Re: git diff HEAD - only show modified files in completion

[Oliver Kiddle <opk@xxxxxxx>]

Ahmad Ismail wrote:
> I think I have to use:

> _git-diff 2>/dev/null
> functions[_git-diff-orig]=$functions[_git-diff]
>
> _git-diff() {
>     _git-diff-orig "$@"
>     ...
> }

It looks like you've removed the stack overflow question already so
I'm somewhat guessing at what your issue is. Mostly, you need to move
your own code up before calling _git-diff-orig. The tag-ordering styles
can only work when there is a single tag loop in which completions are
added.

In this case, it's probably easier to tweak the original _git-diff
function than to modify it from a wrapper. And using git diff HEAD or
git diff @ to get both staged and unstaged changes is a common enough
case to warrant being special-cased. So any thoughts on the following
patch for _git. Ideally it ought to be possible to correctly handle any
arbitrary base branch name but we have existing functions for taking
care of files modified relative to the HEAD.

Admittedly, __git_changed_files itself could be improved but that's a
separate issue.

Oliver

diff --git a/Completion/Unix/Command/_git b/Completion/Unix/Command/_git
index 05e2a2361..81a060e4d 100644
--- a/Completion/Unix/Command/_git
+++ b/Completion/Unix/Command/_git
@@ -806,11 +806,14 @@ _git-diff () {
             # Example: git diff branch1..branch2 <tab>
             __git_tree_files ${PREFIX:-.} $(__git_committish_range_last $line[1]) && ret=0
           elif __git_is_committish $line[1] || __git_is_treeish $line[1]; then
+            local files_alt='files::__git_tree_files ${PREFIX:-.} HEAD'
+            [[ $line[1] = (HEAD|@) ]] &&
+                files_alt='files::__git_changed_files'
             # Example: git diff branch1 <tab>
             _alternative \
               'commits::__git_commits' \
               'blobs-and-trees-in-treeish::__git_blobs_and_trees_in_treeish' \
-              'files::__git_tree_files ${PREFIX:-.} HEAD' && ret=0
+              $files_alt && ret=0
           elif __git_is_blob $line[1]; then
             _alternative \
               'files::__git_cached_files' \
@@ -831,6 +834,10 @@ _git-diff () {
               __git_is_treeish $line[2]; then
             # Example: git diff branch1 branch2 <tab>
             __git_tree_files ${PREFIX:-.} $line[2] && ret=0
+          elif [[ $line[1] = (HEAD|@) ]]; then
+            # Example: git diff @ file1 <tab>
+            # Example: git diff HEAD -- <tab>
+            __git_ignore_line __git_changed_files && ret=0
           elif __git_is_committish $line[1] || __git_is_treeish $line[1]; then
             # Example: git diff branch file1 <tab>
             # Example: git diff branch -- f<tab>