Text History error when rolling back during transition

[aqua.soo]

I was trying out Text History from the old wiki's cookbook and noticed that the game encounters an error when you try to scroll back during a with transition, if the with statement is in its own line—as opposed to being a clause like show ... with.

The problem seems to be that a standalone with statement has no text to show. How could this be fixed?

Code: Select all

Full traceback:
  File "renpy/common/00gamemenu.rpy", line 163, in script
    $ ui.interact()
  File "/home/user/renpy/renpy/ast.py", line 756, in execute
    renpy.python.py_exec_bytecode(self.code.bytecode, self.hide, store=self.store)
  File "/home/user/renpy/renpy/python.py", line 1382, in py_exec_bytecode
    exec bytecode in globals, locals
  File "renpy/common/00gamemenu.rpy", line 163, in <module>
    $ ui.interact()
  File "/home/user/renpy/renpy/ui.py", line 264, in interact
    rv = renpy.game.interface.interact(roll_forward=roll_forward, **kwargs)
  File "/home/user/renpy/renpy/display/core.py", line 2058, in interact
    repeat, rv = self.interact_core(preloads=preloads, **kwargs)
  File "/home/user/renpy/renpy/display/core.py", line 2302, in interact_core
    root_widget.visit_all(lambda i : i.per_interact())
  File "/home/user/renpy/renpy/display/core.py", line 306, in visit_all
    d.visit_all(callback)
  File "/home/user/renpy/renpy/display/core.py", line 306, in visit_all
    d.visit_all(callback)
  File "/home/user/renpy/renpy/display/core.py", line 306, in visit_all
    d.visit_all(callback)
  File "/home/user/renpy/renpy/display/core.py", line 306, in visit_all
    d.visit_all(callback)
  File "/home/user/renpy/renpy/display/core.py", line 308, in visit_all
    callback(self)
  File "/home/user/renpy/renpy/display/core.py", line 2302, in <lambda>
    root_widget.visit_all(lambda i : i.per_interact())
  File "/home/user/renpy/renpy/display/screen.py", line 173, in per_interact
    self.update()
  File "/home/user/renpy/renpy/display/screen.py", line 277, in update
    self.screen.function(**self.scope)
  File "/home/user/renpy/renpy/screenlang.py", line 1236, in __call__
    renpy.python.py_exec_bytecode(self.code.bytecode, locals=scope)
  File "/home/user/renpy/renpy/python.py", line 1382, in py_exec_bytecode
    exec bytecode in globals, locals
  File "game/readback.rpy", line 296, in <module>
    text line[1]
  File "/home/user/renpy/renpy/ui.py", line 469, in __call__
    w = self.function(*args, **keyword)
  File "/home/user/renpy/renpy/text/text.py", line 1159, in __init__
    raise Exception("Cannot display {0!r} as text.".format(i))
Exception: Cannot display None as text.

While running game code:
  File "renpy/common/00gamemenu.rpy", line 163, in script
    $ ui.interact()
  File "renpy/common/00gamemenu.rpy", line 163, in <module>
    $ ui.interact()
  File "game/readback.rpy", line 296, in <module>
    text line[1]
Exception: Cannot display None as text.

[JD_Mortal]

Try empty quotes...

"" or '' <- Nothing between the quotes, not even a space. (Or try adding a space, if that might help.)

Thus, it will not be "nothing" (Null=Never-existed), but (Empty=No-longer-exists), thus, may display as a blank-line in the roll-back.

However, the rollback needs to be programmed to handle (Null), and (Empty), as neither of them can be displayed, and should not be "jumped to", when returning from a roll-back. Since a (Null) or an (Empty), should return to the "next line", where it may be a transition at the current (position), as in your case.

Thus, the WITH will now be bound to "something" as opposed to "nothing", even if that "something" is not "displayable".

[aqua.soo]

The issue indeed was that the text history log was picking up the None say attached to standalone with statements.

After fiddling around with the code, I found the problem. The if-elif-else block in screen text_history is supposed to prevent this kind of error, but it has a mistake. Here's the fix.

Code: Select all

    if not current_line[1] and len(readback_buffer) == 0:
        $ lines_to_show = []

    elif current_line[1] and len(readback_buffer) == 0:
        $ lines_to_show = [current_line]

    elif current_line[1] and not ( ( len(readback_buffer) == 3 and current_line == readback_buffer[-2]) or current_line == readback_buffer[-1]):  
        $ lines_to_show = readback_buffer + [current_line]

    else:
        $ lines_to_show = readback_buffer

The wiki says that its cookbook is outdated and people should check the forum's cookbook section. Should I fix the wiki's code or just post here?