make impl_runtime_api work without sp-api

bin/minimal/runtime/Cargo.toml

@@ -4,6 +4,10 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+parity-scale-codec = { version = "3.0.0", default-features = false }
+scale-info = { version = "2.6.0", default-features = false }
+
+# this is a frame-based runtime, thus importing `frame` with runtime feature enabled.
 frame = { path = "../../../frame", default-features = false, features = ["runtime"] }
 
 # pallets that we want to use
@@ -12,11 +16,6 @@ pallet-sudo = { path = "../../../frame/sudo", default-features = false }
 pallet-timestamp = { path = "../../../frame/timestamp", default-features = false }
 pallet-transaction-payment = { path = "../../../frame/transaction-payment", default-features = false }
 
-# TODO: https://github.com/paritytech/substrate/issues/14145
-sp-api = { path = "../../../primitives/api", default-features = false }
-
-parity-scale-codec = { version = "3.0.0", default-features = false }
-scale-info = { version = "2.6.0", default-features = false }
 
 [build-dependencies]
 substrate-wasm-builder = { path = "../../../utils/wasm-builder", optional = true }
@@ -31,8 +30,6 @@ std = [
 	"pallet-timestamp/std",
 	"pallet-transaction-payment/std",
 
-	"sp-api/std",
-
 	"parity-scale-codec/std",
 	"scale-info/std",
 

bin/minimal/runtime/src/lib.rs

@@ -13,10 +13,6 @@ use frame::{
 		weights::FixedFee,
 	},
 };
-
-// TODO: this is temp
-use frame::deps::frame_support;
-
 #[runtime_version]
 pub const VERSION: RuntimeVersion = RuntimeVersion {
 	spec_name: create_runtime_str!("minimal-runtime"),
@@ -89,6 +85,7 @@ impl pallet_balances::Config for Runtime {
 	type RuntimeHoldReason = RuntimeHoldReason;
 	type DustRemoval = ();
 	type AccountStore = System;
+	type ExistentialDeposit = ConstU128<1>;
 }
 
 #[derive_impl(pallet_sudo::config_preludes::SolochainDefaultConfig as pallet_sudo::DefaultConfig)]

frame/balances/src/lib.rs

@@ -222,7 +222,6 @@ pub mod pallet {
 		#[frame_support::register_default_impl(TestDefaultConfig)]
 		impl DefaultConfig for TestDefaultConfig {
 			type Balance = u64;
-			type ExistentialDeposit = ();
 			type MaxLocks = ConstU32<{ u32::MAX }>;
 			type MaxReserves = ConstU32<{ u32::MAX }>;
 			type MaxFreezes = ConstU32<{ u32::MAX }>;
@@ -238,7 +237,6 @@ pub mod pallet {
 		#[frame_support::register_default_impl(SolochainDefaultConfig)]
 		impl DefaultConfig for SolochainDefaultConfig {
 			type Balance = u128;
-			type ExistentialDeposit = ();
 			type MaxLocks = ConstU32<{ 128 }>;
 			type MaxReserves = ConstU32<{ 128 }>;
 			type MaxFreezes = ConstU32<{ 128 }>;
@@ -286,6 +284,7 @@ pub mod pallet {
 		///
 		/// Bottom line: Do yourself a favour and make it at least one!
 		#[pallet::constant]
+		#[pallet::no_default]
 		type ExistentialDeposit: Get<Self::Balance>;
 
 		/// The means of storing the balances of an account.

frame/examples/frame-api/src/lib.rs

@@ -1,5 +1,6 @@
 //! An example pallet built purely with the `frame` crate.
 
+#![cfg_attr(not(feature = "std"), no_std)]
 use frame::prelude::*;
 
 #[frame::pallet]
@@ -23,11 +24,6 @@ mod tests {
 	use super::pallet as pallet_example;
 	use frame::{prelude::*, testing_prelude::*};
 
-	// TODO: this is only for backwards compatibility with `tt_*` macros generated by other
-	// crates, which still force even a pallet/runtime made with `frame` need to have
-	// `frame_support` in scope.
-	use frame::deps::frame_support;
-
 	type UncheckedExtrinsic = MockUncheckedExtrinsic<Test>;
 	type Block = MockBlock<Test>;
 
@@ -45,9 +41,6 @@ mod tests {
 
 	#[derive_impl(frame_system::config_preludes::TestDefaultConfig as frame_system::DefaultConfig)]
 	impl frame_system::Config for Test {
-		// these items are defined by frame-system as `no_default`, so we must specify them here.
-		// Note that these are types that actually rely on the outer runtime, and can't sensibly
-		// have an _independent_ default.
 		type BaseCallFilter = frame::traits::Everything;
 		type RuntimeOrigin = RuntimeOrigin;
 		type RuntimeCall = RuntimeCall;

frame/src/lib.rs

@@ -66,16 +66,18 @@ pub mod prelude {
 	pub use sp_std::prelude::*;
 }
 
+pub use frame_support::log;
+
 #[cfg(feature = "std")]
 pub mod testing_prelude {
-	#[cfg(feature = "runtime")]
-	pub use super::runtime::testing_prelude::*;
+	pub use super::runtime::{prelude::*, testing_prelude::*};
 
 	pub use frame_support::{
 		assert_err, assert_err_ignore_postinfo, assert_error_encoded_size, assert_noop, assert_ok,
 		assert_storage_noop, derive_impl, ord_parameter_types, parameter_types,
 		parameter_types_impl_thread_local, storage_alias,
 	};
+
 	pub use frame_system::{self, mocking::*};
 	pub use sp_io::TestExternalities as TestState;
 }
@@ -117,12 +119,15 @@ pub mod derive {
 
 /// types that are often needed to amalgamate a real runtime. In principle, this is very similar to
 /// [`test`], but it contains production-ready types, as opposed to mocks.
-#[cfg(feature = "runtime")]
+#[cfg(any(feature = "runtime", feature = "std"))]
 pub mod runtime {
 	pub mod prelude {
 		pub use frame_executive::*;
 		pub use frame_support::{
-			construct_runtime, derive_impl, parameter_types,
+			self, // TODO: this is a temporary hack.
+			construct_runtime,
+			derive_impl,
+			parameter_types,
 			traits::{
 				ConstBool, ConstI128, ConstI16, ConstI32, ConstI64, ConstI8, ConstU128, ConstU16,
 				ConstU32, ConstU64, ConstU8,

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

@@ -51,6 +51,8 @@ pub fn generate_crate_access(unique_id: &str, def_crate: &str) -> TokenStream {
 /// for `frame-support` output will for example be `frame_support`.
 pub fn generate_crate_access_2018(def_crate: &str) -> Result<syn::Path, Error> {
 	if let Ok(FoundCrate::Name(name)) = crate_name(&"frame") {
+		// TODO: add tes to make sure `frame` always contains
+		// `frame::deps::frame_support/frame_system`.
 		let path = format!("{}::deps::{}", name, def_crate.to_string().replace("-", "_"));
 		let path = syn::parse_str::<syn::Path>(&path)?;
 		return Ok(path)
@@ -73,6 +75,9 @@ pub fn generate_hidden_includes(unique_id: &str, def_crate: &str) -> TokenStream
 	let mod_name = generate_hidden_includes_mod_name(unique_id);
 
 	if let Ok(FoundCrate::Name(name)) = crate_name(&"frame") {
+		// TODO: add tes to make sure `frame` always contains
+		// `frame::deps::frame_support/frame_system`.
+		// TODO: handle error.
 		let path = format!("{}::deps::{}", name, def_crate.to_string().replace("-", "_"));
 		let path = syn::parse_str::<syn::Path>(&path).unwrap();
 		return quote::quote!(

primitives/api/proc-macro/src/utils.rs

@@ -32,6 +32,14 @@ use inflector::Inflector;
 
 /// Generates the access to the `sc_client` crate.
 pub fn generate_crate_access() -> TokenStream {
+	if let Ok(FoundCrate::Name(name)) = crate_name(&"frame") {
+		// TODO: add tes to make sure `frame` always contains `frame::deps::sp_api`.
+		// TODO: handle error.
+		let path = format!("{}::deps::{}", name, "sp_api");
+		let path = syn::parse_str::<syn::Path>(&path).unwrap();
+		return path.into_token_stream()
+	}
+
 	match crate_name("sp-api") {
 		Ok(FoundCrate::Itself) => quote!(sp_api),
 		Ok(FoundCrate::Name(renamed_name)) => {