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-rw-r--r--Lib/idlelib/UndoDelegator.py352
1 files changed, 352 insertions, 0 deletions
diff --git a/Lib/idlelib/UndoDelegator.py b/Lib/idlelib/UndoDelegator.py
new file mode 100644
index 0000000..ec7af81
--- /dev/null
+++ b/Lib/idlelib/UndoDelegator.py
@@ -0,0 +1,352 @@
+import sys
+import string
+from Tkinter import *
+from Delegator import Delegator
+
+#$ event <<redo>>
+#$ win <Control-y>
+#$ unix <Alt-z>
+
+#$ event <<undo>>
+#$ win <Control-z>
+#$ unix <Control-z>
+
+#$ event <<dump-undo-state>>
+#$ win <Control-backslash>
+#$ unix <Control-backslash>
+
+
+class UndoDelegator(Delegator):
+
+ max_undo = 1000
+
+ def __init__(self):
+ Delegator.__init__(self)
+ self.reset_undo()
+
+ def setdelegate(self, delegate):
+ if self.delegate is not None:
+ self.unbind("<<undo>>")
+ self.unbind("<<redo>>")
+ self.unbind("<<dump-undo-state>>")
+ Delegator.setdelegate(self, delegate)
+ if delegate is not None:
+ self.bind("<<undo>>", self.undo_event)
+ self.bind("<<redo>>", self.redo_event)
+ self.bind("<<dump-undo-state>>", self.dump_event)
+
+ def dump_event(self, event):
+ from pprint import pprint
+ pprint(self.undolist[:self.pointer])
+ print "pointer:", self.pointer,
+ print "saved:", self.saved,
+ print "can_merge:", self.can_merge,
+ print "get_saved():", self.get_saved()
+ pprint(self.undolist[self.pointer:])
+ return "break"
+
+ def reset_undo(self):
+ self.was_saved = -1
+ self.pointer = 0
+ self.undolist = []
+ self.undoblock = 0 # or a CommandSequence instance
+ self.set_saved(1)
+
+ def set_saved(self, flag):
+ if flag:
+ self.saved = self.pointer
+ else:
+ self.saved = -1
+ self.can_merge = 0
+ self.check_saved()
+
+ def get_saved(self):
+ return self.saved == self.pointer
+
+ saved_change_hook = None
+
+ def set_saved_change_hook(self, hook):
+ self.saved_change_hook = hook
+
+ was_saved = -1
+
+ def check_saved(self):
+ is_saved = self.get_saved()
+ if is_saved != self.was_saved:
+ self.was_saved = is_saved
+ if self.saved_change_hook:
+ self.saved_change_hook()
+
+ def insert(self, index, chars, tags=None):
+ self.addcmd(InsertCommand(index, chars, tags))
+
+ def delete(self, index1, index2=None):
+ self.addcmd(DeleteCommand(index1, index2))
+
+ # Clients should call undo_block_start() and undo_block_stop()
+ # around a sequence of editing cmds to be treated as a unit by
+ # undo & redo. Nested matching calls are OK, and the inner calls
+ # then act like nops. OK too if no editing cmds, or only one
+ # editing cmd, is issued in between: if no cmds, the whole
+ # sequence has no effect; and if only one cmd, that cmd is entered
+ # directly into the undo list, as if undo_block_xxx hadn't been
+ # called. The intent of all that is to make this scheme easy
+ # to use: all the client has to worry about is making sure each
+ # _start() call is matched by a _stop() call.
+
+ def undo_block_start(self):
+ if self.undoblock == 0:
+ self.undoblock = CommandSequence()
+ self.undoblock.bump_depth()
+
+ def undo_block_stop(self):
+ if self.undoblock.bump_depth(-1) == 0:
+ cmd = self.undoblock
+ self.undoblock = 0
+ if len(cmd) > 0:
+ if len(cmd) == 1:
+ # no need to wrap a single cmd
+ cmd = cmd.getcmd(0)
+ # this blk of cmds, or single cmd, has already
+ # been done, so don't execute it again
+ self.addcmd(cmd, 0)
+
+ def addcmd(self, cmd, execute=1):
+ if execute:
+ cmd.do(self.delegate)
+ if self.undoblock != 0:
+ self.undoblock.append(cmd)
+ return
+ if self.can_merge and self.pointer > 0:
+ lastcmd = self.undolist[self.pointer-1]
+ if lastcmd.merge(cmd):
+ return
+ self.undolist[self.pointer:] = [cmd]
+ if self.saved > self.pointer:
+ self.saved = -1
+ self.pointer = self.pointer + 1
+ if len(self.undolist) > self.max_undo:
+ ##print "truncating undo list"
+ del self.undolist[0]
+ self.pointer = self.pointer - 1
+ if self.saved >= 0:
+ self.saved = self.saved - 1
+ self.can_merge = 1
+ self.check_saved()
+
+ def undo_event(self, event):
+ if self.pointer == 0:
+ self.bell()
+ return "break"
+ cmd = self.undolist[self.pointer - 1]
+ cmd.undo(self.delegate)
+ self.pointer = self.pointer - 1
+ self.can_merge = 0
+ self.check_saved()
+ return "break"
+
+ def redo_event(self, event):
+ if self.pointer >= len(self.undolist):
+ self.bell()
+ return "break"
+ cmd = self.undolist[self.pointer]
+ cmd.redo(self.delegate)
+ self.pointer = self.pointer + 1
+ self.can_merge = 0
+ self.check_saved()
+ return "break"
+
+
+class Command:
+
+ # Base class for Undoable commands
+
+ tags = None
+
+ def __init__(self, index1, index2, chars, tags=None):
+ self.marks_before = {}
+ self.marks_after = {}
+ self.index1 = index1
+ self.index2 = index2
+ self.chars = chars
+ if tags:
+ self.tags = tags
+
+ def __repr__(self):
+ s = self.__class__.__name__
+ t = (self.index1, self.index2, self.chars, self.tags)
+ if self.tags is None:
+ t = t[:-1]
+ return s + `t`
+
+ def do(self, text):
+ pass
+
+ def redo(self, text):
+ pass
+
+ def undo(self, text):
+ pass
+
+ def merge(self, cmd):
+ return 0
+
+ def save_marks(self, text):
+ marks = {}
+ for name in text.mark_names():
+ if name != "insert" and name != "current":
+ marks[name] = text.index(name)
+ return marks
+
+ def set_marks(self, text, marks):
+ for name, index in marks.items():
+ text.mark_set(name, index)
+
+
+class InsertCommand(Command):
+
+ # Undoable insert command
+
+ def __init__(self, index1, chars, tags=None):
+ Command.__init__(self, index1, None, chars, tags)
+
+ def do(self, text):
+ self.marks_before = self.save_marks(text)
+ self.index1 = text.index(self.index1)
+ if text.compare(self.index1, ">", "end-1c"):
+ # Insert before the final newline
+ self.index1 = text.index("end-1c")
+ text.insert(self.index1, self.chars, self.tags)
+ self.index2 = text.index("%s+%dc" % (self.index1, len(self.chars)))
+ self.marks_after = self.save_marks(text)
+ ##sys.__stderr__.write("do: %s\n" % self)
+
+ def redo(self, text):
+ text.mark_set('insert', self.index1)
+ text.insert(self.index1, self.chars, self.tags)
+ self.set_marks(text, self.marks_after)
+ text.see('insert')
+ ##sys.__stderr__.write("redo: %s\n" % self)
+
+ def undo(self, text):
+ text.mark_set('insert', self.index1)
+ text.delete(self.index1, self.index2)
+ self.set_marks(text, self.marks_before)
+ text.see('insert')
+ ##sys.__stderr__.write("undo: %s\n" % self)
+
+ def merge(self, cmd):
+ if self.__class__ is not cmd.__class__:
+ return 0
+ if self.index2 != cmd.index1:
+ return 0
+ if self.tags != cmd.tags:
+ return 0
+ if len(cmd.chars) != 1:
+ return 0
+ if self.chars and \
+ self.classify(self.chars[-1]) != self.classify(cmd.chars):
+ return 0
+ self.index2 = cmd.index2
+ self.chars = self.chars + cmd.chars
+ return 1
+
+ alphanumeric = string.letters + string.digits + "_"
+
+ def classify(self, c):
+ if c in self.alphanumeric:
+ return "alphanumeric"
+ if c == "\n":
+ return "newline"
+ return "punctuation"
+
+
+class DeleteCommand(Command):
+
+ # Undoable delete command
+
+ def __init__(self, index1, index2=None):
+ Command.__init__(self, index1, index2, None, None)
+
+ def do(self, text):
+ self.marks_before = self.save_marks(text)
+ self.index1 = text.index(self.index1)
+ if self.index2:
+ self.index2 = text.index(self.index2)
+ else:
+ self.index2 = text.index(self.index1 + " +1c")
+ if text.compare(self.index2, ">", "end-1c"):
+ # Don't delete the final newline
+ self.index2 = text.index("end-1c")
+ self.chars = text.get(self.index1, self.index2)
+ text.delete(self.index1, self.index2)
+ self.marks_after = self.save_marks(text)
+ ##sys.__stderr__.write("do: %s\n" % self)
+
+ def redo(self, text):
+ text.mark_set('insert', self.index1)
+ text.delete(self.index1, self.index2)
+ self.set_marks(text, self.marks_after)
+ text.see('insert')
+ ##sys.__stderr__.write("redo: %s\n" % self)
+
+ def undo(self, text):
+ text.mark_set('insert', self.index1)
+ text.insert(self.index1, self.chars)
+ self.set_marks(text, self.marks_before)
+ text.see('insert')
+ ##sys.__stderr__.write("undo: %s\n" % self)
+
+class CommandSequence(Command):
+
+ # Wrapper for a sequence of undoable cmds to be undone/redone
+ # as a unit
+
+ def __init__(self):
+ self.cmds = []
+ self.depth = 0
+
+ def __repr__(self):
+ s = self.__class__.__name__
+ strs = []
+ for cmd in self.cmds:
+ strs.append(" " + `cmd`)
+ return s + "(\n" + string.join(strs, ",\n") + "\n)"
+
+ def __len__(self):
+ return len(self.cmds)
+
+ def append(self, cmd):
+ self.cmds.append(cmd)
+
+ def getcmd(self, i):
+ return self.cmds[i]
+
+ def redo(self, text):
+ for cmd in self.cmds:
+ cmd.redo(text)
+
+ def undo(self, text):
+ cmds = self.cmds[:]
+ cmds.reverse()
+ for cmd in cmds:
+ cmd.undo(text)
+
+ def bump_depth(self, incr=1):
+ self.depth = self.depth + incr
+ return self.depth
+
+def main():
+ from Percolator import Percolator
+ root = Tk()
+ root.wm_protocol("WM_DELETE_WINDOW", root.quit)
+ text = Text()
+ text.pack()
+ text.focus_set()
+ p = Percolator(text)
+ d = UndoDelegator()
+ p.insertfilter(d)
+ root.mainloop()
+
+if __name__ == "__main__":
+ main()