fast-import: add support to delete refs

diff --git a/Documentation/git-fast-import.txt b/Documentation/git-fast-import.txt
index fd22a9a0c1312382a972a39e06063e7ff77b027d..c32a9a5aeed23357be8fcd5c69bd317f9de323ba 100644 (file)
--- a/Documentation/git-fast-import.txt
+++ b/Documentation/git-fast-import.txt
@@ -483,6 +483,9 @@ Marks must be declared (via `mark`) before they can be used.
 * Any valid Git SHA-1 expression that resolves to a commit.  See
   ``SPECIFYING REVISIONS'' in linkgit:gitrevisions[7] for details.
 
+* The special null SHA-1 (40 zeros) specifies that the branch is to be
+  removed.
+
 The special case of restarting an incremental import from the
 current branch value should be written as:
 ----