completion: treat results of git ls-tree as file paths

Let's say there are files named 'foo bar.txt', and 'abc def/test.txt' in repository. When following commands trigger a completion: git show HEAD:fo<Tab> git show HEAD:ab<Tab> The completion results in bash/zsh: git show HEAD:foo bar.txt git show HEAD:abc def/ Where the both of them have an unescaped space in paths, so they'll be misread by git. All entries of git ls-tree either a filename or a directory, so __gitcomp_file() is proper rather than __gitcomp_nl(). Note the commit f12785a3, which handles quoted paths properly. Like this case, we should dequote $cur_ for ?*:* case. For example, let's say there is untracked directory 'abc deg', then trigger a completion: git show HEAD:abc\ de<Tab> git show HEAD:'abc de<Tab> git show HEAD:"abc de<Tab> should uniquely complete 'abc def', but bash completes 'abc def' and 'abc deg' instead. In zsh, triggering a completion: git show HEAD:abc\ def/<Tab> should complete 'test.txt', but nothing comes. The both problems will be resolved by dequoting paths. __git_complete_revlist_file() passes arguments to __gitcomp_nl() where the first one is a list something like: abc def/Z foo bar.txt Z where Z is the mark of the EOL. - The trailing space of blob in __git ls-tree | sed. It makes the completion results become: git show HEAD:foo\ bar.txt\ <CURSOR> So git will try to find a file named 'foo bar.txt ' instead. - The trailing slash of tree in __git ls-tree | sed. It makes the completion results on zsh become: git show HEAD:abc\ def/ <CURSOR> So that the last space on command like should be removed on zsh to complete filenames under 'abc def/'. Signed-off-by: Chayoung You <yousbe@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>