Complete paths of working trees and refs for 'git worktree's various
subcommands.

The last two patches do the actual improvements, the first four are
preparatory steps.

Changes since v1:

  - Added an in-code comment and clarified the commit message of patch
    5/6.

v1: https://public-inbox.org/git/20191017173501.3198-1-szeder.dev@gmail.com/T/#u

SZEDER Gábor (6):
  t9902-completion: add tests for the __git_find_on_cmdline() helper
  completion: clean up the __git_find_on_cmdline() helper function
  completion: return the index of found word from
    __git_find_on_cmdline()
  completion: simplify completing 'git worktree' subcommands and options
  completion: list existing working trees for 'git worktree' subcommands
  completion: list paths and refs for 'git worktree add'

 contrib/completion/git-completion.bash | 119 +++++++++++++++++++------
 t/t9902-completion.sh                  |  57 ++++++++++++
 2 files changed, 150 insertions(+), 26 deletions(-)

Range-diff against v1:
1:  bd68b0b64b = 1:  b370a97edc t9902-completion: add tests for the __git_find_on_cmdline() helper
2:  b5c0312db6 = 2:  fb8f1e4840 completion: clean up the __git_find_on_cmdline() helper function
3:  6999b0b8e2 = 3:  47aecb9ac0 completion: return the index of found word from __git_find_on_cmdline()
4:  dd38374f2f = 4:  00c5a0f7df completion: simplify completing 'git worktree' subcommands and options
5:  619ff7021c ! 5:  2e4b1b3931 completion: list existing working trees for 'git worktree' subcommands
    @@ Commit message
         Never list the path of the main working tree, as it cannot be moved,
         removed, locked, or unlocked.
     
    -    Arguably 'git worktree unlock <TAB>' should only complete locked
    -    working trees, but 'git worktree list --porcelain' doesn't indicate
    -    which working trees are locked.  So for now it will complete the paths
    -    of all existing working trees, including non-locked ones as well.
    +    Ideally we would only list unlocked working trees for the 'move',
    +    'remove', and 'lock' subcommands, and only locked ones for 'unlock'.
    +    Alas, 'git worktree list --porcelain' doesn't indicate which working
    +    trees are locked, so for now we'll complete the paths of all existing
    +    working trees.
     
         Signed-off-by: SZEDER Gábor [off-list ref]
     
    @@ contrib/completion/git-completion.bash: _git_whatchanged ()
     +{
     +	local IFS=$'\n'
     +	__gitcomp_nl "$(git worktree list --porcelain |
    ++		# Skip the first entry: it's the path of the main worktree,
    ++		# which can't be moved, removed, locked, etc.
     +		sed -n -e '2,$ s/^worktree //p')"
     +}
     +
6:  29a32e5d36 = 6:  16a9b5f4b2 completion: list paths and refs for 'git worktree add'
-- 
2.24.1.982.ga4d4aba446