Use RuntimeString.

bin/node/runtime/src/lib.rs

@@ -31,7 +31,8 @@ pub use node_primitives::{AccountId, Signature};
 use node_primitives::{AccountIndex, Balance, BlockNumber, Hash, Index, Moment};
 use sp_api::impl_runtime_apis;
 use sp_runtime::{
-	Permill, Perbill, Percent, ApplyExtrinsicResult, impl_opaque_keys, generic, create_runtime_str,
+	Permill, Perbill, Percent, ApplyExtrinsicResult, RuntimeString,
+	impl_opaque_keys, generic, create_runtime_str,
 };
 use sp_runtime::curve::PiecewiseLinear;
 use sp_runtime::transaction_validity::TransactionValidity;
@@ -821,18 +822,17 @@ impl_runtime_apis! {
 			extrinsic: Vec<u8>,
 			steps: Vec<u32>,
 			repeat: u32,
-		) -> Result<Vec<frame_benchmarking::BenchmarkResults>, Vec<u8>> {
-			use codec::Encode;
+		) -> Result<Vec<frame_benchmarking::BenchmarkResults>, RuntimeString> {
 			use frame_benchmarking::Benchmarking;
 
-			let results = match module.as_slice() {
+			let result = match module.as_slice() {
 				b"pallet-balances" | b"balances" => Balances::run_benchmark(extrinsic, steps, repeat),
 				b"pallet-identity" | b"identity" => Identity::run_benchmark(extrinsic, steps, repeat),
 				b"pallet-timestamp" | b"timestamp" => Timestamp::run_benchmark(extrinsic, steps, repeat),
 				_ => Err("Benchmark not found for this pallet."),
 			};
 
-			results.map_err(|e| e.encode())
+			result.map_err(|e| e.into())
 		}
 	}
 }

frame/benchmarking/Cargo.toml

@@ -12,9 +12,10 @@ description = "Macro for benchmarking a FRAME runtime."
 codec = { package = "parity-scale-codec", version = "1.1.2", default-features = false }
 sp-api = { version = "2.0.0-alpha.2", path = "../../primitives/api", default-features = false }
 sp-runtime-interface = { version = "2.0.0-alpha.2", path = "../../primitives/runtime-interface", default-features = false }
+sp-runtime = { version = "2.0.0-alpha.2", path = "../../primitives/runtime", default-features = false }
 sp-std = { version = "2.0.0-alpha.2", path = "../../primitives/std", default-features = false }
 sp-io = { path = "../../primitives/io", default-features = false, version = "2.0.0-alpha.2" }
 
 [features]
 default = [ "std" ]
-std = [ "sp-runtime-interface/std", "sp-api/std", "codec/std", "sp-std/std" ]
+std = [ "sp-runtime-interface/std", "sp-runtime/std", "sp-api/std", "codec/std", "sp-std/std" ]

frame/benchmarking/src/utils.rs

@@ -19,6 +19,7 @@
 use codec::{Encode, Decode};
 use sp_std::vec::Vec;
 use sp_io::hashing::blake2_256;
+use sp_runtime::RuntimeString;
 
 /// An alphabet of possible parameters to use for benchmarking.
 #[derive(codec::Encode, codec::Decode, Clone, Copy, PartialEq, Debug)]
@@ -42,7 +43,7 @@ sp_api::decl_runtime_apis! {
 			extrinsic: Vec<u8>,
 			steps: Vec<u32>,
 			repeat: u32,
-		) -> Result<Vec<BenchmarkResults>, Vec<u8>>;
+		) -> Result<Vec<BenchmarkResults>, RuntimeString>;
 	}
 }
 

utils/frame/benchmarking-cli/src/lib.rs

@@ -110,7 +110,7 @@ impl BenchmarkCmd {
 		.execute(strategy.into())
 		.map_err(|e| format!("Error executing runtime benchmark: {:?}", e))?;
 
-		let results = <Result<Vec<BenchmarkResults>, Vec<u8>> as Decode>::decode(&mut &result[..])
+		let results = <Result<Vec<BenchmarkResults>, String> as Decode>::decode(&mut &result[..])
 			.expect("failed to decode benchmark results");
 
 		match results {
@@ -138,11 +138,7 @@ impl BenchmarkCmd {
 
 				eprintln!("Done.");
 			}
-			Err(error) => {
-				let error = <String as Decode>::decode(&mut &error[..])
-					.expect("failed to decode benchmark error");
-				eprintln!("Error: {:?}", error);
-			}
+			Err(error) => eprintln!("Error: {:?}", error),
 		}
 
 		Ok(())