# System library imports
from IPython.external.qt import QtGui
# Local imports
from IPython.utils.traitlets import Bool
from console_widget import ConsoleWidget
class HistoryConsoleWidget(ConsoleWidget):
""" A ConsoleWidget that keeps a history of the commands that have been
executed and provides a readline-esque interface to this history.
"""
#------ Configuration ------------------------------------------------------
# If enabled, the input buffer will become "locked" to history movement when
# an edit is made to a multi-line input buffer. To override the lock, use
# Shift in conjunction with the standard history cycling keys.
history_lock = Bool(False, config=True)
#---------------------------------------------------------------------------
# 'object' interface
#---------------------------------------------------------------------------
def __init__(self, *args, **kw):
super(HistoryConsoleWidget, self).__init__(*args, **kw)
# HistoryConsoleWidget protected variables.
self._history = []
self._history_edits = {}
self._history_index = 0
self._history_prefix = ''
#---------------------------------------------------------------------------
# 'ConsoleWidget' public interface
#---------------------------------------------------------------------------
def execute(self, source=None, hidden=False, interactive=False):
""" Reimplemented to the store history.
"""
if not hidden:
history = self.input_buffer if source is None else source
executed = super(HistoryConsoleWidget, self).execute(
source, hidden, interactive)
if executed and not hidden:
# Save the command unless it was an empty string or was identical
# to the previous command.
history = history.rstrip()
if history and (not self._history or self._history[-1] != history):
self._history.append(history)
# Emulate readline: reset all history edits.
self._history_edits = {}
# Move the history index to the most recent item.
self._history_index = len(self._history)
return executed
#---------------------------------------------------------------------------
# 'ConsoleWidget' abstract interface
#---------------------------------------------------------------------------
def _up_pressed(self, shift_modifier):
""" Called when the up key is pressed. Returns whether to continue
processing the event.
"""
prompt_cursor = self._get_prompt_cursor()
if self._get_cursor().blockNumber() == prompt_cursor.blockNumber():
# Bail out if we're locked.
if self._history_locked() and not shift_modifier:
return False
# Set a search prefix based on the cursor position.
col = self._get_input_buffer_cursor_column()
input_buffer = self.input_buffer
if self._history_index == len(self._history) or \
(self._history_prefix and col != len(self._history_prefix)):
self._history_index = len(self._history)
self._history_prefix = input_buffer[:col]
# Perform the search.
self.history_previous(self._history_prefix,
as_prefix=not shift_modifier)
# Go to the first line of the prompt for seemless history scrolling.
# Emulate readline: keep the cursor position fixed for a prefix
# search.
cursor = self._get_prompt_cursor()
if self._history_prefix:
cursor.movePosition(QtGui.QTextCursor.Right,
n=len(self._history_prefix))
else:
cursor.movePosition(QtGui.QTextCursor.EndOfLine)
self._set_cursor(cursor)
return False
return True
def _down_pressed(self, shift_modifier):
""" Called when the down key is pressed. Returns whether to continue
processing the event.
"""
end_cursor = self._get_end_cursor()
if self._get_cursor().blockNumber() == end_cursor.blockNumber():
# Bail out if we're locked.
if self._history_locked() and not shift_modifier:
return False
# Perform the search.
replaced = self.history_next(self._history_prefix,
as_prefix=not shift_modifier)
# Emulate readline: keep the cursor position fixed for a prefix
# search. (We don't need to move the cursor to the end of the buffer
# in the other case because this happens automatically when the
# input buffer is set.)
if self._history_prefix and replaced:
cursor = self._get_prompt_cursor()
cursor.movePosition(QtGui.QTextCursor.Right,
n=len(self._history_prefix))
self._set_cursor(cursor)
return False
return True
#---------------------------------------------------------------------------
# 'HistoryConsoleWidget' public interface
#---------------------------------------------------------------------------
def history_previous(self, substring='', as_prefix=True):
""" If possible, set the input buffer to a previous history item.
Parameters:
-----------
substring : str, optional
If specified, search for an item with this substring.
as_prefix : bool, optional
If True, the substring must match at the beginning (default).
Returns:
--------
Whether the input buffer was changed.
"""
index = self._history_index
replace = False
while index > 0:
index -= 1
history = self._get_edited_history(index)
if (as_prefix and history.startswith(substring)) \
or (not as_prefix and substring in history):
replace = True
break
if replace:
self._store_edits()
self._history_index = index
self.input_buffer = history
return replace
def history_next(self, substring='', as_prefix=True):
""" If possible, set the input buffer to a subsequent history item.
Parameters:
-----------
substring : str, optional
If specified, search for an item with this substring.
as_prefix : bool, optional
If True, the substring must match at the beginning (default).
Returns:
--------
Whether the input buffer was changed.
"""
index = self._history_index
replace = False
while self._history_index < len(self._history):
index += 1
history = self._get_edited_history(index)
if (as_prefix and history.startswith(substring)) \
or (not as_prefix and substring in history):
replace = True
break
if replace:
self._store_edits()
self._history_index = index
self.input_buffer = history
return replace
def history_tail(self, n=10):
""" Get the local history list.
Parameters:
-----------
n : int
The (maximum) number of history items to get.
"""
return self._history[-n:]
#---------------------------------------------------------------------------
# 'HistoryConsoleWidget' protected interface
#---------------------------------------------------------------------------
def _history_locked(self):
""" Returns whether history movement is locked.
"""
return (self.history_lock and
(self._get_edited_history(self._history_index) !=
self.input_buffer) and
(self._get_prompt_cursor().blockNumber() !=
self._get_end_cursor().blockNumber()))
def _get_edited_history(self, index):
""" Retrieves a history item, possibly with temporary edits.
"""
if index in self._history_edits:
return self._history_edits[index]
elif index == len(self._history):
return unicode()
return self._history[index]
def _set_history(self, history):
""" Replace the current history with a sequence of history items.
"""
self._history = list(history)
self._history_edits = {}
self._history_index = len(self._history)
def _store_edits(self):
""" If there are edits to the current input buffer, store them.
"""
current = self.input_buffer
if self._history_index == len(self._history) or \
self._history[self._history_index] != current:
self._history_edits[self._history_index] = current