Node.js Javascript / CoffeeScript Stack Trace Obj with line from code

main.coffee

StackObjError = require "stack_trace_with_line_from_code"

first_func = ->
  second_func = ->
    console.log JSON.stringify(new StackObjError().stack)
  second_func()
first_func()

output.json

[
  {
    "where": "second_func",
    "file": "/home/user/test/main.coffee",
    "row": "49",
    "col": "41",
    "code": "      return console.log(JSON.stringify(new StackObjError().stack));"
  },
  {
    "where": "first_func",
    "file": "/home/user/test/main.coffee",
    "row": "51",
    "col": "12",
    "code": "    return second_func();"
  },
  {
    "where": "Object.<anonymous>",
    "file": "/home/user/test/main.coffee",
    "row": "54",
    "col": "3",
    "code": "  first_func();"
  },
  {
    "where": "Object.<anonymous>",
    "file": "/home/user/test/main.coffee",
    "row": "105",
    "col": "4",
    "code": "}).call(this);"
  },
  { "where": "Module._compile", "file": "module.js", "row": "449", "col": "26" },
  {
    "where": "Object.exports.run",
    "file": "/opt/local/lib/node_modules/coffee-script/lib/coffee-script/coffee-script.js",
    "row": "83",
    "col": "25",
    "code": "      return mainModule._compile(compile(code, options), mainModule.filename);"
  },
  {
    "where": "compileScript",
    "file": "/opt/local/lib/node_modules/coffee-script/lib/coffee-script/command.js",
    "row": "177",
    "col": "29",
    "code": "        return CoffeeScript.run(t.input, t.options);"
  },
  "    at fs.stat.notSources.(anonymous function) (/opt/local/lib/node_modules/coffee-script/lib/coffee-script/command.js:152:18)"
]

stack_trace_with_line_from_code.coffee

CoffeeScript = require "coffee-script"
_ = require "underscore"
fs = require "fs"

coffeeFile2js = _.memoize (filename) ->
  CoffeeScript.compile \
    fs.readFileSync(filename, "utf-8")

jsFile = _.memoize (filename) -> 
  fs.readFileSync(filename, "utf-8")

StackObjError = ->
  err = Error.apply @, arguments
  @__defineGetter__ "stack", ->
    #console.log err.stack
    _(err.stack.split(/\n/)[3..-1]).map (trace) ->
      if matches =  trace.match /at ([^\(]+) \(([^:]+):(\d+):(\d+)\)/
        #console.log "file #{matches[2]}, line #{matches[3]}, col #{matches[4]}"
        trace = 
          where: matches[1]
          file: matches[2]
          row: matches[3]
          col: matches[4]
        if fs.existsSync trace.file
          trace.code = (
              if trace.file.match /\.coffee/
                coffeeFile2js trace.file
              else if trace.file
                jsFile trace.file
            ).split(/\n/)[trace.row - 1]

      trace
StackObjError:: = new StackObjError()
StackObjError::constructor = StackObjError
StackObjError::name = "StackObjError"

module.exports = StackObjError