Updated an example, features, and changes based on new support for path and command completion

Author: tleonhardt

CHANGES.md

@@ -22,6 +22,7 @@ News
     * Example of how to use regular expressions in a transcript test
 * Added CmdResult namedtumple for returning and storing results
 * Added local file system path completion for ``edit``, ``load``, ``save``, and ``shell`` commands
+* Add shell command completion for ``shell`` command or ``!`` shortcut
 
 0.7.0
 -----

README.md

@@ -35,6 +35,7 @@ cmd2 provides the following features, in addition to those already existing in c
 - Pipe output to shell commands with `|`
 - Simple transcript-based application testing
 - Unicode character support (*Python 3 only*)
+- Path completion for ``edit``, ``load``, ``save``, and ``shell`` commands
 
 Instructions for implementing each feature follow.
 

cmd2.py

@@ -82,6 +82,7 @@
 # Try to import readline, but allow failure for convenience in Windows unit testing
 # Note: If this actually fails, you should install readline on Linux or Mac or pyreadline on Windows
 try:
+    # noinspection PyUnresolvedReferences
     import readline
 except ImportError:
     pass
@@ -479,6 +480,7 @@ class StubbornDict(dict):
 
     Create it with the stubbornDict(arg) factory function.
     """
+    # noinspection PyMethodOverriding
     def update(self, arg):
         """Adds dictionary arg's key-values pairs in to dict
 
@@ -930,11 +932,11 @@ def precmd(self, statement):
         return statement
 
     def parseline(self, line):
-        """Parse the line into a command name and a string containing the arguments.  
-        
+        """Parse the line into a command name and a string containing the arguments.
+
         Used for command tab completion.  Returns a tuple containing (command, args, line).
         'command' and 'args' may be None if the line couldn't be parsed.
-        
+
         :param line: str - line read by readline
         :return: (str, str, str) - tuple containing (command, args, line)
         """
@@ -1354,14 +1356,15 @@ def help_shell(self):
     Usage:  shell cmd"""
         self.stdout.write("{}\n".format(help_str))
 
-    def path_complete(self, text, line, begidx, endidx, dir_exe_only=False):
+    def path_complete(self, text, line, begidx, endidx, dir_exe_only=False, dir_only=False):
         """Method called to complete an input line by local file system path completion.
 
         :param text: str - the string prefix we are attempting to match (all returned matches must begin with it)
         :param line: str - the current input line with leading whitespace removed
         :param begidx: int - the beginning indexe of the prefix text
         :param endidx: int - the ending index of the prefix text
         :param dir_exe_only: bool - only return directories and executables, not non-executable files
+        :param dir_only: bool - only return directories
         :return: List[str] - a list of possible tab completions
         """
         # Deal with cases like load command and @ key when path completion is immediately after a shortcut
@@ -1413,6 +1416,8 @@ def path_complete(self, text, line, begidx, endidx, dir_exe_only=False):
         # If we only want directories and executables, filter everything else out first
         if dir_exe_only:
             path_completions = [c for c in path_completions if os.path.isdir(c) or os.access(c, os.X_OK)]
+        elif dir_only:
+            path_completions = [c for c in path_completions if os.path.isdir(c)]
 
         # Get the basename of the paths
         completions = []
@@ -1446,7 +1451,7 @@ def _shell_command_complete(search_text):
         """Method called to complete an input line by environment PATH executable completion.
 
         :param search_text: str - the search text used to find a shell command
-        :return: List[str] - a list of possible tab completions 
+        :return: List[str] - a list of possible tab completions
         """
 
         # Purposely don't match any executable containing wildcards
@@ -1478,7 +1483,7 @@ def _shell_command_complete(search_text):
     def complete_shell(self, text, line, begidx, endidx):
         """Handles tab completion of executable commands and local file system paths.
 
-        :param text: str - the string prefix we are attempting to match (all returned matches must begin with it) 
+        :param text: str - the string prefix we are attempting to match (all returned matches must begin with it)
         :param line: str - the current input line with leading whitespace removed
         :param begidx: int - the beginning index of the prefix text
         :param endidx: int - the ending index of the prefix text

examples/python_scripting.py

@@ -14,6 +14,7 @@
 
 This application and the "script_conditional.py" script serve as an example for one way in which this can be done.
 """
+import functools
 import os
 
 from cmd2 import Cmd, options, make_option, CmdResult, set_use_arg_list
@@ -35,7 +36,6 @@ def __init__(self):
     def _set_prompt(self):
         """Set prompt so it displays the current working directory."""
         self.cwd = os.getcwd()
-        self.subdirs = [d for d in os.listdir(self.cwd) if os.path.isdir(d)]
         self.prompt = '{!r} $ '.format(self.cwd)
 
     def postcmd(self, stop, line):
@@ -83,17 +83,8 @@ def do_cd(self, arg, opts=None):
             self.perror(err, traceback_war=False)
         self._last_result = CmdResult(out, err)
 
-    # noinspection PyUnusedLocal
-    def complete_cd(self, text, line, begidx, endidx):
-        """Handles completion of arguments for the cd command.
-
-        :param text: str - the string prefix we are attempting to match (all returned matches must begin with it)
-        :param line: str - the current input line with leading whitespace removed
-        :param begidx: str - the beginning indexe of the prefix text
-        :param endidx: str - the ending index of the prefix text
-        :return: List[str] - a list of possible tab completions
-        """
-        return [d for d in self.subdirs if d.startswith(text)]
+    # Enable directory completion for cd command by freezing an argument to path_complete() with functools.partialmethod
+    complete_cd = functools.partialmethod(Cmd.path_complete, dir_only=True)
 
     @options([make_option('-l', '--long', action="store_true", help="display in long format with one item per line")],
              arg_desc='')