Open http/https links in an external browser

Listen for all links being clicked and open any http/https
hrefs by spawning a call to the 'open' command.

Closes #531

spec/app/window-spec.coffee

@@ -230,3 +230,25 @@ describe "Window", ->
         event = buildDragEvent("drop", [])
         window.onDrop(event)
         expect(atom.open).not.toHaveBeenCalled()
+
+  describe "when a link is clicked", ->
+    it "opens the http/https links in an external application", ->
+      ChildProcess = require 'child_process'
+      spyOn(ChildProcess, 'spawn')
+
+      $("<a href='http://github.com'>the website</a>").appendTo(document.body).click().remove()
+      expect(ChildProcess.spawn).toHaveBeenCalled()
+      expect(ChildProcess.spawn.argsForCall[0][1][0]).toBe "http://github.com"
+
+      ChildProcess.spawn.reset()
+      $("<a href='https://github.com'>the website</a>").appendTo(document.body).click().remove()
+      expect(ChildProcess.spawn).toHaveBeenCalled()
+      expect(ChildProcess.spawn.argsForCall[0][1][0]).toBe "https://github.com"
+
+      ChildProcess.spawn.reset()
+      $("<a href=''>the website</a>").appendTo(document.body).click().remove()
+      expect(ChildProcess.spawn).not.toHaveBeenCalled()
+
+      ChildProcess.spawn.reset()
+      $("<a href='#scroll-me'>link</a>").appendTo(document.body).click().remove()
+      expect(ChildProcess.spawn).not.toHaveBeenCalled()

src/app/window.coffee

@@ -27,6 +27,15 @@ window.setUpEnvironment = ->
   window.pasteboard = new Pasteboard
   window.keymap = new Keymap()
   $(document).on 'keydown', keymap.handleKeyEvent
+
+  $(document).on 'click', 'a', (e) ->
+    location = $(e.target).attr('href')
+    return unless location or location[0] is '#'
+
+    if location.indexOf('https://') is 0 or location.indexOf('http://') is 0
+      require('child_process').spawn('open', [location]) if location
+    false
+
   keymap.bindDefaultKeys()
 
   requireStylesheet 'atom'