Merge pull request #72 from python-cmd2/shlex

Miscellaneous code cleanup

1 files changed, 59 insertions, 15 deletions

diff --git a/cmd2.py b/cmd2.py
index 5ad6bf40..5ef4fe8e 100755
--- a/cmd2.py
+++ b/cmd2.py
@@ -59,11 +59,13 @@ import six.moves as sm
 from six.moves import zip
 
 # Python 2 urllib2.urlopen() or Python3  urllib.request.urlopen()
+# noinspection PyUnresolvedReferences
 from six.moves.urllib.request import urlopen
 
 # Python 3 compatability hack due to no built-in file keyword in Python 3
 # Due to one occurence of isinstance(<foo>, file) checking to see if something is of file type
 try:
+    # noinspection PyUnboundLocalVariable,PyUnresolvedReferences
     file
 except NameError:
     import io
@@ -72,6 +74,7 @@ except NameError:
 # Detect whether IPython is installed to determine if the built-in "ipy" command should be included
 ipython_available = True
 try:
+    # noinspection PyUnresolvedReferences
     from IPython import embed
 except ImportError:
     ipython_available = False
@@ -124,6 +127,16 @@ def set_use_arg_list(val):
 
 
 class OptionParser(optparse.OptionParser):
+    """Subclase of optparse.OptionParser which stores a reference to the function/method it is parsing options for.
+    
+    Used mostly for getting access to the do_* method's docstring when printing help.
+    """
+    def __init__(self):
+        # Call super class constructor.  Need to do it in this way for Python 2 and 3 compatibility
+        optparse.OptionParser.__init__(self)
+        # The do_* method this class is parsing options for.  Used for accessing docstring help.
+        self._func = None
+
     def exit(self, status=0, msg=None):
         self.values._exit = True
         if msg:
@@ -303,6 +316,7 @@ can_clip = False
 if sys.platform == "win32":
     # Running on Windows
     try:
+        # noinspection PyUnresolvedReferences
         import win32clipboard
 
         def get_paste_buffer():
@@ -388,6 +402,13 @@ pyparsing.ParserElement.setDefaultWhitespaceChars(' \t')
 
 
 class ParsedString(str):
+    """Subclass of str which also stores a pyparsing.ParseResults object containing structured parse results."""
+    # pyarsing.ParseResults - structured parse results, to provide multiple means of access to the parsed data
+    parsed = None
+
+    # Function which did the parsing
+    parser = None
+
     def full_parsed_statement(self):
         new = ParsedString('%s %s' % (self.parsed.command, self.parsed.args))
         new.parsed = self.parsed
@@ -514,7 +535,6 @@ class Cmd(cmd.Cmd):
     default_to_shell = False
     defaultExtension = 'txt'  # For ``save``, ``load``, etc.
     excludeFromHistory = '''run r list l history hi ed edit li eof'''.split()
-    kept_state = None
     # make sure your terminators are not in legalChars!
     legalChars = u'!#$%.:?@_-' + pyparsing.alphanums + pyparsing.alphas8bit
     multilineCommands = []
@@ -524,7 +544,7 @@ class Cmd(cmd.Cmd):
     reserved_words = []
     shortcuts = {'?': 'help', '!': 'shell', '@': 'load', '@@': '_relative_load'}
     terminators = [';']
-    urlre = re.compile('(https?://[-\\w\\./]+)')
+    urlre = re.compile('(https?://[-\\w./]+)')
 
     # Attributes which ARE dynamicaly settable at runtime
     abbrev = True  # Abbreviated commands recognized
@@ -589,11 +609,11 @@ class Cmd(cmd.Cmd):
         self.initial_stdout = sys.stdout
         self.history = History()
         self.pystate = {}
+        # noinspection PyUnresolvedReferences
         self.shortcuts = sorted(self.shortcuts.items(), reverse=True)
         self.keywords = self.reserved_words + [fname[3:] for fname in dir(self)
                                                if fname.startswith('do_')]
         self._init_parser()
-        self._temp_filename = None
         self._transcript_files = transcript_files
 
         # Used to enable the ability for a Python script to quit the application
@@ -606,6 +626,13 @@ class Cmd(cmd.Cmd):
         # Built-in commands don't make use of this.  It is purely there for user-defined commands and convenience.
         self._last_result = None
 
+        # Used to save state during a redirection
+        self.kept_state = None
+        self.kept_sys = None
+
+        # Used for a temp file during a pipe (needed tempfile instead of real pipe for Python 3.x prior to 3.5)
+        self._temp_filename = None
+
     def poutput(self, msg):
         """Convenient shortcut for self.stdout.write(); adds newline if necessary."""
         if msg:
@@ -748,18 +775,23 @@ class Cmd(cmd.Cmd):
             pyparsing.Optional(fileName) + (pyparsing.stringEnd | '|')
         self.inputParser.ignore(self.commentInProgress)
 
-    def preparse(self, raw, **kwargs):
+    def preparse(self, raw):
         return raw
 
     def postparse(self, parseResult):
         return parseResult
 
-    def parsed(self, raw, **kwargs):
+    def parsed(self, raw):
+        """ This function is where the actual parsing of each line occurs.
+        
+        :param raw: str - the line of text as it was entered
+        :return: ParsedString - custom subclass of str with extra attributes
+        """
         if isinstance(raw, ParsedString):
             p = raw
         else:
             # preparse is an overridable hook; default makes no changes
-            s = self.preparse(raw, **kwargs)
+            s = self.preparse(raw)
             s = self.inputParser.transformString(s.lstrip())
             s = self.commentGrammars.transformString(s)
             for (shortcut, expansion) in self.shortcuts:
@@ -777,8 +809,6 @@ class Cmd(cmd.Cmd):
             p = ParsedString(result.args)
             p.parsed = result
             p.parser = self.parsed
-        for (key, val) in kwargs.items():
-            p.parsed[key] = val
         return p
 
     def postparsing_precmd(self, statement):
@@ -981,6 +1011,7 @@ class Cmd(cmd.Cmd):
         # has been split out so that it can be called separately
         if self.use_rawinput and self.completekey:
             try:
+                # noinspection PyUnresolvedReferences
                 import readline
                 self.old_completer = readline.get_completer()
                 readline.set_completer(self.complete)
@@ -1000,6 +1031,7 @@ class Cmd(cmd.Cmd):
         finally:
             if self.use_rawinput and self.completekey:
                 try:
+                    # noinspection PyUnresolvedReferences
                     import readline
                     readline.set_completer(self.old_completer)
                 except ImportError:
@@ -1514,6 +1546,7 @@ Script should contain one command per line, just like command would be typed in
                 return self._STOP_AND_EXIT
 
     def cmdloop(self, intro=None):
+        callargs = None
         if self.allow_cli_args:
             parser = optparse.OptionParser()
             parser.add_option('-t', '--test', dest='test',
@@ -1578,6 +1611,15 @@ class History(list):
         return result
 
     def search(self, target):
+        """ Search the history for a particular term.
+        
+        :param target: str - term to search for
+        :return: List[str] - list of matches
+        """
+        # If there is no history yet, don't try to search through a non-existent list, just return an empty list
+        if len(self) < 1:
+            return []
+
         target = target.strip()
         if target[0] == target[-1] == '/' and len(target) > 1:
             target = target[1:-1]
@@ -1586,7 +1628,7 @@ class History(list):
         pattern = re.compile(target, re.IGNORECASE)
         return [s for s in self if pattern.search(s)]
 
-    spanpattern = re.compile(r'^\s*(?P<start>\-?\d+)?\s*(?P<separator>:|(\.{2,}))?\s*(?P<end>\-?\d+)?\s*$')
+    spanpattern = re.compile(r'^\s*(?P<start>-?\d+)?\s*(?P<separator>:|(\.{2,}))?\s*(?P<end>-?\d+)?\s*$')
 
     def span(self, raw):
         if raw.lower() in ('*', '-', 'all'):
@@ -1609,7 +1651,7 @@ class History(list):
             result.reverse()
         return result
 
-    rangePattern = re.compile(r'^\s*(?P<start>[\d]+)?\s*\-\s*(?P<end>[\d]+)?\s*$')
+    rangePattern = re.compile(r'^\s*(?P<start>[\d]+)?\s*-\s*(?P<end>[\d]+)?\s*$')
 
     def append(self, new):
         new = HistoryItem(new)
@@ -1642,6 +1684,7 @@ class History(list):
                     end = int(end)
                 return self[start:end]
 
+            # noinspection PyUnresolvedReferences
             getme = getme.strip()
 
             if getme.startswith(r'/') and getme.endswith(r'/'):
@@ -1702,19 +1745,19 @@ class Statekeeper(object):
 
 
 class Borg(object):
-    '''All instances of any Borg subclass will share state.
-    from Python Cookbook, 2nd Ed., recipe 6.16'''
+    """All instances of any Borg subclass will share state.
+    from Python Cookbook, 2nd Ed., recipe 6.16"""
     _shared_state = {}
 
     def __new__(cls, *a, **k):
-        obj = object.__new__(cls, *a, **k)
+        obj = object.__new__(cls)
         obj.__dict__ = cls._shared_state
         return obj
 
 
 class OutputTrap(Borg):
-    '''Instantiate  an OutputTrap to divert/capture ALL stdout output.  For use in unit testing.
-    Call `tearDown()` to return to normal output.'''
+    """Instantiate  an OutputTrap to divert/capture ALL stdout output.  For use in unit testing.
+    Call `tearDown()` to return to normal output."""
 
     def __init__(self):
         self.contents = ''
@@ -1855,4 +1898,5 @@ class CmdResult(namedtuple('CmdResult', ['out', 'err', 'war'])):
 if __name__ == '__main__':
     # If run as the main application, simply start a bare-bones cmd2 application with only built-in functionality.
     app = Cmd()
+    app.debug = True
     app.cmdloop()