"""Pop up a reminder of how to call a function. Call Tips are floating windows which display function, class, and method parameter and docstring information when you type an opening parenthesis, and which disappear when you type a closing parenthesis. """ import __main__ import inspect import re import sys import textwrap import types from idlelib import calltip_w from idlelib.hyperparser import HyperParser class Calltip: def __init__(self, editwin=None): if editwin is None: # subprocess and test self.editwin = None else: self.editwin = editwin self.text = editwin.text self.active_calltip = None self._calltip_window = self._make_tk_calltip_window def close(self): self._calltip_window = None def _make_tk_calltip_window(self): # See __init__ for usage return calltip_w.CalltipWindow(self.text) def remove_calltip_window(self, event=None): if self.active_calltip: self.active_calltip.hidetip() self.active_calltip = None def force_open_calltip_event(self, event): "The user selected the menu entry or hotkey, open the tip." self.open_calltip(True) return "break" def try_open_calltip_event(self, event): """Happens when it would be nice to open a calltip, but not really necessary, for example after an opening bracket, so function calls won't be made. """ self.open_calltip(False) def refresh_calltip_event(self, event): if self.active_calltip and self.active_calltip.tipwindow: self.open_calltip(False) def open_calltip(self, evalfuncs): self.remove_calltip_window() hp = HyperParser(self.editwin, "insert") sur_paren = hp.get_surrounding_brackets('(') if not sur_paren: return hp.set_index(sur_paren[0]) expression = hp.get_expression() if not expression: return if not evalfuncs and (expression.find('(') != -1): return argspec = self.fetch_tip(expression) if not argspec: return self.active_calltip = self._calltip_window() self.active_calltip.showtip(argspec, sur_paren[0], sur_paren[1]) def fetch_tip(self, expression): """Return the argument list and docstring of a function or class. If there is a Python subprocess, get the calltip there. Otherwise, either this fetch_tip() is running in the subprocess or it was called in an IDLE running without the subprocess. The subprocess environment is that of the most recently run script. If two unrelated modules are being edited some calltips in the current module may be inoperative if the module was not the last to run. To find methods, fetch_tip must be fed a fully qualified name. """ try: rpcclt = self.editwin.flist.pyshell.interp.rpcclt except AttributeError: rpcclt = None if rpcclt: return rpcclt.remotecall("exec", "get_the_calltip", (expression,), {}) else: return get_argspec(get_entity(expression)) def get_entity(expression): """Return the object corresponding to expression evaluated in a namespace spanning sys.modules and __main.dict__. """ if expression: namespace = {**sys.modules, **__main__.__dict__} try: return eval(expression, namespace) # Only protect user code. except BaseException: # An uncaught exception closes idle, and eval can raise any # exception, especially if user classes are involved. return None # The following are used in get_argspec and some in tests _MAX_COLS = 85 _MAX_LINES = 5 # enough for bytes _INDENT = ' '*4 # for wrapped signatures _first_param = re.compile(r'(?<=\()\w*\,?\s*') _default_callable_argspec = "See source or doc" _invalid_method = "invalid method signature" _argument_positional = " # '/' marks preceding args as positional-only." def get_argspec(ob): '''Return a string describing the signature of a callable object, or ''. For Python-coded functions and methods, the first line is introspected. Delete 'self' parameter for classes (.__init__) and bound methods. The next lines are the first lines of the doc string up to the first empty line or _MAX_LINES. For builtins, this typically includes the arguments in addition to the return value. ''' # Determine function object fob to inspect. try: ob_call = ob.__call__ except BaseException: # Buggy user object could raise anything. return '' # No popup for non-callables. fob = ob_call if isinstance(ob_call, types.MethodType) else ob # Initialize argspec and wrap it to get lines. try: argspec = str(inspect.signature(fob)) except Exception as err: msg = str(err) if msg.startswith(_invalid_method): return _invalid_method else: argspec = '' if '/' in argspec and len(argspec) < _MAX_COLS - len(_argument_positional): # Add explanation TODO remove after 3.7, before 3.9. argspec += _argument_positional if isinstance(fob, type) and argspec == '()': # If fob has no argument, use default callable argspec. argspec = _default_callable_argspec lines = (textwrap.wrap(argspec, _MAX_COLS, subsequent_indent=_INDENT) if len(argspec) > _MAX_COLS else [argspec] if argspec else []) # Augment lines from docstring, if any, and join to get argspec. if isinstance(ob_call, types.MethodType): doc = ob_call.__doc__ else: doc = getattr(ob, "__doc__", "") if doc: for line in doc.split('\n', _MAX_LINES)[:_MAX_LINES]: line = line.strip() if not line: break if len(line) > _MAX_COLS: line = line[: _MAX_COLS - 3] + '...' lines.append(line) argspec = '\n'.join(lines) return argspec or _default_callable_argspec if __name__ == '__main__': from unittest import main main('idlelib.idle_test.test_calltip', verbosity=2)