github.com/divan/go-ethereum@v1.8.14-0.20180820134928-1de9ada4016d/eth/tracers/internal/tracers/opcount_tracer.js (about)

     1  // Copyright 2017 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  // opcountTracer is a sample tracer that just counts the number of instructions
    18  // executed by the EVM before the transaction terminated.
    19  {
    20  	// count tracks the number of EVM instructions executed.
    21  	count: 0,
    22  
    23  	// step is invoked for every opcode that the VM executes.
    24  	step: function(log, db) { this.count++ },
    25  
    26  	// fault is invoked when the actual execution of an opcode fails.
    27  	fault: function(log, db) { },
    28  
    29  	// result is invoked when all the opcodes have been iterated over and returns
    30  	// the final result of the tracing.
    31  	result: function(ctx, db) { return this.count }
    32  }