Don't use extglob in bash/docker-machine.bash

[Empact]

extglob is not needed here - the only call is:
_docker_machine_map_key_of_current_option '--filter'

So $glob is always '--filter', so there isn't every a pattern-list to match.

According to my testing completion for docker-machine
ls --filter completion works for both driver and state

Fixes #4126
Introduced in fd9a0a6

[GordonTheTurtle]

Please sign your commits following these rules:
https://github.com/moby/moby/blob/master/CONTRIBUTING.md#sign-your-work
The easiest way to do this is to amend the last commit:

$ git clone -b "extglob" git@github.com:Empact/machine.git somewhere
$ cd somewhere
$ git commit --amend -s --no-edit
$ git push -f

Amending updates the existing PR. You DO NOT need to open a new one.

[Empact]

cc @albers

[albers]

Thanks for the ping. I'll take a look at it.

[albers]

Ah, Mac OS again with its ancient bash.
This function was taken from Docker's bash completion which takes care of temporarily setting the extglob option while loading the script. I forgot to take this into account here.

@Empact You're right: no extglob is needed here, so it's probably best to keep the code simple. Thanks very much for fixing this.

To verify without a Mac:
Original code fails to load with bash 3.2.57:

$ docker run --rm --volume $(pwd)/contrib/completion/bash/docker-machine.bash:/docker-completion albers/bash-completion-mac bash -c ". /docker-completion" && echo OK
/docker-completion: line 86: syntax error in conditional expression: unexpected token `('
/docker-completion: line 86: syntax error near `@($'
/docker-completion: line 86: `    [[ ${words[$glob_pos]} == @($glob) ]] && echo "$key"'

With the fix it loads properly:

$ docker run --rm --volume $(pwd)/contrib/completion/bash/docker-machine.bash:/docker-completion albers/bash-completion-mac bash -c ". /docker-completion" && echo OK
OK

LGTM

@shin- This is a bugfix and should go into 1.12.0.

[jakirkham]

Would it be reasonable to test against bash 3.2.57 to catch errors like this during development?

[albers]

@jakirkham I'm working on this. Similar to docker/cli#266, a test like docker run --rm --volume $(pwd)/contrib/completion/bash/docker-machine.bash:/docker-completion albers/bash-completion-mac bash -c ". /docker-completion" should be added.
I'm not familiar with the build tooling, though, so this will take some time.

[shin-]

Thank you both!