Fixes #99. Removes ancient readline and custom tab completion code in favor of native + std rlcompleter.

seash.py

@@ -57,45 +57,27 @@
 # Needed for parsing user commands and executing command functions
 import seash_dictionary
 
-# We need to expose the readline object file to OSX because the default object
-# file for Python 2.7 on OSX is not compatible with our tab completion module.
 import os
-import sys
-
-# Only rename if we're running on OSX
-rename_readline_so_file = sys.platform == 'darwin'
-HIDDEN_READLINE_SO_FN = 'readline.so.mac'
-EXPOSED_READLINE_SO_FN = 'readline.so'
-
-# Make sure we don't overwrite an existing readline.so if it exists.
-# We need to do this because os.rename() doesn't raise any errors
-# if the destination file already exists.
-if (rename_readline_so_file and 
-    EXPOSED_READLINE_SO_FN not in os.listdir('.')):
-  try:
-    os.rename(HIDDEN_READLINE_SO_FN, EXPOSED_READLINE_SO_FN)
-  except OSError:
-    # There was a problem reading readline.so.mac
-    rename_readline_so_file = False
-
-tabcompletion = True
-try:
-  try:
-    # Required for windows tab-completion. 
-    # This is the readline module provided by pyreadline 1.7.1.
-    # http://pypi.python.org/pypi/pyreadline
+
+tabcompletion = True # By default, we should have tab completion on.
+
+# Next, we import readline, which we use for command-line editing
+# within seash.
+try: # Try importing readline and then rlcompleter if that is successful.
+  try: # Try importing packaged Windows version of readline first.
     import readline_windows as readline
   except ImportError:
-    # This error occurs when trying to import win_readline on mac/linux.
-    # We use the default readline module for mac/linux.
+    # Nope, not windows (presumably)
+    # Try whatever readline is immediately available in the environment.
     import readline
-  import tab_completer
-except ImportError:
+
+  # If we managed to import one or the other readline,
+  # import standard rlcompleter module to provide tab completion
+  # support for directories and files.
+  import rlcompleter
+except ImportError: # If all readline imports fail or rlcompleter import failed
   tabcompletion = False
-
-# Don't hide mac readline.so if we didn't expose it
-if rename_readline_so_file:
-  os.rename(EXPOSED_READLINE_SO_FN, HIDDEN_READLINE_SO_FN)
+
 
 # Used for re-enabling modules on the last run
 import seash_modules
@@ -143,17 +125,14 @@ def command_loop(test_command_list):
 
   # Set up the tab completion environment (Added by Danny Y. Huang)
   if tabcompletion:
-    # Initializes seash's tab completer
-    completer = tab_completer.Completer()
+    readline.parse_and_bind("bind ^I rl_complete")
     readline.parse_and_bind("tab: complete")
     # Determines when a new tab complete instance should be initialized,
     # which, in this case, is never, so the tab completer will always take
     # the entire user's string into account
     readline.set_completer_delims("")
-    # Sets the completer function that readline will utilize
-    readline.set_completer(completer.complete)
   else:
-    warnings.warn("Auto tab completion is off, because it is not available on your operating system.",ImportWarning)
+    warnings.warn("Auto tab completion is off, because it is not available on your operating system.", ImportWarning)
 
 
   # If passed a list of commands, do not prompt for user input
@@ -197,11 +176,6 @@ def command_loop(test_command_list):
   else:
     while True:
       try:
-        if tabcompletion:
-          # Updates the list of variable values in the tab complete class
-          completer.set_target_list()
-          completer.set_keyname_list()
-
         # Saving state after each command? (Added by Danny Y. Huang)
         if environment_dict['autosave'] and environment_dict['defaultkeyname']:
           try: