Fix unwraps and other issues with benchmarks (#6957)

* Fix unwraps and other issues with benchmarks

* undo changes to contracts pallet

frame/benchmarking/src/lib.rs

@@ -660,7 +660,8 @@ macro_rules! benchmark_backend {
  // Prepare instance
  let $param = components.iter()
  .find(|&c| c.0 == $crate::BenchmarkParameter::$param)
- .unwrap().1;
+ .ok_or("Could not find component in benchmark preparation.")?
+ .1;
  )*
  $(
  let $pre_id : $pre_ty = $pre_ex;
@@ -778,6 +779,10 @@ macro_rules! impl_benchmark {
  $( stringify!($name) => SelectedBenchmark::$name, )*
  _ => return Err("Could not find extrinsic."),
  };
+ let mut results: Vec<$crate::BenchmarkResults> = Vec::new();
+ if repeat == 0 {
+ return Ok(results);
+ }
 
  // Add whitelist to DB including whitelisted caller
  let mut whitelist = whitelist.to_vec();
@@ -795,14 +800,13 @@ macro_rules! impl_benchmark {
  let components = <
  SelectedBenchmark as $crate::BenchmarkingSetup<T $(, $instance)?>
  >::components(&selected_benchmark);
- let mut results: Vec<$crate::BenchmarkResults> = Vec::new();
 
  // Default number of steps for a component.
  let mut prev_steps = 10;
 
  let repeat_benchmark = |
  repeat: u32,
- c: Vec<($crate::BenchmarkParameter, u32)>,
+ c: &[($crate::BenchmarkParameter, u32)],
  results: &mut Vec<$crate::BenchmarkResults>,
  verify: bool,
  | -> Result<(), &'static str> {
@@ -812,7 +816,7 @@ macro_rules! impl_benchmark {
  // benchmark.
  let closure_to_benchmark = <
  SelectedBenchmark as $crate::BenchmarkingSetup<T $(, $instance)?>
- >::instance(&selected_benchmark, &c, verify)?;
+ >::instance(&selected_benchmark, c, verify)?;
 
  // Set the block number to at least 1 so events are deposited.
  if $crate::Zero::is_zero(&frame_system::Module::<T>::block_number()) {
@@ -860,7 +864,7 @@ macro_rules! impl_benchmark {
  let elapsed_storage_root = finish_storage_root - start_storage_root;
 
  results.push($crate::BenchmarkResults {
- components: c.clone(),
+ components: c.to_vec(),
  extrinsic_time: elapsed_extrinsic,
  storage_root_time: elapsed_storage_root,
  reads: read_write_count.0,
@@ -920,9 +924,9 @@ macro_rules! impl_benchmark {
 
  if verify {
  // If `--verify` is used, run the benchmark once to verify it would complete.
- repeat_benchmark(1, Default::default(), &mut Vec::new(), true)?;
+ repeat_benchmark(1, &c, &mut Vec::new(), true)?;
  }
- repeat_benchmark(repeat, c, &mut results, false)?;
+ repeat_benchmark(repeat, &c, &mut results, false)?;
  }
  }
  }