Merge pull request #296 from python-cmd2/completion_tweaks

Completion tweaks

Author: tleonhardt

cmd2.py

@@ -165,7 +165,7 @@ def set_use_arg_list(val):
 
 def flag_based_complete(text, line, begidx, endidx, flag_dict, default_completer=None):
     """
-    Tab completes based on a particular flag preceding the text being completed
+    Tab completes based on a particular flag preceding the token being completed
     :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
@@ -181,15 +181,14 @@ def flag_based_complete(text, line, begidx, endidx, flag_dict, default_completer
     :return: List[str] - a list of possible tab completions
     """
 
-    # Get all tokens prior to text being completed
+    # Get all tokens prior to token being completed
     try:
         prev_space_index = max(line.rfind(' ', 0, begidx), 0)
         tokens = shlex.split(line[:prev_space_index], posix=POSIX_SHLEX)
     except ValueError:
         # Invalid syntax for shlex (Probably due to missing closing quote)
         return []
 
-    # Nothing to do
     if len(tokens) == 0:
         return []
 
@@ -199,7 +198,7 @@ def flag_based_complete(text, line, begidx, endidx, flag_dict, default_completer
     # Must have at least the command and one argument for a flag to be present
     if len(tokens) > 1:
 
-        # Get the argument that precedes the text being completed
+        # Get the argument that precedes the token being completed
         flag = tokens[-1]
 
         # Check if the flag is in the dictionary
@@ -242,12 +241,12 @@ def index_based_complete(text, line, begidx, endidx, index_dict, default_complet
                              values - there are two types of values
                                 1. iterable list of strings to match against (dictionaries, lists, etc.)
                                 2. function that performs tab completion (ex: path_complete)
-    :param default_completer: callable - an optional completer to use if the text being completed is not at
+    :param default_completer: callable - an optional completer to use if the token being completed is not at
                                          any index in index_dict
     :return: List[str] - a list of possible tab completions
     """
 
-    # Get all tokens prior to text being completed
+    # Get all tokens prior to token being completed
     try:
         prev_space_index = max(line.rfind(' ', 0, begidx), 0)
         tokens = shlex.split(line[:prev_space_index], posix=POSIX_SHLEX)
@@ -260,7 +259,7 @@ def index_based_complete(text, line, begidx, endidx, index_dict, default_complet
     # Must have at least the command
     if len(tokens) > 0:
 
-        # Get the index of the text being completed
+        # Get the index of the token being completed
         index = len(tokens)
 
         # Check if the index is in the dictionary
@@ -300,20 +299,32 @@ def path_complete(text, line, begidx, endidx, dir_exe_only=False, dir_only=False
     :return: List[str] - a list of possible tab completions
     """
 
+    # Get all tokens prior to token being completed
+    try:
+        prev_space_index = max(line.rfind(' ', 0, begidx), 0)
+        tokens = shlex.split(line[:prev_space_index], posix=POSIX_SHLEX)
+    except ValueError:
+        # Invalid syntax for shlex (Probably due to missing closing quote)
+        return []
+
+    if len(tokens) == 0:
+        return []
+
     # Determine if a trailing separator should be appended to directory completions
     add_trailing_sep_if_dir = False
     if endidx == len(line) or (endidx < len(line) and line[endidx] != os.path.sep):
         add_trailing_sep_if_dir = True
 
     add_sep_after_tilde = False
-    # If no path and no search text has been entered, then search in the CWD for *
-    if not text and line[begidx - 1] == ' ' and (begidx >= len(line) or line[begidx] == ' '):
+
+    # Readline places begidx after ~ and path separators (/) so we need to extract any directory
+    # path that appears before the search text
+    dirname = line[prev_space_index + 1:begidx]
+
+    # If no directory path and no search text has been entered, then search in the CWD for *
+    if not dirname and not text:
         search_str = os.path.join(os.getcwd(), '*')
     else:
-        # Parse out the path being searched
-        prev_space_index = line.rfind(' ', 0, begidx)
-        dirname = line[prev_space_index + 1:begidx]
-
         # Purposely don't match any path containing wildcards - what we are doing is complicated enough!
         wildcards = ['*', '?']
         for wildcard in wildcards:
@@ -354,7 +365,7 @@ def path_complete(text, line, begidx, endidx, dir_exe_only=False, dir_only=False
 
     # If there is a single completion
     if len(completions) == 1:
-        # If it is a file and we are at the end of the line, then add a space for convenience
+        # If it is a file and we are at the end of the line, then add a space
         if os.path.isfile(path_completions[0]) and endidx == len(line):
             completions[0] += ' '
         # If tilde was expanded without a separator, prepend one
@@ -1340,7 +1351,7 @@ def complete_help(self, text, line, begidx, endidx):
         Override of parent class method to handle tab completing subcommands
         """
 
-        # Get all tokens prior to text being completed
+        # Get all tokens prior to token being completed
         try:
             prev_space_index = max(line.rfind(' ', 0, begidx), 0)
             tokens = shlex.split(line[:prev_space_index], posix=POSIX_SHLEX)
@@ -2030,22 +2041,20 @@ def do_shell(self, command):
         proc = subprocess.Popen(command, stdout=self.stdout, shell=True)
         proc.communicate()
 
-    # noinspection PyUnusedLocal
     @staticmethod
-    def _shell_command_complete(text, line, begidx, endidx):
-        """Method called to complete an input line by environment PATH executable completion.
+    def _get_exes_in_path(starts_with, at_eol):
+        """
+        Called by complete_shell to get names of executables in a user's path
 
-        :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
+        :param starts_with: str - what the exes should start with
+        :param at_eol: bool - tells if the user's cursor is at the end of the command line
         :return: List[str] - a list of possible tab completions
         """
 
         # Purposely don't match any executable containing wildcards
         wildcards = ['*', '?']
         for wildcard in wildcards:
-            if wildcard in text:
+            if wildcard in starts_with:
                 return []
 
         # Get a list of every directory in the PATH environment variable and ignore symbolic links
@@ -2054,9 +2063,9 @@ def _shell_command_complete(text, line, begidx, endidx):
         # Use a set to store exe names since there can be duplicates
         exes = set()
 
-        # Find every executable file in the PATH that matches the pattern
+        # Find every executable file in the user's path that matches the pattern
         for path in paths:
-            full_path = os.path.join(path, text)
+            full_path = os.path.join(path, starts_with)
             matches = [f for f in glob.glob(full_path + '*') if os.path.isfile(f) and os.access(f, os.X_OK)]
 
             for match in matches:
@@ -2067,13 +2076,13 @@ def _shell_command_complete(text, line, begidx, endidx):
         results.sort()
 
         # If there is a single completion and we are at end of the line, then add a space at the end for convenience
-        if len(results) == 1 and endidx == len(line):
+        if len(results) == 1 and at_eol:
             results[0] += ' '
 
         return results
 
     def complete_shell(self, text, line, begidx, endidx):
-        """Handles tab completion of executable commands and local file system paths.
+        """Handles tab completion of executable commands and local file system paths for the shell 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
@@ -2082,15 +2091,14 @@ def complete_shell(self, text, line, begidx, endidx):
         :return: List[str] - a list of possible tab completions
         """
 
-        # Get all tokens prior to text being completed
+        # Get all tokens prior to token being completed
         try:
             prev_space_index = max(line.rfind(' ', 0, begidx), 0)
             tokens = shlex.split(line[:prev_space_index], posix=POSIX_SHLEX)
         except ValueError:
             # Invalid syntax for shlex (Probably due to missing closing quote)
             return []
 
-        # Nothing to do
         if len(tokens) == 0:
             return []
 
@@ -2106,19 +2114,19 @@ def complete_shell(self, text, line, begidx, endidx):
             if len(cmd_token) == 0:
                 return []
 
+            # Look for path characters in the token
             if not (cmd_token.startswith('~') or os.path.sep in cmd_token):
                 # No path characters are in this token, it is OK to try shell command completion.
-                command_completions = self._shell_command_complete(text, line, begidx, endidx)
+                command_completions = self._get_exes_in_path(text, endidx == len(line))
 
                 if command_completions:
                     return command_completions
 
             # If we have no results, try path completion to find the shell commands
             return path_complete(text, line, begidx, endidx, dir_exe_only=True)
 
-        # Shell command has been completed
+        # We are past the shell command, so do path completion
         else:
-            # Do path completion
             return path_complete(text, line, begidx, endidx)
 
     # noinspection PyBroadException

tests/test_completion.py

@@ -379,6 +379,25 @@ def test_path_completion_directories_only(request):
 
     assert path_complete(text, line, begidx, endidx, dir_only=True) == ['scripts' + os.path.sep]
 
+def test_path_completion_syntax_err(request):
+    test_dir = os.path.dirname(request.module.__file__)
+
+    text = 'c'
+    path = os.path.join(test_dir, text)
+    line = 'shell cat " {}'.format(path)
+
+    endidx = len(line)
+    begidx = endidx - len(text)
+
+    assert path_complete(text, line, begidx, endidx) == []
+
+def test_path_completion_no_tokens():
+    text = ''
+    line = 'shell'
+    endidx = len(line)
+    begidx = endidx - len(text)
+    assert path_complete(text, line, begidx, endidx) == []
+
 
 # List of strings used with flag and index based completion functions
 food_item_strs = ['Pizza', 'Hamburger', 'Ham', 'Potato']
@@ -457,6 +476,15 @@ def test_flag_based_completion_syntax_err():
 
     assert flag_based_complete(text, line, begidx, endidx, flag_dict) == []
 
+def test_flag_based_completion_no_tokens():
+    text = ''
+    line = 'list_food'
+    endidx = len(line)
+    begidx = endidx - len(text)
+
+    assert flag_based_complete(text, line, begidx, endidx, flag_dict) == []
+
+
 # Dictionary used with index based completion functions
 index_dict = \
     {