start throwing errors when file doesn't exist

index.js

@@ -1,3 +1,5 @@
+var fs               = require('fs')
+
 function Play(opts){
   var opts = opts || {}
 
@@ -9,6 +11,7 @@ function Play(opts){
 
   this.play = function(what){
     if (!what) return;
+    if (!fs.existsSync(what)) throw new Error("Couldn't find file: " + what)
 
     var players = this.players,
         self    = this

package.json

@@ -24,6 +24,7 @@
   "devDependencies": {
     "expect.js": "^0.3.1",
     "mocha": "^1.21.4",
+    "mock-fs": "^2.3.1",
     "sinon": "^1.10.3"
   }
 }

tests.js

@@ -1,15 +1,20 @@
 var expect = require('expect.js')
   , sinon  = require('sinon')
+  , mock   = require('mock-fs')
 
 
 describe('cvlc has the maximum priority', function(){
-  it('tries to play with cvlc first', function(){
-    var command = "cvlc beep.mp3"
-      , spy     = sinon.stub()
+  var command, spy, cli;
 
-    var cli = require('./')({ child_process: {
-      exec: spy
-    }})
+  beforeEach(function(){
+    command = "cvlc beep.mp3"
+    , spy     = sinon.stub()
+    , cli = require('./')({ child_process: { exec: spy }})
+
+    mock({'./beep.mp3': ''})
+  })
+
+  it('tries to play with cvlc first', function(){
     spy.callsArg(1)
 
     cli.play("beep.mp3")
@@ -20,31 +25,37 @@ describe('cvlc has the maximum priority', function(){
   })
 
   it("doesn't try to play anything if nothing is passed", function(){
-    var command = "cvlc beep.mp3"
-      , spy     = sinon.spy()
-
-    var cli = require('./')({ child_process: spy})
     cli.play()
 
     expect(spy.called).to.not.be(true)
   })
 
   it("fallbacks to other players if it's not available", function(){
-    var command = "cvlc beep.mp3"
-      , spy     = sinon.stub()
-
-    var cli = require('./')({ child_process: {
-      exec: spy
-    }})
     spy.callsArg(1)
     spy.withArgs("cvlc beep.mp3").callsArgWith(1, "cvlc: command not found")
 
     cli.play("beep.mp3")
     expect(cli.player).to.be("mplayer")
   })
+
+  after(function(){
+    mock.restore()
+  })
 })
 
 describe('error handling', function(){
-  it("throws errors if file doesn't exist")
+  it("throws errors if the file doesn't exist", function(){
+    var stub = sinon.stub()
+      , cli  = require('./')({ child_process: {exec: stub}})
+
+    expect(cli.play).withArgs("beep.mp3").to.throwException()
+  })
+
   it("throws errors if suitable audio tool couldn't be found")
 })
+
+describe("overridable options", function(){
+  it("supports overrides for the list of players")
+  it("supports override for child_process")
+  it("supports override for player")
+})