[PATCH 2/2] bash: complete 'git diff ...branc<TAB>'

While doing a final sanity check before merging a topic Bsomething, it is a good idea to review what damage Bsomething branch would make, by running:

    $ git diff ...Bsomething

Unfortunately, our completion script for 'git diff' doesn't offer anything after '...'. This is because 'git diff's completion function invokes __git_complete_file() for non-option arguments to complete the '<tree>:<path>' extended SHA-1 notation, but this helper function doesn't support refs after '...' or '..'. Completion of refs after '...' or '..' is supported by the __git_complete_revlist() helper function, but that doesn't support '<tree>:<path>'.

To support both '...<ref>' and '<tree>:<path>' notations for 'git diff', this patch, instead of adding yet another helper function, joins __git_complete_file() and __git_complete_revlist() into the new common function __git_complete_revlist_file(). The old helper functions __git_complete_file() and __git_complete_revlist() are changed to be a direct wrapper around the new __git_complete_revlist_file(), because they might be used in user-supplied completion scripts and we don't want to break them.

This change will cause some wrong suggestions for other commands which use __git_complete_file() ('git diff' and friends) or __git_complete_revlist() ('git log' and friends), e.g. 'git diff ...master:Doc<TAB>' and 'git log master:Doc<TAB>' will complete the path to 'Documentation/', although neither commands make any sense. However, both of these were actively wrong to begin with as soon as the user entered the ':', so there is no real harm done.

Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: SZEDER Gábor <szeder@ira.uka.de>
---
 contrib/completion/git-completion.bash |   29 ++++++++++++++++-------------
 1 files changed, 16 insertions(+), 13 deletions(-)