Added 1 check for EDITOR var, if EDITOR is set to "" + added try catch to catch subprocess error like EDITOR variable pointing to a non installed editor

cheat

@@ -69,7 +69,7 @@ class CheatSheets(object):
         if not self.dirs:
             error_msg = 'The {default} dir does not exist or the CHEATPATH var is not set.'
             print >> sys.stderr, error_msg.format(default=DEFAULT_CHEAT_DIR)
-            exit()
+            exit(1)
         self.sheets = self.__cheat_files()
 
     def __cheat_directories(self):
@@ -106,12 +106,19 @@ class CheatSheets(object):
         # Assert that the EDITOR environment variable is set and that at least 3
         # arguments have been given
         if 'EDITOR' not in os.environ:
-            print('In order to use "create" or "edit" you must set your '
-                  'EDITOR environment variable to your favorite editor\'s path')
-            exit()
+            print >> sys.stderr, ('In order to create/edit a cheatsheet you '
+                'must set your EDITOR environment variable to your favorite '
+                'editor\'s path.')
+            exit(1)
+        elif os.environ['EDITOR'] == "":
+            print >> sys.stderr, ('Your EDITOR environment variable is set '
+                'to nothing, in order to create/edit a cheatsheet your must '
+                'set it to a valid editor\'s path.')
+            exit(1)
         else:
             editor = os.environ['EDITOR'].split()
         # if the cheatsheet already exists, open it for editing
+        try:
             if cheat in sheets.sheets:
                 subprocess.call(editor + [os.path.join(self.sheets[cheat], cheat)])
 
@@ -127,6 +134,10 @@ class CheatSheets(object):
                 # directory, though that will likely require the use of sudo
                 else:
                     subprocess.call(editor + [os.path.join(cs.cheat_dir, cheat)])
+        except OSError, e:
+            print >> sys.stderr, ("Could not launch `%s` as your editor : %s"
+                                  % (editor[0], e.strerror))
+            exit(1)
 
     def list(self):
         """Lists the cheatsheets that are currently available"""