combine-diff: a few more finishing touches.

"new file" and "deleted file" were already reported in the
original code, but the logic was not as transparent as it could
have.  This uses a few variables and more comments to clarify
the flow.  The rule is: (1) if a path exists in the merge result
when no parent had it, we report "new" (otherwise it came from
the parents, as opposed to have added by the evil merge). (2) if
the path does not exist in the merge result, it is "deleted".

Since we can say "new" and "deleted", there is no reason not to
follow the /dev/null convention.  This fixes it.

Appending function name after @@@ ... @@@ is trivial, so
implement it.

Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 3 insertions, 3 deletions

diff --git a/Documentation/diff-format.txt b/Documentation/diff-format.txt
index 174d63a1e..ed4ebcbab 100644
--- a/Documentation/diff-format.txt
+++ b/Documentation/diff-format.txt
@@ -212,9 +212,9 @@ copying detection) are designed to work with diff of two
        --- a/file
        +++ b/file
 +
-Contrary to two-line header for traditional 'unified' diff
-format, and similar to filenames in ordinary "diff header",
-/dev/null is not used for creation or deletion.
+Similar to two-line header for traditional 'unified' diff
+format, `/dev/null` is used to signal created or deleted
+files.
 
 4.   Chunk header format is modified to prevent people from
      accidentally feeding it to `patch -p1`. Combined diff format