cpython/Lib/idlelib/calltips.py

176 lines
5.8 KiB
Python

"""calltips.py - An IDLE Extension to Jog Your Memory
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 inspect
import re
import sys
import textwrap
import types
from idlelib import calltip_w
from idlelib.hyperparser import HyperParser
import __main__
class CallTips:
menudefs = [
('edit', [
("Show call tip", "<<force-open-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.CallTip(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)
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.is_active():
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.copy()
namespace.update(__main__.__dict__)
try:
return eval(expression, namespace)
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"
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.
'''
argspec = ""
try:
ob_call = ob.__call__
except BaseException:
return argspec
if isinstance(ob, type):
fob = ob.__init__
elif isinstance(ob_call, types.MethodType):
fob = ob_call
else:
fob = ob
if isinstance(fob, (types.FunctionType, types.MethodType)):
argspec = inspect.formatargspec(*inspect.getfullargspec(fob))
if (isinstance(ob, (type, types.MethodType)) or
isinstance(ob_call, types.MethodType)):
argspec = _first_param.sub("", argspec)
lines = (textwrap.wrap(argspec, _MAX_COLS, subsequent_indent=_INDENT)
if len(argspec) > _MAX_COLS else [argspec] if argspec else [])
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)
if not argspec:
argspec = _default_callable_argspec
return argspec
if __name__ == '__main__':
from unittest import main
main('idlelib.idle_test.test_calltips', verbosity=2)