Merge branch 'tr/notes-display'

* tr/notes-display:
  git-notes(1): add a section about the meaning of history
  notes: track whether notes_trees were changed at all
  notes: add shorthand --ref to override GIT_NOTES_REF
  commit --amend: copy notes to the new commit
  rebase: support automatic notes copying
  notes: implement helpers needed for note copying during rewrite
  notes: implement 'git notes copy --stdin'
  rebase -i: invoke post-rewrite hook
  rebase: invoke post-rewrite hook
  commit --amend: invoke post-rewrite hook
  Documentation: document post-rewrite hook
  Support showing notes from more than one notes tree
  test-lib: unset GIT_NOTES_REF to stop it from influencing tests

Conflicts:
	git-am.sh
	refs.c

1 files changed, 38 insertions, 0 deletions

diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt
index 87e2c03..7183aa9 100644
--- a/Documentation/githooks.txt
+++ b/Documentation/githooks.txt
@@ -317,6 +317,44 @@ This hook is invoked by 'git gc --auto'. It takes no parameter, and
 exiting with non-zero status from this script causes the 'git gc --auto'
 to abort.
 
+post-rewrite
+~~~~~~~~~~~~
+
+This hook is invoked by commands that rewrite commits (`git commit
+--amend`, 'git-rebase'; currently 'git-filter-branch' does 'not' call
+it!).  Its first argument denotes the command it was invoked by:
+currently one of `amend` or `rebase`.  Further command-dependent
+arguments may be passed in the future.
+
+The hook receives a list of the rewritten commits on stdin, in the
+format
+
+  <old-sha1> SP <new-sha1> [ SP <extra-info> ] LF
+
+The 'extra-info' is again command-dependent.  If it is empty, the
+preceding SP is also omitted.  Currently, no commands pass any
+'extra-info'.
+
+The hook always runs after the automatic note copying (see
+"notes.rewrite.<command>" in linkgit:git-config.txt) has happened, and
+thus has access to these notes.
+
+The following command-specific comments apply:
+
+rebase::
+	For the 'squash' and 'fixup' operation, all commits that were
+	squashed are listed as being rewritten to the squashed commit.
+	This means that there will be several lines sharing the same
+	'new-sha1'.
++
+The commits are guaranteed to be listed in the order that they were
+processed by rebase.
+
+There is no default 'post-rewrite' hook, but see the
+`post-receive-copy-notes` script in `contrib/hooks` for an example
+that copies your git-notes to the rewritten commits.
+
+
 GIT
 ---
 Part of the linkgit:git[1] suite