Re: git add --patch newfile doesn't add newfile to cache ?

[Jeff King <peff@peff.net>]

On Mon, Oct 20, 2008 at 04:36:36PM +0200, Marc Weber wrote:

> Is this desired behaviour?
> [...]
>         git init
>         echo test > test
>         git add --patch test
>         echo "running status, nothing has been added"
>         git status

I think your example makes sense, but nobody ever really tried it
before. I use "git add -p" all the time, but almost always when I am
adding a new file, I add the whole contents.

I think there are two ways to go about fixing it:

  - in git-add--interactive.perl, the function patch_update_cmd
    explicitly looks at the list of modified files. It would have to
    also check for untracked files, which is easy. But we also need to
    keep track of which files are modified and which are untracked
    through the whole patching procedure, which is a bit more invasive.

  - the recently-added "git add -N" adds an empty file into the index,
    at which point we could add content in the normal way. So:

      git add -N test
      git add -p test

    should just work (but obviously requires two steps from the user).
    You could do something more automatic like the patch below, but I
    think the semantics aren't quite right. If you stage nothing for a
    newly added file, then you still end up with an empty version of the
    staged file in the index. I would expect the semantics to be:

      1. if you stage any content, then the file is added to the index
         with that content

      2. if you stage no content, then the file remains untracked

---
diff --git a/git-add--interactive.perl b/git-add--interactive.perl
index da768ee..72f8a67 100755
--- a/git-add--interactive.perl
+++ b/git-add--interactive.perl
@@ -811,6 +811,12 @@ EOF
 }
 
 sub patch_update_cmd {
+	my @new = list_untracked();
+	if (@new) {
+		system(qw(git add -N), @new)
+			and die "git add reported failure";
+	}
+
 	my @mods = grep { !($_->{BINARY}) } list_modified('file-only');
 	my @them;