// Copyright 2015-2019 Parity Technologies (UK) Ltd.
// This file is part of Parity Ethereum.

// Parity Ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Parity Ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Parity Ethereum.  If not, see <http://www.gnu.org/licenses/>.

//! Nonoperative tracer.

use ethereum_types::{U256, Address};
use vm::{Error as VmError, ActionParams};
use crate::{
	Tracer, VMTracer, FlatTrace,
	trace::{VMTrace, RewardType}
};

/// Nonoperative tracer. Does not trace anything.
pub struct NoopTracer;

impl Tracer for NoopTracer {
	type Output = FlatTrace;

	fn prepare_trace_call(&mut self, _: &ActionParams, _: usize, _: bool) { }
	fn prepare_trace_create(&mut self, _: &ActionParams) { }
	fn done_trace_call(&mut self, _: U256, _: &[u8]) { }
	fn done_trace_create(&mut self, _: U256, _: &[u8], _: Address) { }
	fn done_trace_failed(&mut self, _: &VmError) { }
	fn trace_suicide(&mut self, _: Address, _: U256, _: Address) { }
	fn trace_reward(&mut self, _: Address, _: U256, _: RewardType) { }
	fn drain(self) -> Vec<FlatTrace> { vec![] }
}

/// Nonoperative VM tracer. Does not trace anything.
pub struct NoopVMTracer;

impl VMTracer for NoopVMTracer {
	type Output = VMTrace;

	fn drain(self) -> Option<VMTrace> { None }
}