test-runtime: GenesisBuilder runtime API impl + tests (#14310)

* test-runtime: GenesisBuilder runtime API impl + tests

This PR provides implementation of `GenesisBuilder` API for `substrate-test-runtime`, can be considered as reference imiplementation for other runtimes.
The `GenesisBuilder` implementation is gated by `gensis-config` feature.

Tested scenarios:
- default `GenesisConfig` to JSON blob,
- deserialization of `GenesisConfig` from custom JSON, and storing its keys into the Storage (genesis storage creation).
- creation of genesis storage using partial JSON definition,
- checking if invalid/renamed JSON files causes the runtime to panic,

* missing file added

* client: GenesisBuilder helper added

* feature renamed: genesis-config -> genesis-builder

* Update Cargo.toml

* Update Cargo.toml

* Update Cargo.toml

* Update Cargo.toml

* redundant function removed

* genesis builder helper: introduced RuntimeGenesisBuild

* test-runtime: get rid of unused T

* redundant bound removed

* helper: use GenesisBuild again

* tests adjusted for on_genesis

* test-runtime: support for BuildGenesisConfig

* helper: BuildGenesisConfig support

* Update client/genesis-builder/src/lib.rs

Co-authored-by: Davide Galassi <davxy@datawok.net>

* Update test-utils/runtime/src/test_json/readme.md

Co-authored-by: Davide Galassi <davxy@datawok.net>

* Update test-utils/runtime/src/test_json/readme.md

Co-authored-by: Davide Galassi <davxy@datawok.net>

* Update test-utils/runtime/src/genesismap.rs

Co-authored-by: Davide Galassi <davxy@datawok.net>

* jsons are now human-friendly

* fix

* improvements

* jsons fixed

* helper: no_defaults added

* test-runtime: no_defaults added

* test-runtime: patching fn removed

* helper: patching fn removed

* helper: moved to frame_support

* test-runtime: fixes

* Cargo.lock updated

* fmt + naming

* test-runtime: WasmExecutor used

* helper / test-runtime: struct removed

* test-runtime: merge fixes

* Cargo.lock + test-utils/runtime/Cargo.toml updated

* doc fixed

* client/rpc: test fixed (new rt api)

* client/rpc-spec-v2: test fix

* doc fix

* test-runtime: disable-genesis-builder feature

* fix

* fix

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

* test-runtime: rerun added to build script

---------

Co-authored-by: Davide Galassi <davxy@datawok.net>
Co-authored-by: parity-processbot <>

substrate/frame/support/src/genesis_builder_helper.rs

@@ -0,0 +1,41 @@
+// This file is part of Substrate.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Helper functions for implementing [`sp_genesis_builder::GenesisBuilder`] for runtimes.
+//!
+//! Provides common logic. For more info refer to [`sp_genesis_builder::GenesisBuilder`].
+
+use frame_support::traits::BuildGenesisConfig;
+use sp_genesis_builder::Result as BuildResult;
+use sp_runtime::format_runtime_string;
+
+/// Get the default `GenesisConfig` as a JSON blob. For more info refer to
+/// [`sp_genesis_builder::GenesisBuilder::create_default_config`]
+pub fn create_default_config<GC: BuildGenesisConfig>() -> sp_std::vec::Vec<u8> {
+	serde_json::to_string(&GC::default())
+		.expect("serialization to json is expected to work. qed.")
+		.into_bytes()
+}
+
+/// Build `GenesisConfig` from a JSON blob not using any defaults and store it in the storage. For
+/// more info refer to [`sp_genesis_builder::GenesisBuilder::build_config`].
+pub fn build_config<GC: BuildGenesisConfig>(json: sp_std::vec::Vec<u8>) -> BuildResult {
+	let gc = serde_json::from_slice::<GC>(&json)
+		.map_err(|e| format_runtime_string!("Invalid JSON blob: {}", e))?;
+	<GC as BuildGenesisConfig>::build(&gc);
+	Ok(())
+}

substrate/frame/support/src/lib.rs

@@ -2915,3 +2915,6 @@ pub use frame_support_procedural::register_default_impl;
 
 // Generate a macro that will enable/disable code based on `std` feature being active.
 sp_core::generate_feature_enabled_macro!(std_enabled, feature = "std", $);
+
+// Helper for implementing GenesisBuilder runtime API
+pub mod genesis_builder_helper;