[FIX] Uncaught TypeError: Cannot read property 'focus' of null

[JohnAtFenestra]

This is a suggested fix to an error which turned up for me on May 20, 2016. The error was originally documented as #1 Uncaught TypeError: Cannot read property 'focus' of null. I posted this suggested fix as a comment before I realized that the issue had been closed.

I looked over the code and it may be a race condition. The use case scenario would be one where handleFocus is called a second time before @returnFocus is set to null. The final scenario, which is highly unlikely, involves both threads passing the first guard and then thread one switching and setting @returnFocus to null before the second thread assigns to a temp variable. I added a final guard for that possibility as well.

Suggested change:

status-bar.coffee

Original

    handleFocus = =>
      if @returnFocus
        setTimeout =>
            @returnFocus.focus()
            @returnFocus = null
        , 100

Changed

    handleFocus = =>
      if @returnFocus
        setTimeout =>
          if @returnFocus
              tempFocus = @returnFocus
              @returnFocus = null
              tempFocus.focus() if tempFocus
        , 100

[fusion809]

@JohnAtFenestra Hi, while it seems that Jeremyramin is unlikely to respond to this issue anytime soon as he hasn't been on GitHub for several months now, I have just implemented this fix at my repo. So if you want to use a terminal package with this fix please use it. You can install it by running:

apm install terminal-fusion