Completions for some long options are missing. (doesn't parse --help output perfectly)

[Andrew]

I noticed today that "--recursive" is missing from the completions for grep. A quick glance grep's man page reveals that other long options such as "--text" are also missing. I'm not sure what the pattern is.

Steps to reproduce:

  1) Type "grep --".
  2) Press <Tab> twice.
  3) Observe that "--recursive" is missing.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: bash-completion 1:2.0-1ubuntu3
ProcVersionSignature: Ubuntu 3.8.0-17.27-generic 3.8.6
Uname: Linux 3.8.0-17-generic x86_64
NonfreeKernelModules: nvidia zfs zunicode zavl zcommon znvpair
ApportVersion: 2.9.2-0ubuntu5
Architecture: amd64
Date: Wed Apr 10 12:32:24 2013
InstallationDate: Installed on 2013-04-07 (2 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130402.1)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: bash-completion
UpgradeStatus: No upgrade log present (probably fresh install)

[Peter Cordes (peter-cordes)]

bash_completion uses
 sed -ne 's/.*\(--[-A-Za-z0-9]\{1,\}=\{0,1\}\).*/\1/p'
to parse the options out of the --help output for MANY commands, including grep.

Unfortunately, it trips up on lines like this from grep:
  -r, --recursive like --directories=recurse

because the .* matches right up to before --directories=recurse. d'oh.
It gets --directories out of that line.

[Peter Cordes (peter-cordes)]

fixed it:

echo ' -r, --recursive like --directories=recurse' | sed -ne 's/\([^-]\|-[^-]\)*\(--[-A-Za-z0-9]\{1,\}=\{0,1\}\).*/\2/p'
--recursive

using \([^-]\|-[^-]\)* instead of .* at the front of the pattern makes the greedy match at the front stop at the first --. If there are commands that use -- as formatting in their --help output, then this won't work, e.g.
 -r -- equivalent to --recursive
but otherwise this should be good. It's pretty much standard to list the actual options early in a line, rather than
  like --directories=recurse -r, --recursive

This goes in _longopt(), line 1801 of bash_completion.

I'll submit this upstream, too

[Peter Cordes (peter-cordes)]

upstream https://alioth.debian.org/tracker/index.php?func=detail&aid=314896&group_id=100114&atid=413095

Patch attached there. Also fixes
ls --directory --[TAB] => now completes options

  rather than deciding that it's right and user is wrong, and only accepting a directory name. Not smart for such a naive function.

[Mathew Hodson (mhodson)]

I don't know if the patch was accepted upstream, but this hasn't made it to Ubuntu.

Test cases in OP and comment #6 still fail on Zesty.