Add unbuffered_input context manager to Terminal

[ch3pjw]

I wanted to write a terminal app that didn't do local echoing of input and didn't wait until return was pressed before providing the input to stdin, so I added this context manager to my Terminal class. Hope it's of use!

[jquast]

:-)

Maybe you'd like https://gist.github.com/jquast/7018509 for the time being -- working towards getting it merged, one building block at a time.

[ch3pjw]

Gosh, that looks a whole bunch more comprehensive than mine! I never really know which bits of this terminal handling stuff will work between different terminals, yet alone across platform :-s

I can't see if it handles modifier keys yes? There's only one mention of ctrl... I fiddled a while back with making something that could handle combinations of keys like ctrl+pgup :-)

def escape_modifier(modifer_flags):
    shift = 'shift ' * (modifer_flags & 1)
    meta =  'meta ' * ((modifer_flags & 2) >> 1)
    ctrl = 'ctrl ' * ((modifer_flags & 4) >> 2)
    return ''.join([shift, meta, ctrl])


escape_sequence_to_name = {
    '[A': 'up',
    '[B': 'down',
    '[C': 'left',
    '[D': 'right',
    '[E': '5',
    '[F': 'end',
    '[G': '5',
    '[H': 'home',

    '[1~': 'home',
    '[2~': 'insert',
    '[3~': 'delete',
    '[4~': 'end',
    '[5~': 'page up',
    '[6~': 'page down',
    '[7~': 'home',
    '[8~': 'end',

    '[11~': 'f1', '[[A': 'f1',
    '[12~': 'f2', '[[B': 'f2',
    '[13~': 'f3', '[[C': 'f3',
    '[14~': 'f4', '[[D': 'f4',
    '[15~': 'f5', '[[E': 'f5',

    '[Z': 'shift tab'}


def _create_modified_movement_keys():
    modified_keys = {}
    for letter, key_name in zip(
            'ABCDEFGH',
             ('up', 'down', 'right', 'left', '5', 'end', '5', 'home')):
        for modifer_flags in range(1, 9):
            for prefix in ('[', '[1;'):
                sequence = prefix + str(modifer_flags) + letter
                modified_keys[sequence] = escape_modifier(modifer_flags) + key_name
    return modified_keys

escape_sequence_to_name.update(_create_modified_movement_keys())

[jquast]

This version I wrote does support some of them, as it does a sort of "reverse lookup" -- if curses knows to expect it, it works. (KEY_STAB for Shift+Tab, for instance). See when this demo first begins: http://asciinema.org/a/2859 all capability codes are printed on the screen.

There are raw capability codes in my fork like you've just presented. They're definitely not universal. I'm not sure if I'll leave it in, it was used as a "fall through" -- some terminal emulators lie, sending vt220 codes even though they reported 'xterm', etc.

[jquast]

Your request for a unbuffered_input context manager is being prepared for merge in the blessed-integration branch. It is called keystroke_input: https://github.com/erikrose/blessings/blob/blessed-integration/blessings/terminal.py#L592-630

As far as ctrl and meta keys, these are not yet supported. Created issue #98 for tracking if you'd like to continue the discussion there.