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

diff --cc Documentation/config.txt
Simple merge

diff --cc Documentation/git-notes.txt
index bef2f3942e0540a4829a30f39c88d3414046d7d1,e2701cff1af034fbc1794f8e4b42458b67a47f92..4e5113b837230c8f050cf4bbe10e8de4b3271bd0
--- 1/Documentation/git-notes.txt
--- 2/Documentation/git-notes.txt
+++ b/Documentation/git-notes.txt
@@@ -52,9 -57,19 +57,19 @@@ add:
  copy::
        Copy the notes for the first object onto the second object.
        Abort if the second object already has notes, or if the first
 -      objects has none. (use -f to overwrite existing notes to the
 +      object has none (use -f to overwrite existing notes to the
        second object). This subcommand is equivalent to:
        `git notes add [-f] -C $(git notes list <from-object>) <to-object>`
+ +
+ In `\--stdin` mode, take lines in the format
+ +
+ ----------
+ <from-object> SP <to-object> [ SP <rest> ] LF
+ ----------
+ +
+ on standard input, and copy the notes from each <from-object> to its
+ corresponding <to-object>.  (The optional `<rest>` is ignored so that
+ the command can read the input given to the `post-rewrite` hook.)
  
  append::
        Append to the notes of an existing object (defaults to HEAD).

diff --cc builtin/commit.c
Simple merge

diff --cc builtin/log.c
Simple merge

diff --cc builtin/notes.c
index feb710ac4ada96339e42fe5838cf137e9ae4f12e,e5046b98ed1bd086457562fd21d494259c765f45..4543d113113f90d7fb262b5fe54cbe5f6dfe29fd
--- 1/builtin/notes.c
--- 2/builtin-notes.c
+++ b/builtin/notes.c
@@@ -278,25 -445,27 +436,32 @@@ int cmd_notes(int argc, const char **ar
        char logmsg[100];
  
        int list = 0, add = 0, copy = 0, append = 0, edit = 0, show = 0,
-           remove = 0, prune = 0, force = 0;
+           remove = 0, prune = 0, force = 0, from_stdin = 0;
        int given_object = 0, i = 1, retval = 0;
        struct msg_arg msg = { 0, 0, STRBUF_INIT };
+       const char *rewrite_cmd = NULL;
+       const char *override_notes_ref = NULL;
        struct option options[] = {
 -              OPT_GROUP("Notes options"),
 -              OPT_CALLBACK('m', "message", &msg, "MSG",
 -                           "note contents as a string", parse_msg_arg),
 -              OPT_CALLBACK('F', "file", &msg, "FILE",
 -                           "note contents in a file", parse_file_arg),
 -              OPT_CALLBACK('c', "reedit-message", &msg, "OBJECT",
 -                         "reuse and edit specified note object", parse_reedit_arg),
 -              OPT_CALLBACK('C', "reuse-message", &msg, "OBJECT",
 -                         "reuse specified note object", parse_reuse_arg),
 +              OPT_GROUP("Notes contents options"),
 +              { OPTION_CALLBACK, 'm', "message", &msg, "MSG",
 +                      "note contents as a string", PARSE_OPT_NONEG,
 +                      parse_msg_arg},
 +              { OPTION_CALLBACK, 'F', "file", &msg, "FILE",
 +                      "note contents in a file", PARSE_OPT_NONEG,
 +                      parse_file_arg},
 +              { OPTION_CALLBACK, 'c', "reedit-message", &msg, "OBJECT",
 +                      "reuse and edit specified note object", PARSE_OPT_NONEG,
 +                      parse_reedit_arg},
 +              { OPTION_CALLBACK, 'C', "reuse-message", &msg, "OBJECT",
 +                      "reuse specified note object", PARSE_OPT_NONEG,
 +                      parse_reuse_arg},
 +              OPT_GROUP("Other options"),
                OPT_BOOLEAN('f', "force", &force, "replace existing notes"),
+               OPT_BOOLEAN(0, "stdin", &from_stdin, "read objects from stdin"),
+               OPT_STRING(0, "ref", &override_notes_ref, "notes_ref",
+                          "use notes from <notes_ref>"),
+               OPT_STRING(0, "for-rewrite", &rewrite_cmd, "command",
+                          "load rewriting config for <command> (implies --stdin)"),
                OPT_END()
        };
  

diff --cc cache.h
index f62db0bd7e8f79f5d8a31e61c6164344bad10b65,a04f37f14be608bb9b8edb5580a4473e20a9d582..2928107bb135004e11f6a11a625067545680b62a
--- 1/cache.h
--- 2/cache.h
+++ b/cache.h
@@@ -387,16 -385,10 +387,19 @@@ static inline enum object_type object_t
  #define ATTRIBUTE_MACRO_PREFIX "[attr]"
  #define GIT_NOTES_REF_ENVIRONMENT "GIT_NOTES_REF"
  #define GIT_NOTES_DEFAULT_REF "refs/notes/commits"
+ #define GIT_NOTES_DISPLAY_REF_ENVIRONMENT "GIT_NOTES_DISPLAY_REF"
+ #define GIT_NOTES_REWRITE_REF_ENVIRONMENT "GIT_NOTES_REWRITE_REF"
+ #define GIT_NOTES_REWRITE_MODE_ENVIRONMENT "GIT_NOTES_REWRITE_MODE"
  
 +/*
 + * Repository-local GIT_* environment variables
 + * The array is NULL-terminated to simplify its usage in contexts such
 + * environment creation or simple walk of the list.
 + * The number of non-NULL entries is available as a macro.
 + */
 +#define LOCAL_REPO_ENV_SIZE 8
 +extern const char *const local_repo_env[LOCAL_REPO_ENV_SIZE + 1];
 +
  extern int is_bare_repository_cfg;
  extern int is_bare_repository(void);
  extern int is_inside_git_dir(void);

diff --cc git-am.sh
index 50a292a7da58aab3b5ce62347b02dee35395da2a,7644474bcabc191ef11ce6b885a62794ec730a9c..1056075545ad3e5e42626d167c91c1deada6186b
--- 1/git-am.sh
--- 2/git-am.sh
+++ b/git-am.sh
@@@ -791,5 -780,13 +797,12 @@@ d
        go_next
  done
  
 -git gc --auto
 -
+ if test -s "$dotest"/rewritten; then
+     git notes copy --for-rewrite=rebase < "$dotest"/rewritten
+     if test -x "$GIT_DIR"/hooks/post-rewrite; then
+       "$GIT_DIR"/hooks/post-rewrite rebase < "$dotest"/rewritten
+     fi
+ fi
+ 
  rm -fr "$dotest"
 +git gc --auto

diff --cc git-rebase--interactive.sh
Simple merge

diff --cc git-rebase.sh
Simple merge

diff --cc notes.c
index 07941b72352167fac9ce1b69f59cf377294a3c33,0261e7898a5ed6412f92a614818f75c53253b280..e425e198278bfb5c6a039dc88825568f1518e875
--- 1/notes.c
--- 2/notes.c
+++ b/notes.c
@@@ -891,9 -1028,10 +1028,10 @@@ void remove_note(struct notes_tree *t, 
        if (!t)
                t = &default_notes_tree;
        assert(t->initialized);
+       t->dirty = 1;
        hashcpy(l.key_sha1, object_sha1);
        hashclr(l.val_sha1);
 -      return note_tree_remove(t, t->root, 0, &l);
 +      note_tree_remove(t, t->root, 0, &l);
  }
  
  const unsigned char *get_note(struct notes_tree *t,

diff --cc refs.c
Simple merge

diff --cc revision.c
Simple merge

diff --cc revision.h
Simple merge

diff --cc t/t3301-notes.sh
Simple merge

diff --cc t/t3400-rebase.sh
Simple merge

diff --cc t/test-lib.sh
Simple merge