Había implementado Python Shell usando code.InteractiveConsole
para ejecutar los comandos para un proyecto. A continuación se muestra una versión simplificada, aunque todavía bastante larga porque había escrito enlaces para teclas especiales (como Retorno, Tabulador ...) para que se comporten como en la consola de Python. Es posible agregar más funciones como autocompletado con jedi y resaltado de sintaxis con pigmentos.
La idea principal es que utilizo el push()
método de code.InteractiveConsole
para ejecutar los comandos. Este método se devuelve True
si es un comando parcial, por ejemplo def test(x):
, y utilizo esta retroalimentación para insertar una ...
solicitud; de lo contrario, se muestra la salida y se muestra una nueva >>>
solicitud. Capturo la salida usandocontextlib.redirect_stdout
.
También hay mucho código que implica marcas e índices de comparación porque evito que el usuario inserte texto dentro de comandos ejecutados previamente. La idea es que creé una marca 'input' que me dice dónde está el inicio de la solicitud activa y self.compare('insert', '<', 'input')
puedo saber cuándo el usuario está tratando de insertar texto sobre la solicitud activa.
import tkinter as tk
import sys
import re
from code import InteractiveConsole
from contextlib import redirect_stderr, redirect_stdout
from io import StringIO
class History(list):
def __getitem__(self, index):
try:
return list.__getitem__(self, index)
except IndexError:
return
class TextConsole(tk.Text):
def __init__(self, master, **kw):
kw.setdefault('width', 50)
kw.setdefault('wrap', 'word')
kw.setdefault('prompt1', '>>> ')
kw.setdefault('prompt2', '... ')
banner = kw.pop('banner', 'Python %s\n' % sys.version)
self._prompt1 = kw.pop('prompt1')
self._prompt2 = kw.pop('prompt2')
tk.Text.__init__(self, master, **kw)
# --- history
self.history = History()
self._hist_item = 0
self._hist_match = ''
# --- initialization
self._console = InteractiveConsole() # python console to execute commands
self.insert('end', banner, 'banner')
self.prompt()
self.mark_set('input', 'insert')
self.mark_gravity('input', 'left')
# --- bindings
self.bind('<Control-Return>', self.on_ctrl_return)
self.bind('<Shift-Return>', self.on_shift_return)
self.bind('<KeyPress>', self.on_key_press)
self.bind('<KeyRelease>', self.on_key_release)
self.bind('<Tab>', self.on_tab)
self.bind('<Down>', self.on_down)
self.bind('<Up>', self.on_up)
self.bind('<Return>', self.on_return)
self.bind('<BackSpace>', self.on_backspace)
self.bind('<Control-c>', self.on_ctrl_c)
self.bind('<<Paste>>', self.on_paste)
def on_ctrl_c(self, event):
"""Copy selected code, removing prompts first"""
sel = self.tag_ranges('sel')
if sel:
txt = self.get('sel.first', 'sel.last').splitlines()
lines = []
for i, line in enumerate(txt):
if line.startswith(self._prompt1):
lines.append(line[len(self._prompt1):])
elif line.startswith(self._prompt2):
lines.append(line[len(self._prompt2):])
else:
lines.append(line)
self.clipboard_clear()
self.clipboard_append('\n'.join(lines))
return 'break'
def on_paste(self, event):
"""Paste commands"""
if self.compare('insert', '<', 'input'):
return "break"
sel = self.tag_ranges('sel')
if sel:
self.delete('sel.first', 'sel.last')
txt = self.clipboard_get()
self.insert("insert", txt)
self.insert_cmd(self.get("input", "end"))
return 'break'
def prompt(self, result=False):
"""Insert a prompt"""
if result:
self.insert('end', self._prompt2, 'prompt')
else:
self.insert('end', self._prompt1, 'prompt')
self.mark_set('input', 'end-1c')
def on_key_press(self, event):
"""Prevent text insertion in command history"""
if self.compare('insert', '<', 'input') and event.keysym not in ['Left', 'Right']:
self._hist_item = len(self.history)
self.mark_set('insert', 'input lineend')
if not event.char.isalnum():
return 'break'
def on_key_release(self, event):
"""Reset history scrolling"""
if self.compare('insert', '<', 'input') and event.keysym not in ['Left', 'Right']:
self._hist_item = len(self.history)
return 'break'
def on_up(self, event):
"""Handle up arrow key press"""
if self.compare('insert', '<', 'input'):
self.mark_set('insert', 'end')
return 'break'
elif self.index('input linestart') == self.index('insert linestart'):
# navigate history
line = self.get('input', 'insert')
self._hist_match = line
hist_item = self._hist_item
self._hist_item -= 1
item = self.history[self._hist_item]
while self._hist_item >= 0 and not item.startswith(line):
self._hist_item -= 1
item = self.history[self._hist_item]
if self._hist_item >= 0:
index = self.index('insert')
self.insert_cmd(item)
self.mark_set('insert', index)
else:
self._hist_item = hist_item
return 'break'
def on_down(self, event):
"""Handle down arrow key press"""
if self.compare('insert', '<', 'input'):
self.mark_set('insert', 'end')
return 'break'
elif self.compare('insert lineend', '==', 'end-1c'):
# navigate history
line = self._hist_match
self._hist_item += 1
item = self.history[self._hist_item]
while item is not None and not item.startswith(line):
self._hist_item += 1
item = self.history[self._hist_item]
if item is not None:
self.insert_cmd(item)
self.mark_set('insert', 'input+%ic' % len(self._hist_match))
else:
self._hist_item = len(self.history)
self.delete('input', 'end')
self.insert('insert', line)
return 'break'
def on_tab(self, event):
"""Handle tab key press"""
if self.compare('insert', '<', 'input'):
self.mark_set('insert', 'input lineend')
return "break"
# indent code
sel = self.tag_ranges('sel')
if sel:
start = str(self.index('sel.first'))
end = str(self.index('sel.last'))
start_line = int(start.split('.')[0])
end_line = int(end.split('.')[0]) + 1
for line in range(start_line, end_line):
self.insert('%i.0' % line, ' ')
else:
txt = self.get('insert-1c')
if not txt.isalnum() and txt != '.':
self.insert('insert', ' ')
return "break"
def on_shift_return(self, event):
"""Handle Shift+Return key press"""
if self.compare('insert', '<', 'input'):
self.mark_set('insert', 'input lineend')
return 'break'
else: # execute commands
self.mark_set('insert', 'end')
self.insert('insert', '\n')
self.insert('insert', self._prompt2, 'prompt')
self.eval_current(True)
def on_return(self, event=None):
"""Handle Return key press"""
if self.compare('insert', '<', 'input'):
self.mark_set('insert', 'input lineend')
return 'break'
else:
self.eval_current(True)
self.see('end')
return 'break'
def on_ctrl_return(self, event=None):
"""Handle Ctrl+Return key press"""
self.insert('insert', '\n' + self._prompt2, 'prompt')
return 'break'
def on_backspace(self, event):
"""Handle delete key press"""
if self.compare('insert', '<=', 'input'):
self.mark_set('insert', 'input lineend')
return 'break'
sel = self.tag_ranges('sel')
if sel:
self.delete('sel.first', 'sel.last')
else:
linestart = self.get('insert linestart', 'insert')
if re.search(r' $', linestart):
self.delete('insert-4c', 'insert')
else:
self.delete('insert-1c')
return 'break'
def insert_cmd(self, cmd):
"""Insert lines of code, adding prompts"""
input_index = self.index('input')
self.delete('input', 'end')
lines = cmd.splitlines()
if lines:
indent = len(re.search(r'^( )*', lines[0]).group())
self.insert('insert', lines[0][indent:])
for line in lines[1:]:
line = line[indent:]
self.insert('insert', '\n')
self.prompt(True)
self.insert('insert', line)
self.mark_set('input', input_index)
self.see('end')
def eval_current(self, auto_indent=False):
"""Evaluate code"""
index = self.index('input')
lines = self.get('input', 'insert lineend').splitlines() # commands to execute
self.mark_set('insert', 'insert lineend')
if lines: # there is code to execute
# remove prompts
lines = [lines[0].rstrip()] + [line[len(self._prompt2):].rstrip() for line in lines[1:]]
for i, l in enumerate(lines):
if l.endswith('?'):
lines[i] = 'help(%s)' % l[:-1]
cmds = '\n'.join(lines)
self.insert('insert', '\n')
out = StringIO() # command output
err = StringIO() # command error traceback
with redirect_stderr(err): # redirect error traceback to err
with redirect_stdout(out): # redirect command output
# execute commands in interactive console
res = self._console.push(cmds)
# if res is True, this is a partial command, e.g. 'def test():' and we need to wait for the rest of the code
errors = err.getvalue()
if errors: # there were errors during the execution
self.insert('end', errors) # display the traceback
self.mark_set('input', 'end')
self.see('end')
self.prompt() # insert new prompt
else:
output = out.getvalue() # get output
if output:
self.insert('end', output, 'output')
self.mark_set('input', 'end')
self.see('end')
if not res and self.compare('insert linestart', '>', 'insert'):
self.insert('insert', '\n')
self.prompt(res)
if auto_indent and lines:
# insert indentation similar to previous lines
indent = re.search(r'^( )*', lines[-1]).group()
line = lines[-1].strip()
if line and line[-1] == ':':
indent = indent + ' '
self.insert('insert', indent)
self.see('end')
if res:
self.mark_set('input', index)
self._console.resetbuffer() # clear buffer since the whole command will be retrieved from the text widget
elif lines:
self.history.append(lines) # add commands to history
self._hist_item = len(self.history)
out.close()
err.close()
else:
self.insert('insert', '\n')
self.prompt()
if __name__ == '__main__':
root = tk.Tk()
console = TextConsole(root)
console.pack(fill='both', expand=True)
root.mainloop()