Question

I need some help. I am completely stumped. I’m trying to write my own tab completion module for a custom shell style program (also completing arguments) I can tab complete the commands, but the arguments are giving me trouble. Can some one write a sample tab completing module for me to look at?
Available Commands:
[‘show’,’exit’,’clear’, ‘ship’]
for command show, first arg:
[‘ip’,’mac’,’options’]
and for sub arg IP:
[‘external,’internal’,’local’]

In the end I want to be able to go:

My Prompt > sh<tab>
show ship
My Prompt > sho<tab>
My Prompt > show <tab>
ip mac options
My Prompt > show ip <tab>
external local internal
My Prompt > show ip e<tab>
My Prompt > show ip external

and so on an so forth. If I just had one good working example I think I could figure this out. I’ve completely rewritten my tab completion code 5 times, but still I can’t get it. Could some one please help?

Answer 1

In the end I figured it out after the 7th rewrite. A little messier than I would like, but workable, likely I will clean this up later. Anyways, here’s the code:

"""defined earlier in the script:"""
COMMANDS=['show', 'exit', 'ship']
def complete(text, state, list = COMMANDS):
    for option in list:
        if option.startswith(text):
            if not state:
                return option
            else:
                state -= 1
def precomplete(text, state):
    BUFFER=readline.get_line_buffer()
    args=[None,None,None,None,None,None,None,None,None,None]
    argtemp=[]
    if BUFFER != "":
        i=-1
        while i != BUFFER.count(" "):
            if BUFFER.count(" ") >= 0:
                if BUFFER.count(" ") == 0: #1 because len() starts couting at 1
                    return complete(text, state)
                else:
                    print "Else triggered"
                    o=0
                    verb=[]
                    while complete(BUFFER.split()[0],o):
                        verb.append(complete(BUFFER.split()[0],o))
                        o=o+1
                    if len(verb) == 1:
                        verb=verb[0]
                        print verb
            if BUFFER.count(" ") >= 1:
                if  BUFFER.count(" ") == 1:
                    if verb == 'show':
                        return complete(text, state, ['mac', 'ip', 'arp'])
                else:
                    o=0
                    while complete(BUFFER[1],o,['mac', 'ip', 'arp']):
                        argtemp.append(complete(BUFFER[1],o,['mac', 'ip', 'arp']))
                        o=o+1
                    if len(argtemp) == 1:
                       argtemp==argtemp[0]
            i=i+1
    else:
        return complete(text,state)
readline.parse_and_bind("tab: complete")
readline.set_completer(precomplete)

EDIT: Full code:http://codepad.org/W3VHURUx