块菌调试器:TypeError:无法读取未定义的属性“line”

我正在尝试使用Truffle 4.1.0调试Solidity代码。 调试器正确启动,显示第一行,但您不能单步执行契约!

终端上显示的错误的完整堆栈跟踪是:

 TypeError: Cannot read property 'line' of undefined
     at Object.formatRangeLines (/usr/local/lib/node_modules/truffle/build/webpack:/~/truffle-debug-utils/index.js:201:1)
     at printState (/usr/local/lib/node_modules/truffle/build/webpack:/~/truffle-core/lib/commands/debug.js:125:1)
     at Object.interpreter (/usr/local/lib/node_modules/truffle/build/webpack:/~/truffle-core/lib/commands/debug.js:404:1)
     at ReplManager.interpret (/usr/local/lib/node_modules/truffle/build/webpack:/~/truffle-core/lib/repl.js:119:1)
     at bound (domain.js:280:14)
     at REPLServer.runBound [as eval] (domain.js:293:12)
     at REPLServer.<anonymous> (repl.js:539:10)
     at emitOne (events.js:96:13)
     at REPLServer.emit (events.js:188:7)
     at REPLServer.Interface._onLine (readline.js:232:10)
     at REPLServer.Interface._line (readline.js:583:8)
     at REPLServer.Interface._ttyWrite (readline.js:860:14)
     at REPLServer.self._ttyWrite (repl.js:612:7)
     at ReadStream.onkeypress (readline.js:119:10)
     at emitTwo (events.js:106:13)
     at ReadStream.emit (events.js:191:7)
     at emitKeys (internal/readline.js:389:14)
     at next (native)
     at ReadStream.onData (readline.js:970:36)
     at emitOne (events.js:96:13)
     at ReadStream.emit (events.js:188:7)
     at readableAddChunk (_stream_readable.js:176:18)
     at ReadStream.Readable.push (_stream_readable.js:134:10)
     at TTY.onread (net.js:547:20)

挖掘方法 formatRangeLines: function(source, range, contextBefore) 什么时候 console.log(range); 它打印:

{ start: undefined, end: undefined }

实际上,访问时引发的异常 range.start 在该街区:

var startBeforeIndex = Math.max(
  range.start.line - contextBefore, 0
);

有什么建议吗? 谢谢