sparkio-led.js

var five = require("johnny-five");
var Spark = require("spark-io");

var board = new five.Board({
  io: new Spark({
    token: process.env.SPARK_TOKEN,
    deviceId: process.env.SPARK_DEVICE_ID
  })
});

board.on("ready", function() {

  var led = new five.Led(process.argv[2] || "D7");

  this.repl.inject({
    led: led
  });
});

Throws error from spark.js:

$ node led.js "A1"
1400640461861 Device(s) spark-io 
1400640462615 Connected spark-io 
1400640462615 Repl Initialized 
>> 
/Users/Resseguie/Dropbox/work/spark-io/lib/spark.js:276
  pinInt = (pin.replace(/A|D/, "") | 0) + offset;
                ^
TypeError: Object 1 has no method 'replace'
    at Spark.pinMode (/Users/Resseguie/Dropbox/work/spark-io/lib/spark.js:276:17)
    at Led.Object.defineProperties.mode.set (/Users/Resseguie/Dropbox/work/spark-io/node_modules/johnny-five/lib/led.js:83:19)
    at new Led (/Users/Resseguie/Dropbox/work/spark-io/node_modules/johnny-five/lib/led.js:97:15)
    at Board.<anonymous> (/Users/Resseguie/Dropbox/work/spark-io/eg/led.js:13:13)
    at Board.EventEmitter.emit (events.js:95:17)
    at Board.broadcast (/Users/Resseguie/Dropbox/work/spark-io/node_modules/johnny-five/lib/board.js:384:8)
    at Board.<anonymous> (/Users/Resseguie/Dropbox/work/spark-io/node_modules/johnny-five/lib/board.js:298:23)
    at Spark.g (events.js:180:16)
    at Spark.EventEmitter.emit (events.js:92:17)
    at Socket.<anonymous> (/Users/Resseguie/Dropbox/work/spark-io/lib/spark.js:183:13)

I added a couple debug statements and pin is of type number, mode == 1.