from pyqtgraph.Qt import QtCore, QtGui
import sys, re, os, time, traceback, subprocess
import pyqtgraph as pg
from . import template
import pyqtgraph.exceptionHandling as exceptionHandling
import pickle
class ConsoleWidget(QtGui.QWidget):
"""
Widget displaying console output and accepting command input.
Implements:
- eval python expressions / exec python statements
- storable history of commands
- exception handling allowing commands to be interpreted in the context of any level in the exception stack frame
Why not just use python in an interactive shell (or ipython) ? There are a few reasons:
- pyside does not yet allow Qt event processing and interactive shell at the same time
- on some systems, typing in the console _blocks_ the qt event loop until the user presses enter. This can
be baffling and frustrating to users since it would appear the program has frozen.
- some terminals (eg windows cmd.exe) have notoriously unfriendly interfaces
- ability to add extra features like exception stack introspection
- ability to have multiple interactive prompts, including for spawned sub-processes
"""
def __init__(self, parent=None, namespace=None, historyFile=None, text=None, editor=None):
"""
============ ============================================================================
Arguments:
namespace dictionary containing the initial variables present in the default namespace
historyFile optional file for storing command history
text initial text to display in the console window
editor optional string for invoking code editor (called when stack trace entries are
double-clicked). May contain {fileName} and {lineNum} format keys. Example::
editorCommand --loadfile {fileName} --gotoline {lineNum}
============ =============================================================================
"""
QtGui.QWidget.__init__(self, parent)
if namespace is None:
namespace = {}
self.localNamespace = namespace
self.editor = editor
self.multiline = None
self.inCmd = False
self.ui = template.Ui_Form()
self.ui.setupUi(self)
self.output = self.ui.output
self.input = self.ui.input
self.input.setFocus()
if text is not None:
self.output.setPlainText(text)
self.historyFile = historyFile
history = self.loadHistory()
if history is not None:
self.input.history = [""] + history
self.ui.historyList.addItems(history[::-1])
self.ui.historyList.hide()
self.ui.exceptionGroup.hide()
self.input.sigExecuteCmd.connect(self.runCmd)
self.ui.historyBtn.toggled.connect(self.ui.historyList.setVisible)
self.ui.historyList.itemClicked.connect(self.cmdSelected)
self.ui.historyList.itemDoubleClicked.connect(self.cmdDblClicked)
self.ui.exceptionBtn.toggled.connect(self.ui.exceptionGroup.setVisible)
self.ui.catchAllExceptionsBtn.toggled.connect(self.catchAllExceptions)
self.ui.catchNextExceptionBtn.toggled.connect(self.catchNextException)
self.ui.clearExceptionBtn.clicked.connect(self.clearExceptionClicked)
self.ui.exceptionStackList.itemClicked.connect(self.stackItemClicked)
self.ui.exceptionStackList.itemDoubleClicked.connect(self.stackItemDblClicked)
self.ui.onlyUncaughtCheck.toggled.connect(self.updateSysTrace)
self.currentTraceback = None
def loadHistory(self):
"""Return the list of previously-invoked command strings (or None)."""
if self.historyFile is not None:
return pickle.load(open(self.historyFile, 'rb'))
def saveHistory(self, history):
"""Store the list of previously-invoked command strings."""
if self.historyFile is not None:
pickle.dump(open(self.historyFile, 'wb'), history)
def runCmd(self, cmd):
#cmd = str(self.input.lastCmd)
self.stdout = sys.stdout
self.stderr = sys.stderr
encCmd = re.sub(r'>', '>', re.sub(r'<', '<', cmd))
encCmd = re.sub(r' ', ' ', encCmd)
self.ui.historyList.addItem(cmd)
self.saveHistory(self.input.history[1:100])
try:
sys.stdout = self
sys.stderr = self
if self.multiline is not None:
self.write("
%s\n"%encCmd, html=True)
self.execMulti(cmd)
else:
self.write("
%s\n"%encCmd, html=True)
self.inCmd = True
self.execSingle(cmd)
if not self.inCmd:
self.write("
\n", html=True)
finally:
sys.stdout = self.stdout
sys.stderr = self.stderr
sb = self.output.verticalScrollBar()
sb.setValue(sb.maximum())
sb = self.ui.historyList.verticalScrollBar()
sb.setValue(sb.maximum())
def globals(self):
frame = self.currentFrame()
if frame is not None and self.ui.runSelectedFrameCheck.isChecked():
return self.currentFrame().tb_frame.f_globals
else:
return globals()
def locals(self):
frame = self.currentFrame()
if frame is not None and self.ui.runSelectedFrameCheck.isChecked():
return self.currentFrame().tb_frame.f_locals
else:
return self.localNamespace
def currentFrame(self):
## Return the currently selected exception stack frame (or None if there is no exception)
if self.currentTraceback is None:
return None
index = self.ui.exceptionStackList.currentRow()
tb = self.currentTraceback
for i in range(index):
tb = tb.tb_next
return tb
def execSingle(self, cmd):
try:
output = eval(cmd, self.globals(), self.locals())
self.write(repr(output) + '\n')
except SyntaxError:
try:
exec(cmd, self.globals(), self.locals())
except SyntaxError as exc:
if 'unexpected EOF' in exc.msg:
self.multiline = cmd
else:
self.displayException()
except:
self.displayException()
except:
self.displayException()
def execMulti(self, nextLine):
self.stdout.write(nextLine+"\n")
if nextLine.strip() != '':
self.multiline += "\n" + nextLine
return
else:
cmd = self.multiline
try:
output = eval(cmd, self.globals(), self.locals())
self.write(str(output) + '\n')
self.multiline = None
except SyntaxError:
try:
exec(cmd, self.globals(), self.locals())
self.multiline = None
except SyntaxError as exc:
if 'unexpected EOF' in exc.msg:
self.multiline = cmd
else:
self.displayException()
self.multiline = None
except:
self.displayException()
self.multiline = None
except:
self.displayException()
self.multiline = None
def write(self, strn, html=False):
self.output.moveCursor(QtGui.QTextCursor.End)
if html:
self.output.textCursor().insertHtml(strn)
else:
if self.inCmd:
self.inCmd = False
self.output.textCursor().insertHtml("
")
#self.stdout.write("
")
self.output.insertPlainText(strn)
#self.stdout.write(strn)
def displayException(self):
tb = traceback.format_exc()
lines = []
indent = 4
prefix = ''
for l in tb.split('\n'):
lines.append(" "*indent + prefix + l)
self.write('\n'.join(lines))
def cmdSelected(self, item):
index = -(self.ui.historyList.row(item)+1)
self.input.setHistory(index)
self.input.setFocus()
def cmdDblClicked(self, item):
index = -(self.ui.historyList.row(item)+1)
self.input.setHistory(index)
self.input.execCmd()
def flush(self):
pass
def catchAllExceptions(self, catch=True):
"""
If True, the console will catch all unhandled exceptions and display the stack
trace. Each exception caught clears the last.
"""
self.ui.catchAllExceptionsBtn.setChecked(catch)
if catch:
self.ui.catchNextExceptionBtn.setChecked(False)
self.enableExceptionHandling()
self.ui.exceptionBtn.setChecked(True)
else:
self.disableExceptionHandling()
def catchNextException(self, catch=True):
"""
If True, the console will catch the next unhandled exception and display the stack
trace.
"""
self.ui.catchNextExceptionBtn.setChecked(catch)
if catch:
self.ui.catchAllExceptionsBtn.setChecked(False)
self.enableExceptionHandling()
self.ui.exceptionBtn.setChecked(True)
else:
self.disableExceptionHandling()
def enableExceptionHandling(self):
exceptionHandling.register(self.exceptionHandler)
self.updateSysTrace()
def disableExceptionHandling(self):
exceptionHandling.unregister(self.exceptionHandler)
self.updateSysTrace()
def clearExceptionClicked(self):
self.currentTraceback = None
self.ui.exceptionInfoLabel.setText("[No current exception]")
self.ui.exceptionStackList.clear()
self.ui.clearExceptionBtn.setEnabled(False)
def stackItemClicked(self, item):
pass
def stackItemDblClicked(self, item):
editor = self.editor
if editor is None:
editor = pg.getConfigOption('editorCommand')
if editor is None:
return
tb = self.currentFrame()
lineNum = tb.tb_lineno
fileName = tb.tb_frame.f_code.co_filename
subprocess.Popen(self.editor.format(fileName=fileName, lineNum=lineNum), shell=True)
#def allExceptionsHandler(self, *args):
#self.exceptionHandler(*args)
#def nextExceptionHandler(self, *args):
#self.ui.catchNextExceptionBtn.setChecked(False)
#self.exceptionHandler(*args)
def updateSysTrace(self):
## Install or uninstall sys.settrace handler
if not self.ui.catchNextExceptionBtn.isChecked() and not self.ui.catchAllExceptionsBtn.isChecked():
if sys.gettrace() == self.systrace:
sys.settrace(None)
return
if self.ui.onlyUncaughtCheck.isChecked():
if sys.gettrace() == self.systrace:
sys.settrace(None)
else:
if sys.gettrace() is not None and sys.gettrace() != self.systrace:
self.ui.onlyUncaughtCheck.setChecked(False)
raise Exception("sys.settrace is in use; cannot monitor for caught exceptions.")
else:
sys.settrace(self.systrace)
def exceptionHandler(self, excType, exc, tb):
if self.ui.catchNextExceptionBtn.isChecked():
self.ui.catchNextExceptionBtn.setChecked(False)
self.ui.clearExceptionBtn.setEnabled(True)
self.currentTraceback = tb
excMessage = ''.join(traceback.format_exception_only(excType, exc))
self.ui.exceptionInfoLabel.setText(excMessage)
self.ui.exceptionStackList.clear()
for index, line in enumerate(traceback.extract_tb(tb)):
self.ui.exceptionStackList.addItem('File "%s", line %s, in %s()\n %s' % line)
def systrace(self, frame, event, arg):
if event == 'exception':
self.exceptionHandler(*arg)
return self.systrace