Remove generation of instance trait by decl_storage. (#6812)

* remove generation of instance trait, no breaking change

* doc

* doc

* Update frame/support/src/traits.rs

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* Update frame/support/procedural/src/storage/instance_trait.rs

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
This commit is contained in:
Guillaume Thiolliere
2020-08-05 13:37:01 +02:00
committed by GitHub
parent e4e0e79ad7
commit 8a37f60844
7 changed files with 54 additions and 40 deletions
@@ -20,7 +20,7 @@
use proc_macro2::{TokenStream, Span};
use quote::quote;
use super::{DeclStorageDefExt, instance_trait::DEFAULT_INSTANTIABLE_TRAIT_NAME};
use super::DeclStorageDefExt;
use genesis_config_def::GenesisConfigDef;
use builder_def::BuilderDef;
@@ -104,10 +104,9 @@ fn impl_build_storage(
let name = syn::Ident::new(DEFAULT_INSTANCE_NAME, Span::call_site());
quote!( #name )
});
let inherent_instance_bound = def.optional_instance_bound.clone().unwrap_or_else(|| {
let bound = syn::Ident::new(DEFAULT_INSTANTIABLE_TRAIT_NAME, Span::call_site());
quote!( #inherent_instance: #bound )
});
let inherent_instance_bound = quote!(
#inherent_instance: #scrate::traits::Instance
);
let build_storage_impl = quote!(
<#runtime_generic: #runtime_trait, #inherent_instance_bound>
@@ -24,7 +24,6 @@ use super::DeclStorageDefExt;
const NUMBER_OF_INSTANCE: usize = 16;
pub(crate) const INHERENT_INSTANCE_NAME: &str = "__InherentHiddenInstance";
pub(crate) const DEFAULT_INSTANTIABLE_TRAIT_NAME: &str = "__GeneratedInstantiable";
// Used to generate an instance implementation.
struct InstanceDef {
@@ -36,7 +35,7 @@ struct InstanceDef {
pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStream {
let mut impls = TokenStream::new();
impls.extend(create_instance_trait(def));
impls.extend(reexport_instance_trait(scrate, def));
// Implementation of instances.
if let Some(module_instance) = &def.module_instance {
@@ -70,6 +69,8 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
.and_then(|i| i.instance_default.as_ref())
{
impls.extend(quote! {
/// Hidden instance generated to be internally used when module is used without
/// instance.
#[doc(hidden)]
pub type #inherent_instance = #default_instance;
});
@@ -77,7 +78,11 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
let instance_def = InstanceDef {
prefix: String::new(),
instance_struct: inherent_instance,
doc: quote!(#[doc(hidden)]),
doc: quote!(
/// Hidden instance generated to be internally used when module is used without
/// instance.
#[doc(hidden)]
),
};
impls.extend(create_and_impl_instance_struct(scrate, &instance_def, def));
}
@@ -85,27 +90,19 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
impls
}
fn create_instance_trait(
fn reexport_instance_trait(
scrate: &TokenStream,
def: &DeclStorageDefExt,
) -> TokenStream {
let instance_trait = def.module_instance.as_ref().map(|i| i.instance_trait.clone())
.unwrap_or_else(|| syn::Ident::new(DEFAULT_INSTANTIABLE_TRAIT_NAME, Span::call_site()));
let optional_hide = if def.module_instance.is_some() {
quote!()
if let Some(i) = def.module_instance.as_ref() {
let instance_trait = &i.instance_trait;
quote!(
/// Local import of frame_support::traits::Instance
// This import is not strictly needed but made in order not to have breaking change.
use #scrate::traits::Instance as #instance_trait;
)
} else {
quote!(#[doc(hidden)])
};
quote! {
/// Tag a type as an instance of a module.
///
/// Defines storage prefixes, they must be unique.
#optional_hide
pub trait #instance_trait: 'static {
/// The prefix used by any storage entry of an instance.
const PREFIX: &'static str;
}
quote!()
}
}
@@ -114,8 +111,7 @@ fn create_and_impl_instance_struct(
instance_def: &InstanceDef,
def: &DeclStorageDefExt,
) -> TokenStream {
let instance_trait = def.module_instance.as_ref().map(|i| i.instance_trait.clone())
.unwrap_or_else(|| syn::Ident::new(DEFAULT_INSTANTIABLE_TRAIT_NAME, Span::call_site()));
let instance_trait = quote!( #scrate::traits::Instance );
let instance_struct = &instance_def.instance_struct;
let prefix = format!("{}{}", instance_def.prefix, def.crate_name.to_string());
@@ -324,7 +324,16 @@ fn get_module_instance(
instantiable: Option<syn::Ident>,
default_instance: Option<syn::Ident>,
) -> syn::Result<Option<super::ModuleInstanceDef>> {
let right_syntax = "Should be $Instance: $Instantiable = $DefaultInstance";
let right_syntax = "Should be $I: $Instance = $DefaultInstance";
if instantiable.as_ref().map_or(false, |i| i != "Instance") {
let msg = format!(
"Instance trait must be named `Instance`, other names are no longer supported, because \
it is now defined at frame_support::traits::Instance. Expect `Instance` found `{}`",
instantiable.as_ref().unwrap(),
);
return Err(syn::Error::new(instantiable.span(), msg));
}
match (instance, instantiable, default_instance) {
(Some(instance), Some(instantiable), default_instance) => {
@@ -106,7 +106,7 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
type Query = #query_type;
fn module_prefix() -> &'static [u8] {
#instance_or_inherent::PREFIX.as_bytes()
<#instance_or_inherent as #scrate::traits::Instance>::PREFIX.as_bytes()
}
fn storage_prefix() -> &'static [u8] {
@@ -130,7 +130,7 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
for #storage_struct #optional_storage_where_clause
{
fn module_prefix() -> &'static [u8] {
#instance_or_inherent::PREFIX.as_bytes()
<#instance_or_inherent as #scrate::traits::Instance>::PREFIX.as_bytes()
}
fn storage_prefix() -> &'static [u8] {
@@ -145,7 +145,7 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
type Hasher = #scrate::#hasher;
fn module_prefix() -> &'static [u8] {
#instance_or_inherent::PREFIX.as_bytes()
<#instance_or_inherent as #scrate::traits::Instance>::PREFIX.as_bytes()
}
fn storage_prefix() -> &'static [u8] {
@@ -170,7 +170,7 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
for #storage_struct #optional_storage_where_clause
{
fn module_prefix() -> &'static [u8] {
#instance_or_inherent::PREFIX.as_bytes()
<#instance_or_inherent as #scrate::traits::Instance>::PREFIX.as_bytes()
}
fn storage_prefix() -> &'static [u8] {
@@ -188,7 +188,7 @@ pub fn decl_and_impl(scrate: &TokenStream, def: &DeclStorageDefExt) -> TokenStre
type Hasher2 = #scrate::#hasher2;
fn module_prefix() -> &'static [u8] {
#instance_or_inherent::PREFIX.as_bytes()
<#instance_or_inherent as #scrate::traits::Instance>::PREFIX.as_bytes()
}
fn storage_prefix() -> &'static [u8] {