"Implement Idle Shell history mechanism with History class"

[0] Fix | Delete

[1] Fix | Delete

from idlelib.configHandler import idleConf

[2] Fix | Delete

[3] Fix | Delete

class History:

[4] Fix | Delete

''' Implement Idle Shell history mechanism.

[5] Fix | Delete

[6] Fix | Delete

store - Store source statement (called from PyShell.resetoutput).

[7] Fix | Delete

fetch - Fetch stored statement matching prefix already entered.

[8] Fix | Delete

history_next - Bound to <<history-next>> event (default Alt-N).

[9] Fix | Delete

history_prev - Bound to <<history-prev>> event (default Alt-P).

[10] Fix | Delete

'''

[11] Fix | Delete

def __init__(self, text):

[12] Fix | Delete

'''Initialize data attributes and bind event methods.

[13] Fix | Delete

[14] Fix | Delete

.text - Idle wrapper of tk Text widget, with .bell().

[15] Fix | Delete

.history - source statements, possibly with multiple lines.

[16] Fix | Delete

.prefix - source already entered at prompt; filters history list.

[17] Fix | Delete

.pointer - index into history.

[18] Fix | Delete

.cyclic - wrap around history list (or not).

[19] Fix | Delete

'''

[20] Fix | Delete

self.text = text

[21] Fix | Delete

self.history = []

[22] Fix | Delete

self.prefix = None

[23] Fix | Delete

self.pointer = None

[24] Fix | Delete

self.cyclic = idleConf.GetOption("main", "History", "cyclic", 1, "bool")

[25] Fix | Delete

text.bind("<<history-previous>>", self.history_prev)

[26] Fix | Delete

text.bind("<<history-next>>", self.history_next)

[27] Fix | Delete

[28] Fix | Delete

def history_next(self, event):

[29] Fix | Delete

"Fetch later statement; start with ealiest if cyclic."

[30] Fix | Delete

self.fetch(reverse=False)

[31] Fix | Delete

return "break"

[32] Fix | Delete

[33] Fix | Delete

def history_prev(self, event):

[34] Fix | Delete

"Fetch earlier statement; start with most recent."

[35] Fix | Delete

self.fetch(reverse=True)

[36] Fix | Delete

return "break"

[37] Fix | Delete

[38] Fix | Delete

def fetch(self, reverse):

[39] Fix | Delete

'''Fetch statememt and replace current line in text widget.

[40] Fix | Delete

[41] Fix | Delete

Set prefix and pointer as needed for successive fetches.

[42] Fix | Delete

Reset them to None, None when returning to the start line.

[43] Fix | Delete

Sound bell when return to start line or cannot leave a line

[44] Fix | Delete

because cyclic is False.

[45] Fix | Delete

'''

[46] Fix | Delete

nhist = len(self.history)

[47] Fix | Delete

pointer = self.pointer

[48] Fix | Delete

prefix = self.prefix

[49] Fix | Delete

if pointer is not None and prefix is not None:

[50] Fix | Delete

if self.text.compare("insert", "!=", "end-1c") or \

[51] Fix | Delete

self.text.get("iomark", "end-1c") != self.history[pointer]:

[52] Fix | Delete

pointer = prefix = None

[53] Fix | Delete

self.text.mark_set("insert", "end-1c") # != after cursor move

[54] Fix | Delete

if pointer is None or prefix is None:

[55] Fix | Delete

prefix = self.text.get("iomark", "end-1c")

[56] Fix | Delete

if reverse:

[57] Fix | Delete

pointer = nhist # will be decremented

[58] Fix | Delete

else:

[59] Fix | Delete

if self.cyclic:

[60] Fix | Delete

pointer = -1 # will be incremented

[61] Fix | Delete

else: # abort history_next

[62] Fix | Delete

self.text.bell()

[63] Fix | Delete

return

[64] Fix | Delete

nprefix = len(prefix)

[65] Fix | Delete

while 1:

[66] Fix | Delete

pointer += -1 if reverse else 1

[67] Fix | Delete

if pointer < 0 or pointer >= nhist:

[68] Fix | Delete

self.text.bell()

[69] Fix | Delete

if not self.cyclic and pointer < 0: # abort history_prev

[70] Fix | Delete

return

[71] Fix | Delete

else:

[72] Fix | Delete

if self.text.get("iomark", "end-1c") != prefix:

[73] Fix | Delete

self.text.delete("iomark", "end-1c")

[74] Fix | Delete

self.text.insert("iomark", prefix)

[75] Fix | Delete

pointer = prefix = None

[76] Fix | Delete

break

[77] Fix | Delete

item = self.history[pointer]

[78] Fix | Delete

if item[:nprefix] == prefix and len(item) > nprefix:

[79] Fix | Delete

self.text.delete("iomark", "end-1c")

[80] Fix | Delete

self.text.insert("iomark", item)

[81] Fix | Delete

break

[82] Fix | Delete

self.text.see("insert")

[83] Fix | Delete

self.text.tag_remove("sel", "1.0", "end")

[84] Fix | Delete

self.pointer = pointer

[85] Fix | Delete

self.prefix = prefix

[86] Fix | Delete

[87] Fix | Delete

def store(self, source):

[88] Fix | Delete

"Store Shell input statement into history list."

[89] Fix | Delete

source = source.strip()

[90] Fix | Delete

if len(source) > 2:

[91] Fix | Delete

# avoid duplicates

[92] Fix | Delete

try:

[93] Fix | Delete

self.history.remove(source)

[94] Fix | Delete

except ValueError:

[95] Fix | Delete

pass

[96] Fix | Delete

self.history.append(source)

[97] Fix | Delete

self.pointer = None

[98] Fix | Delete

self.prefix = None

[99] Fix | Delete

[100] Fix | Delete

if __name__ == "__main__":

[101] Fix | Delete

from unittest import main

[102] Fix | Delete

main('idlelib.idle_test.test_idlehistory', verbosity=2, exit=False)

[103] Fix | Delete

[104] Fix | Delete