Utility Functions

def debug(*args) -> None:
    """
    Print debug information when _ARC_DEBUG environment variable is set.
    
    Parameters:
    - *args: Arguments to print to debug stream
    
    Note: Only outputs when _ARC_DEBUG environment variable is present
    """

def warn(*args) -> None:
    """
    Print warning messages to stderr during completion.
    
    Parameters:
    - *args: Warning messages to display
    
    This interrupts the user's command line interaction and should only
    be used to indicate error conditions preventing completion.
    """

# Enable debug output
export _ARC_DEBUG=1
my-script --<TAB>  # Shows debug information

# In custom completers
from argcomplete import debug, warn

class MyCompleter(BaseCompleter):
    def __call__(self, prefix, **kwargs):
        debug("MyCompleter called with prefix:", prefix)
        
        try:
            completions = self._get_completions(prefix)
            debug("Generated completions:", completions)
            return completions
        except Exception as e:
            warn(f"Completion failed: {e}")
            return []

@contextlib.contextmanager
def mute_stderr():
    """
    Context manager to temporarily suppress stderr.
    Used internally to prevent argparse error messages during completion.
    """

from argcomplete import mute_stderr

# Suppress error output during completion parsing
with mute_stderr():
    try:
        parser.parse_args(incomplete_args)
    except SystemExit:
        pass  # Expected during completion

safe_actions: Set[Type[argparse.Action]]

from argcomplete import safe_actions
import argparse

# Check if an action is safe to execute during completion
def is_safe_action(action):
    return action.__class__ in safe_actions

# Add custom safe actions
class MyCustomAction(argparse.Action):
    def __call__(self, parser, namespace, values, option_string=None):
        setattr(namespace, self.dest, values)

safe_actions.add(MyCustomAction)

def split_line(line: str, point: Optional[int] = None) -> Tuple[str, str, str, List[str], Optional[int]]:
    """
    Split command line respecting shell quoting and word boundaries.
    
    Parameters:
    - line: Command line string to split
    - point: Cursor position in the line (default: end of line)
    
    Returns:
    - Tuple containing:
        - cword_prequote: Quote character before current word
        - cword_prefix: Prefix of current word being completed
        - cword_suffix: Suffix of current word after cursor
        - comp_words: List of complete words before current position
        - last_wordbreak_pos: Position of last word break character
    """

from argcomplete import split_line

# Parse a command line
line = 'my-script --config "path with spaces" --output'
point = len(line)  # Cursor at end

prequote, prefix, suffix, words, wordbreak_pos = split_line(line, point)

print(f"Prequote: {repr(prequote)}")
print(f"Prefix: {repr(prefix)}")
print(f"Suffix: {repr(suffix)}")
print(f"Words: {words}")
print(f"Wordbreak position: {wordbreak_pos}")

import os

def is_completion_active():
    """Check if currently running in completion mode."""
    return "_ARGCOMPLETE" in os.environ

def is_debug_enabled():
    """Check if debug output is enabled."""
    return "_ARC_DEBUG" in os.environ

# Usage in custom code
if is_completion_active():
    # Special behavior during completion
    return get_completions_quickly()
else:
    # Normal execution
    return process_normally()

import os

def get_completion_shell():
    """Get the shell being used for completion."""
    return os.environ.get("_ARGCOMPLETE_SHELL", "unknown")

def is_zsh_completion():
    """Check if completion is running under zsh."""
    return get_completion_shell() == "zsh"

def is_bash_completion():
    """Check if completion is running under bash."""
    return get_completion_shell() == "bash"

# Usage
shell = get_completion_shell()
if shell == "zsh":
    # ZSH supports descriptions
    return {"option": "description"}
else:
    # Other shells
    return ["option"]

import os

def get_completion_line():
    """Get the full command line being completed."""
    return os.environ.get("COMP_LINE", "")

def get_completion_point():
    """Get cursor position in the command line."""
    return int(os.environ.get("COMP_POINT", 0))

def get_completion_type():
    """Get the type of completion being performed."""
    return os.environ.get("COMP_TYPE", "")

# Usage in advanced completers
class AdvancedCompleter(BaseCompleter):
    def __call__(self, prefix, **kwargs):
        comp_line = get_completion_line()
        comp_point = get_completion_point()
        
        # Analyze full command line for context
        if "--verbose" in comp_line:
            return self._get_verbose_completions(prefix)
        else:  
            return self._get_normal_completions(prefix)

from argcomplete import debug
import os

def debug_completion_state():
    """Output comprehensive debug information."""
    debug("=== Completion Debug Info ===")
    debug("COMP_LINE:", os.environ.get("COMP_LINE"))
    debug("COMP_POINT:", os.environ.get("COMP_POINT"))
    debug("Shell:", os.environ.get("_ARGCOMPLETE_SHELL"))
    debug("Args:", sys.argv)
    debug("===========================")

# Use at start of completion
if "_ARC_DEBUG" in os.environ:
    debug_completion_state()

from argcomplete import warn

def safe_completion_wrapper(func):
    """Decorator to safely handle completion errors."""
    def wrapper(*args, **kwargs):
        try:
            return func(*args, **kwargs)
        except Exception as e:
            warn(f"Completion error in {func.__name__}: {e}")
            return []
    return wrapper

# Use with custom completers
@safe_completion_wrapper
def my_completion_function(prefix):
    # Potentially error-prone completio logic
    return risky_completion_logic(prefix)

import time
from argcomplete import debug

def timed_completion(func):
    """Decorator to monitor completion performance."""
    def wrapper(*args, **kwargs):
        start_time = time.time()
        result = func(*args, **kwargs)
        elapsed = time.time() - start_time
        debug(f"Completion took {elapsed:.3f}s")
        return result
    return wrapper

# Monitor completion performance
@timed_completion
def slow_completer(prefix):
    # Completion logic that might be slow
    return expensive_completion_logic(prefix)