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cmd, core, eth/tracers: support fancier js tracing (#15516)

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* cmd, core, eth/tracers: support fancier js tracing

* eth, internal/web3ext: rework trace API, concurrency, chain tracing

* eth/tracers: add three more JavaScript tracers

* eth/tracers, vendor: swap ottovm to duktape for tracing

* core, eth, internal: finalize call tracer and needed extras

* eth, tests: prestate tracer, call test suite, rewinding

* vendor: fix windows builds for tracer js engine

* vendor: temporary duktape fix

* eth/tracers: fix up 4byte and evmdis tracer

* vendor: pull in latest duktape with my upstream fixes

* eth: fix some review comments

* eth: rename rewind to reexec to make it more obvious

* core/vm: terminate tracing using defers
This commit is contained in:
Péter Szilágyi
2017-12-21 13:56:11 +02:00
committed by GitHub
parent 1a5425779b
commit 5258785c81
64 changed files with 109115 additions and 685 deletions
Download Patch File Download Diff File Expand all files Collapse all files

86
eth/tracers/internal/tracers/4byte_tracer.js Normal file
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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// 4byteTracer searches for 4byte-identifiers, and collects them for post-processing.
// It collects the methods identifiers along with the size of the supplied data, so
// a reversed signature can be matched against the size of the data.
//
// Example:
// > debug.traceTransaction( "0x214e597e35da083692f5386141e69f47e973b2c56e7a8073b1ea08fd7571e9de", {tracer: "4byteTracer"})
// {
// 0x27dc297e-128: 1,
// 0x38cc4831-0: 2,
// 0x524f3889-96: 1,
// 0xadf59f99-288: 1,
// 0xc281d19e-0: 1
// }
{
// ids aggregates the 4byte ids found.
ids : {},
// callType returns 'false' for non-calls, or the peek-index for the first param
// after 'value', i.e. meminstart.
callType: function(opstr){
switch(opstr){
case "CALL": case "CALLCODE":
// gas, addr, val, memin, meminsz, memout, memoutsz
return 3; // stack ptr to memin
case "DELEGATECALL": case "STATICCALL":
// gas, addr, memin, meminsz, memout, memoutsz
return 2; // stack ptr to memin
}
return false;
},
// store save the given indentifier and datasize.
store: function(id, size){
var key = "" + toHex(id) + "-" + size;
this.ids[key] = this.ids[key] + 1 || 1;
},
// step is invoked for every opcode that the VM executes.
step: function(log, db) {
// Skip any opcodes that are not internal calls
var ct = this.callType(log.op.toString());
if (!ct) {
return;
}
// Skip any pre-compile invocations, those are just fancy opcodes
if (isPrecompiled(toAddress(log.stack.peek(1)))) {
return;
}
// Gather internal call details
var inSz = log.stack.peek(ct + 1).valueOf();
if (inSz >= 4) {
var inOff = log.stack.peek(ct).valueOf();
this.store(log.memory.slice(inOff, inOff + 4), inSz-4);
}
},
// fault is invoked when the actual execution of an opcode fails.
fault: function(log, db) { },
// result is invoked when all the opcodes have been iterated over and returns
// the final result of the tracing.
result: function(ctx) {
// Save the outer calldata also
if (ctx.input.length > 4) {
this.store(slice(ctx.input, 0, 4), ctx.input.length-4)
}
return this.ids;
},
}

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eth/tracers/internal/tracers/call_tracer.js Normal file
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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// callTracer is a full blown transaction tracer that extracts and reports all
// the internal calls made by a transaction, along with any useful information.
{
// callstack is the current recursive call stack of the EVM execution.
callstack: [{}],
// descended tracks whether we've just descended from an outer transaction into
// an inner call.
descended: false,
// step is invoked for every opcode that the VM executes.
step: function(log, db) {
// Capture any errors immediately
var error = log.getError();
if (error !== undefined) {
this.fault(log, db);
return;
}
// We only care about system opcodes, faster if we pre-check once
var syscall = (log.op.toNumber() & 0xf0) == 0xf0;
if (syscall) {
var op = log.op.toString();
}
// If a new contract is being created, add to the call stack
if (syscall && op == 'CREATE') {
var inOff = log.stack.peek(1).valueOf();
var inEnd = inOff + log.stack.peek(2).valueOf();
// Assemble the internal call report and store for completion
var call = {
type: op,
from: toHex(log.contract.getAddress()),
input: toHex(log.memory.slice(inOff, inEnd)),
gasIn: log.getGas(),
gasCost: log.getCost(),
value: '0x' + log.stack.peek(0).toString(16)
};
this.callstack.push(call);
this.descended = true
return;
}
// If a contract is being self destructed, gather that as a subcall too
if (syscall && op == 'SELFDESTRUCT') {
var left = this.callstack.length;
if (this.callstack[left-1].calls === undefined) {
this.callstack[left-1].calls = [];
}
this.callstack[left-1].calls.push({type: op});
return
}
// If a new method invocation is being done, add to the call stack
if (syscall && (op == 'CALL' || op == 'CALLCODE' || op == 'DELEGATECALL' || op == 'STATICCALL')) {
// Skip any pre-compile invocations, those are just fancy opcodes
var to = toAddress(log.stack.peek(1).toString(16));
if (isPrecompiled(to)) {
return
}
var off = (op == 'DELEGATECALL' || op == 'STATICCALL' ? 0 : 1);
var inOff = log.stack.peek(2 + off).valueOf();
var inEnd = inOff + log.stack.peek(3 + off).valueOf();
// Assemble the internal call report and store for completion
var call = {
type: op,
from: toHex(log.contract.getAddress()),
to: toHex(to),
input: toHex(log.memory.slice(inOff, inEnd)),
gasIn: log.getGas(),
gasCost: log.getCost(),
outOff: log.stack.peek(4 + off).valueOf(),
outLen: log.stack.peek(5 + off).valueOf()
};
if (op != 'DELEGATECALL' && op != 'STATICCALL') {
call.value = '0x' + log.stack.peek(2).toString(16);
}
this.callstack.push(call);
this.descended = true
return;
}
// If we've just descended into an inner call, retrieve it's true allowance. We
// need to extract if from within the call as there may be funky gas dynamics
// with regard to requested and actually given gas (2300 stipend, 63/64 rule).
if (this.descended) {
if (log.getDepth() >= this.callstack.length) {
this.callstack[this.callstack.length - 1].gas = log.getGas();
} else {
// TODO(karalabe): The call was made to a plain account. We currently don't
// have access to the true gas amount inside the call and so any amount will
// mostly be wrong since it depends on a lot of input args. Skip gas for now.
}
this.descended = false;
}
// If an existing call is returning, pop off the call stack
if (syscall && op == 'REVERT') {
this.callstack[this.callstack.length - 1].error = "execution reverted";
return;
}
if (log.getDepth() == this.callstack.length - 1) {
// Pop off the last call and get the execution results
var call = this.callstack.pop();
if (call.type == 'CREATE') {
// If the call was a CREATE, retrieve the contract address and output code
call.gasUsed = '0x' + bigInt(call.gasIn - call.gasCost - log.getGas()).toString(16);
delete call.gasIn; delete call.gasCost;
var ret = log.stack.peek(0);
if (!ret.equals(0)) {
call.to = toHex(toAddress(ret.toString(16)));
call.output = toHex(db.getCode(toAddress(ret.toString(16))));
} else if (call.error === undefined) {
call.error = "internal failure"; // TODO(karalabe): surface these faults somehow
}
} else {
// If the call was a contract call, retrieve the gas usage and output
if (call.gas !== undefined) {
call.gasUsed = '0x' + bigInt(call.gasIn - call.gasCost + call.gas - log.getGas()).toString(16);
var ret = log.stack.peek(0);
if (!ret.equals(0)) {
call.output = toHex(log.memory.slice(call.outOff, call.outOff + call.outLen));
} else if (call.error === undefined) {
call.error = "internal failure"; // TODO(karalabe): surface these faults somehow
}
}
delete call.gasIn; delete call.gasCost;
delete call.outOff; delete call.outLen;
}
if (call.gas !== undefined) {
call.gas = '0x' + bigInt(call.gas).toString(16);
}
// Inject the call into the previous one
var left = this.callstack.length;
if (this.callstack[left-1].calls === undefined) {
this.callstack[left-1].calls = [];
}
this.callstack[left-1].calls.push(call);
}
},
// fault is invoked when the actual execution of an opcode fails.
fault: function(log, db) {
// If the topmost call already reverted, don't handle the additional fault again
if (this.callstack[this.callstack.length - 1].error !== undefined) {
return;
}
// Pop off the just failed call
var call = this.callstack.pop();
call.error = log.getError();
// Consume all available gas and clean any leftovers
if (call.gas !== undefined) {
call.gas = '0x' + bigInt(call.gas).toString(16);
call.gasUsed = call.gas
}
delete call.gasIn; delete call.gasCost;
delete call.outOff; delete call.outLen;
// Flatten the failed call into its parent
var left = this.callstack.length;
if (left > 0) {
if (this.callstack[left-1].calls === undefined) {
this.callstack[left-1].calls = [];
}
this.callstack[left-1].calls.push(call);
return;
}
// Last call failed too, leave it in the stack
this.callstack.push(call);
},
// result is invoked when all the opcodes have been iterated over and returns
// the final result of the tracing.
result: function(ctx, db) {
var result = {
type: ctx.type,
from: toHex(ctx.from),
to: toHex(ctx.to),
value: '0x' + ctx.value.toString(16),
gas: '0x' + bigInt(ctx.gas).toString(16),
gasUsed: '0x' + bigInt(ctx.gasUsed).toString(16),
input: toHex(ctx.input),
output: toHex(ctx.output),
time: ctx.time,
};
if (this.callstack[0].calls !== undefined) {
result.calls = this.callstack[0].calls;
}
if (this.callstack[0].error !== undefined) {
result.error = this.callstack[0].error;
} else if (ctx.error !== undefined) {
result.error = ctx.error;
}
if (result.error !== undefined) {
delete result.output;
}
return this.finalize(result);
},
// finalize recreates a call object using the final desired field oder for json
// serialization. This is a nicety feature to pass meaningfully ordered results
// to users who don't interpret it, just display it.
finalize: function(call) {
var sorted = {
type: call.type,
from: call.from,
to: call.to,
value: call.value,
gas: call.gas,
gasUsed: call.gasUsed,
input: call.input,
output: call.output,
error: call.error,
time: call.time,
calls: call.calls,
}
for (var key in sorted) {
if (sorted[key] === undefined) {
delete sorted[key];
}
}
if (sorted.calls !== undefined) {
for (var i=0; i<sorted.calls.length; i++) {
sorted.calls[i] = this.finalize(sorted.calls[i]);
}
}
return sorted;
}
}

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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// evmdisTracer returns sufficent information from a trace to perform evmdis-style
// disassembly.
{
stack: [{ops: []}],
npushes: {0: 0, 1: 1, 2: 1, 3: 1, 4: 1, 5: 1, 6: 1, 7: 1, 8: 1, 9: 1, 10: 1, 11: 1, 16: 1, 17: 1, 18: 1, 19: 1, 20: 1, 21: 1, 22: 1, 23: 1, 24: 1, 25: 1, 26: 1, 32: 1, 48: 1, 49: 1, 50: 1, 51: 1, 52: 1, 53: 1, 54: 1, 55: 0, 56: 1, 57: 0, 58: 1, 59: 1, 60: 0, 64: 1, 65: 1, 66: 1, 67: 1, 68: 1, 69: 1, 80: 0, 81: 1, 82: 0, 83: 0, 84: 1, 85: 0, 86: 0, 87: 0, 88: 1, 89: 1, 90: 1, 91: 0, 96: 1, 97: 1, 98: 1, 99: 1, 100: 1, 101: 1, 102: 1, 103: 1, 104: 1, 105: 1, 106: 1, 107: 1, 108: 1, 109: 1, 110: 1, 111: 1, 112: 1, 113: 1, 114: 1, 115: 1, 116: 1, 117: 1, 118: 1, 119: 1, 120: 1, 121: 1, 122: 1, 123: 1, 124: 1, 125: 1, 126: 1, 127: 1, 128: 2, 129: 3, 130: 4, 131: 5, 132: 6, 133: 7, 134: 8, 135: 9, 136: 10, 137: 11, 138: 12, 139: 13, 140: 14, 141: 15, 142: 16, 143: 17, 144: 2, 145: 3, 146: 4, 147: 5, 148: 6, 149: 7, 150: 8, 151: 9, 152: 10, 153: 11, 154: 12, 155: 13, 156: 14, 157: 15, 158: 16, 159: 17, 160: 0, 161: 0, 162: 0, 163: 0, 164: 0, 240: 1, 241: 1, 242: 1, 243: 0, 244: 0, 255: 0},
// result is invoked when all the opcodes have been iterated over and returns
// the final result of the tracing.
result: function() { return this.stack[0].ops; },
// fault is invoked when the actual execution of an opcode fails.
fault: function(log, db) { },
// step is invoked for every opcode that the VM executes.
step: function(log, db) {
var frame = this.stack[this.stack.length - 1];
var error = log.getError();
if (error) {
frame["error"] = error;
} else if (log.getDepth() == this.stack.length) {
opinfo = {
op: log.op.toNumber(),
depth : log.getDepth(),
result: [],
};
if (frame.ops.length > 0) {
var prevop = frame.ops[frame.ops.length - 1];
for(var i = 0; i < this.npushes[prevop.op]; i++)
prevop.result.push(log.stack.peek(i).toString(16));
}
switch(log.op.toString()) {
case "CALL": case "CALLCODE":
var instart = log.stack.peek(3).valueOf();
var insize = log.stack.peek(4).valueOf();
opinfo["gas"] = log.stack.peek(0).valueOf();
opinfo["to"] = log.stack.peek(1).toString(16);
opinfo["value"] = log.stack.peek(2).toString();
opinfo["input"] = log.memory.slice(instart, instart + insize);
opinfo["error"] = null;
opinfo["return"] = null;
opinfo["ops"] = [];
this.stack.push(opinfo);
break;
case "DELEGATECALL": case "STATICCALL":
var instart = log.stack.peek(2).valueOf();
var insize = log.stack.peek(3).valueOf();
opinfo["op"] = log.op.toString();
opinfo["gas"] = log.stack.peek(0).valueOf();
opinfo["to"] = log.stack.peek(1).toString(16);
opinfo["input"] = log.memory.slice(instart, instart + insize);
opinfo["error"] = null;
opinfo["return"] = null;
opinfo["ops"] = [];
this.stack.push(opinfo);
break;
case "RETURN":
var out = log.stack.peek(0).valueOf();
var outsize = log.stack.peek(1).valueOf();
frame.return = log.memory.slice(out, out + outsize);
break;
case "STOP": case "SUICIDE":
frame.return = log.memory.slice(0, 0);
break;
case "JUMPDEST":
opinfo["pc"] = log.getPC();
}
if(log.op.isPush()) {
opinfo["len"] = log.op.toNumber() - 0x5e;
}
frame.ops.push(opinfo);
} else {
this.stack = this.stack.slice(0, log.getDepth());
}
}
}

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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// noopTracer is just the barebone boilerplate code required from a JavaScript
// object to be usable as a transaction tracer.
{
// step is invoked for every opcode that the VM executes.
step: function(log, db) { },
// fault is invoked when the actual execution of an opcode fails.
fault: function(log, db) { },
// result is invoked when all the opcodes have been iterated over and returns
// the final result of the tracing.
result: function(ctx, db) { }
}

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eth/tracers/internal/tracers/opcount_tracer.js Normal file
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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// opcountTracer is a sample tracer that just counts the number of instructions
// executed by the EVM before the transaction terminated.
{
// count tracks the number of EVM instructions executed.
count: 0,
// step is invoked for every opcode that the VM executes.
step: function(log, db) { this.count++ },
// fault is invoked when the actual execution of an opcode fails.
fault: function(log, db) { },
// result is invoked when all the opcodes have been iterated over and returns
// the final result of the tracing.
result: function(ctx, db) { return this.count }
}

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eth/tracers/internal/tracers/prestate_tracer.js Normal file
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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// prestateTracer outputs sufficient information to create a local execution of
// the transaction from a custom assembled genesis block.
{
// prestate is the genesis that we're building.
prestate: null,
// lookupAccount injects the specified account into the prestate object.
lookupAccount: function(addr, db){
var acc = toHex(addr);
if (this.prestate[acc] === undefined) {
this.prestate[acc] = {
balance: '0x' + db.getBalance(addr).toString(16),
nonce: db.getNonce(addr),
code: toHex(db.getCode(addr)),
storage: {}
};
}
},
// lookupStorage injects the specified storage entry of the given account into
// the prestate object.
lookupStorage: function(addr, key, db){
var acc = toHex(addr);
var idx = toHex(key);
if (this.prestate[acc].storage[idx] === undefined) {
var val = toHex(db.getState(addr, key));
if (val != "0x0000000000000000000000000000000000000000000000000000000000000000") {
this.prestate[acc].storage[idx] = toHex(db.getState(addr, key));
}
}
},
// result is invoked when all the opcodes have been iterated over and returns
// the final result of the tracing.
result: function(ctx, db) {
// At this point, we need to deduct the 'value' from the
// outer transaction, and move it back to the origin
this.lookupAccount(ctx.from, db);
var fromBal = bigInt(this.prestate[toHex(ctx.from)].balance.slice(2), 16);
var toBal = bigInt(this.prestate[toHex(ctx.to)].balance.slice(2), 16);
this.prestate[toHex(ctx.to)].balance = '0x'+toBal.subtract(ctx.value).toString(16);
this.prestate[toHex(ctx.from)].balance = '0x'+fromBal.add(ctx.value).toString(16);
// Decrement the caller's nonce, and remove empty create targets
this.prestate[toHex(ctx.from)].nonce--;
if (ctx.type == 'CREATE') {
// We can blibdly delete the contract prestate, as any existing state would
// have caused the transaction to be rejected as invalid in the first place.
delete this.prestate[toHex(ctx.to)];
}
// Return the assembled allocations (prestate)
return this.prestate;
},
// step is invoked for every opcode that the VM executes.
step: function(log, db) {
// Add the current account if we just started tracing
if (this.prestate === null){
this.prestate = {};
// Balance will potentially be wrong here, since this will include the value
// sent along with the message. We fix that in 'result()'.
this.lookupAccount(log.contract.getAddress(), db);
}
// Whenever new state is accessed, add it to the prestate
switch (log.op.toString()) {
case "EXTCODECOPY": case "EXTCODESIZE": case "BALANCE":
this.lookupAccount(toAddress(log.stack.peek(0).toString(16)), db);
break;
case "CREATE":
var from = log.contract.getAddress();
this.lookupAccount(toContract(from, db.getNonce(from)), db);
break;
case "CALL": case "CALLCODE": case "DELEGATECALL": case "STATICCALL":
this.lookupAccount(toAddress(log.stack.peek(1).toString(16)), db);
break;
case 'SSTORE':case 'SLOAD':
this.lookupStorage(log.contract.getAddress(), toWord(log.stack.peek(0).toString(16)), db);
break;
}
},
// fault is invoked when the actual execution of an opcode fails.
fault: function(log, db) {}
}

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eth/tracers/internal/tracers/tracers.go Normal file
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// Copyright 2017 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
//go:generate go-bindata -nometadata -o assets.go -pkg tracers -ignore ((tracers)|(assets)).go ./...
//go:generate gofmt -s -w assets.go
// Package tracers contains the actual JavaScript tracer assets.
package tracers