteredDispatchable
 			for #call_ident<#type_use_gen>
 			#where_clause