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

Documentation/config.txt

@@ -519,10 +519,12 @@ check that makes sure that existing object files will not get overwritten.
 core.notesRef::
 	When showing commit messages, also show notes which are stored in
 	the given ref.  This ref is expected to contain files named
-	after the full SHA-1 of the commit they annotate.
+	after the full SHA-1 of the commit they annotate.  The ref
+	must be fully qualified.
 +
 If such a file exists in the given ref, the referenced blob is read, and
-appended to the commit message, separated by a "Notes:" line.  If the
+appended to the commit message, separated by a "Notes (<refname>):"
+line (shortened to "Notes:" in the case of "refs/notes/commits").  If the
 given ref itself does not exist, it is not an error, but means that no
 notes should be printed.
 +
@@ -1334,6 +1336,53 @@ mergetool.keepTemporaries::
 mergetool.prompt::
 	Prompt before each invocation of the merge resolution program.
 
+notes.displayRef::
+	The (fully qualified) refname from which to show notes when
+	showing commit messages.  The value of this variable can be set
+	to a glob, in which case notes from all matching refs will be
+	shown.  You may also specify this configuration variable
+	several times.  A warning will be issued for refs that do not
+	exist, but a glob that does not match any refs is silently
+	ignored.
++
+This setting can be overridden with the `GIT_NOTES_DISPLAY_REF`
+environment variable, which must be a colon separated list of refs or
+globs.
++
+The effective value of "core.notesRef" (possibly overridden by
+GIT_NOTES_REF) is also implicitly added to the list of refs to be
+displayed.
+
+notes.rewrite.<command>::
+	When rewriting commits with <command> (currently `amend` or
+	`rebase`) and this variable is set to `true`, git
+	automatically copies your notes from the original to the
+	rewritten commit.  Defaults to `true`, but see
+	"notes.rewriteRef" below.
++
+This setting can be overridden with the `GIT_NOTES_REWRITE_REF`
+environment variable, which must be a colon separated list of refs or
+globs.
+
+notes.rewriteMode::
+	When copying notes during a rewrite (see the
+	"notes.rewrite.<command>" option), determines what to do if
+	the target commit already has a note.  Must be one of
+	`overwrite`, `concatenate`, or `ignore`.  Defaults to
+	`concatenate`.
++
+This setting can be overridden with the `GIT_NOTES_REWRITE_MODE`
+environment variable.
+
+notes.rewriteRef::
+	When copying notes during a rewrite, specifies the (fully
+	qualified) ref whose notes should be copied.  The ref may be a
+	glob, in which case notes in all matching refs will be copied.
+	You may also specify this configuration several times.
++
+Does not have a default value; you must configure this variable to
+enable note rewriting.
+
 pack.window::
 	The size of the window used by linkgit:git-pack-objects[1] when no
 	window size is given on the command line. Defaults to 10.

Documentation/git-notes.txt

@@ -10,7 +10,7 @@ SYNOPSIS
 [verse]
 'git notes' [list [<object>]]
 'git notes' add [-f] [-F <file> | -m <msg> | (-c | -C) <object>] [<object>]
-'git notes' copy [-f] <from-object> <to-object>
+'git notes' copy [-f] ( --stdin | <from-object> <to-object> )
 'git notes' append [-F <file> | -m <msg> | (-c | -C) <object>] [<object>]
 'git notes' edit [<object>]
 'git notes' show [<object>]
@@ -27,12 +27,17 @@ A typical use of notes is to extend a commit message without having
 to change the commit itself. Such commit notes can be shown by `git log`
 along with the original commit message. To discern these notes from the
 message stored in the commit object, the notes are indented like the
-message, after an unindented line saying "Notes:".
+message, after an unindented line saying "Notes (<refname>):" (or
+"Notes:" for the default setting).
 
-To disable notes, you have to set the config variable core.notesRef to
-the empty string.  Alternatively, you can set it to a different ref,
-something like "refs/notes/bugzilla".  This setting can be overridden
-by the environment variable "GIT_NOTES_REF".
+This command always manipulates the notes specified in "core.notesRef"
+(see linkgit:git-config[1]), which can be overridden by GIT_NOTES_REF.
+To change which notes are shown by 'git-log', see the
+"notes.displayRef" configuration.
+
+See the description of "notes.rewrite.<command>" in
+linkgit:git-config[1] for a way of carrying your notes across commands
+that rewrite commits.
 
 
 SUBCOMMANDS
@@ -55,6 +60,16 @@ copy::
 	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).
@@ -101,6 +116,25 @@ OPTIONS
 	Like '-C', but with '-c' the editor is invoked, so that
 	the user can further edit the note message.
 
+--ref <ref>::
+	Manipulate the notes tree in <ref>.  This overrides both
+	GIT_NOTES_REF and the "core.notesRef" configuration.  The ref
+	is taken to be in `refs/notes/` if it is not qualified.
+
+
+NOTES
+-----
+
+Every notes change creates a new commit at the specified notes ref.
+You can therefore inspect the history of the notes by invoking, e.g.,
+`git log -p notes/commits`.
+
+Currently the commit message only records which operation triggered
+the update, and the commit authorship is determined according to the
+usual rules (see linkgit:git-commit[1]).  These details may change in
+the future.
+
+
 Author
 ------
 Written by Johannes Schindelin <johannes.schindelin@gmx.de> and

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

Documentation/pretty-options.txt

@@ -30,9 +30,18 @@ people using 80-column terminals.
 	defaults to UTF-8.
 
 --no-notes::
---show-notes::
+--show-notes[=<ref>]::
 	Show the notes (see linkgit:git-notes[1]) that annotate the
 	commit, when showing the commit log message.  This is the default
 	for `git log`, `git show` and `git whatchanged` commands when
 	there is no `--pretty`, `--format` nor `--oneline` option is
 	given on the command line.
++
+With an optional argument, add this ref to the list of notes.  The ref
+is taken to be in `refs/notes/` if it is not qualified.
+
+--[no-]standard-notes::
+	Enable or disable populating the notes ref list from the
+	'core.notesRef' and 'notes.displayRef' variables (or
+	corresponding environment overrides).  Enabled by default.
+	See linkgit:git-config[1].

builtin.h

@@ -20,6 +20,23 @@ extern int commit_tree(const char *msg, unsigned char *tree,
 		struct commit_list *parents, unsigned char *ret,
 		const char *author);
 extern int commit_notes(struct notes_tree *t, const char *msg);
+
+struct notes_rewrite_cfg {
+	struct notes_tree **trees;
+	const char *cmd;
+	int enabled;
+	combine_notes_fn *combine;
+	struct string_list *refs;
+	int refs_from_env;
+	int mode_from_env;
+};
+
+combine_notes_fn *parse_combine_notes_fn(const char *v);
+struct notes_rewrite_cfg *init_copy_notes_for_rewrite(const char *cmd);
+int copy_note_for_rewrite(struct notes_rewrite_cfg *c,
+			  const unsigned char *from_obj, const unsigned char *to_obj);
+void finish_copy_notes_for_rewrite(struct notes_rewrite_cfg *c);
+
 extern int check_pager_config(const char *cmd);
 
 extern int cmd_add(int argc, const char **argv, const char *prefix);

builtin/commit.c

@@ -66,6 +66,7 @@ static char *edit_message, *use_message;
 static char *author_name, *author_email, *author_date;
 static int all, edit_flag, also, interactive, only, amend, signoff;
 static int quiet, verbose, no_verify, allow_empty, dry_run, renew_authorship;
+static int no_post_rewrite;
 static char *untracked_files_arg, *force_date;
 /*
  * The default commit message cleanup mode will remove the lines
@@ -137,6 +138,7 @@ static struct option builtin_commit_options[] = {
 	OPT_BOOLEAN('z', "null", &null_termination,
 		    "terminate entries with NUL"),
 	OPT_BOOLEAN(0, "amend", &amend, "amend previous commit"),
+	OPT_BOOLEAN(0, "no-post-rewrite", &no_post_rewrite, "bypass post-rewrite hook"),
 	{ OPTION_STRING, 'u', "untracked-files", &untracked_files_arg, "mode", "show untracked files, optional modes: all, normal, no. (Default: all)", PARSE_OPT_OPTARG, NULL, (intptr_t)"all" },
 	OPT_BOOLEAN(0, "allow-empty", &allow_empty, "ok to record an empty change"),
 	/* end commit contents options */
@@ -1160,6 +1162,40 @@ static int git_commit_config(const char *k, const char *v, void *cb)
 	return git_status_config(k, v, s);
 }
 
+static const char post_rewrite_hook[] = "hooks/post-rewrite";
+
+static int run_rewrite_hook(const unsigned char *oldsha1,
+			    const unsigned char *newsha1)
+{
+	/* oldsha1 SP newsha1 LF NUL */
+	static char buf[2*40 + 3];
+	struct child_process proc;
+	const char *argv[3];
+	int code;
+	size_t n;
+
+	if (access(git_path(post_rewrite_hook), X_OK) < 0)
+		return 0;
+
+	argv[0] = git_path(post_rewrite_hook);
+	argv[1] = "amend";
+	argv[2] = NULL;
+
+	memset(&proc, 0, sizeof(proc));
+	proc.argv = argv;
+	proc.in = -1;
+	proc.stdout_to_stderr = 1;
+
+	code = start_command(&proc);
+	if (code)
+		return code;
+	n = snprintf(buf, sizeof(buf), "%s %s\n",
+		     sha1_to_hex(oldsha1), sha1_to_hex(newsha1));
+	write_in_full(proc.in, buf, n);
+	close(proc.in);
+	return finish_command(&proc);
+}
+
 int cmd_commit(int argc, const char **argv, const char *prefix)
 {
 	struct strbuf sb = STRBUF_INIT;
@@ -1303,6 +1339,15 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 
 	rerere(0);
 	run_hook(get_index_file(), "post-commit", NULL);
+	if (amend && !no_post_rewrite) {
+		struct notes_rewrite_cfg *cfg;
+		cfg = init_copy_notes_for_rewrite("amend");
+		if (cfg) {
+			copy_note_for_rewrite(cfg, head_sha1, commit_sha1);
+			finish_copy_notes_for_rewrite(cfg);
+		}
+		run_rewrite_hook(head_sha1, commit_sha1);
+	}
 	if (!quiet)
 		print_summary(prefix, commit_sha1);
 

builtin/log.c

@@ -60,6 +60,8 @@ static void cmd_log_init(int argc, const char **argv, const char *prefix,
 
 	if (!rev->show_notes_given && !rev->pretty_given)
 		rev->show_notes = 1;
+	if (rev->show_notes)
+		init_display_notes(&rev->notes_opt);
 
 	if (rev->diffopt.pickaxe || rev->diffopt.filter)
 		rev->always_show_header = 0;
@@ -1105,6 +1107,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 	if (!DIFF_OPT_TST(&rev.diffopt, TEXT) && !no_binary_diff)
 		DIFF_OPT_SET(&rev.diffopt, BINARY);
 
+	if (rev.show_notes)
+		init_display_notes(&rev.notes_opt);
+
 	if (!use_stdout)
 		output_directory = set_outdir(prefix, output_directory);
 

builtin/notes.c

@@ -16,6 +16,7 @@
 #include "exec_cmd.h"
 #include "run-command.h"
 #include "parse-options.h"
+#include "string-list.h"
 
 static const char * const git_notes_usage[] = {
 	"git notes [list [<object>]]",
@@ -239,6 +240,8 @@ int commit_notes(struct notes_tree *t, const char *msg)
 		t = &default_notes_tree;
 	if (!t->initialized || !t->ref || !*t->ref)
 		die("Cannot commit uninitialized/unreferenced notes tree");
+	if (!t->dirty)
+		return 0; /* don't have to commit an unchanged tree */
 
 	/* Prepare commit message and reflog message */
 	strbuf_addstr(&buf, "notes: "); /* commit message starts at index 7 */
@@ -269,6 +272,161 @@ int commit_notes(struct notes_tree *t, const char *msg)
 	return 0;
 }
 
+
+combine_notes_fn *parse_combine_notes_fn(const char *v)
+{
+	if (!strcasecmp(v, "overwrite"))
+		return combine_notes_overwrite;
+	else if (!strcasecmp(v, "ignore"))
+		return combine_notes_ignore;
+	else if (!strcasecmp(v, "concatenate"))
+		return combine_notes_concatenate;
+	else
+		return NULL;
+}
+
+static int notes_rewrite_config(const char *k, const char *v, void *cb)
+{
+	struct notes_rewrite_cfg *c = cb;
+	if (!prefixcmp(k, "notes.rewrite.") && !strcmp(k+14, c->cmd)) {
+		c->enabled = git_config_bool(k, v);
+		return 0;
+	} else if (!c->mode_from_env && !strcmp(k, "notes.rewritemode")) {
+		if (!v)
+			config_error_nonbool(k);
+		c->combine = parse_combine_notes_fn(v);
+		if (!c->combine) {
+			error("Bad notes.rewriteMode value: '%s'", v);
+			return 1;
+		}
+		return 0;
+	} else if (!c->refs_from_env && !strcmp(k, "notes.rewriteref")) {
+		/* note that a refs/ prefix is implied in the
+		 * underlying for_each_glob_ref */
+		if (!prefixcmp(v, "refs/notes/"))
+			string_list_add_refs_by_glob(c->refs, v);
+		else
+			warning("Refusing to rewrite notes in %s"
+				" (outside of refs/notes/)", v);
+		return 0;
+	}
+
+	return 0;
+}
+
+
+struct notes_rewrite_cfg *init_copy_notes_for_rewrite(const char *cmd)
+{
+	struct notes_rewrite_cfg *c = xmalloc(sizeof(struct notes_rewrite_cfg));
+	const char *rewrite_mode_env = getenv(GIT_NOTES_REWRITE_MODE_ENVIRONMENT);
+	const char *rewrite_refs_env = getenv(GIT_NOTES_REWRITE_REF_ENVIRONMENT);
+	c->cmd = cmd;
+	c->enabled = 1;
+	c->combine = combine_notes_concatenate;
+	c->refs = xcalloc(1, sizeof(struct string_list));
+	c->refs->strdup_strings = 1;
+	c->refs_from_env = 0;
+	c->mode_from_env = 0;
+	if (rewrite_mode_env) {
+		c->mode_from_env = 1;
+		c->combine = parse_combine_notes_fn(rewrite_mode_env);
+		if (!c->combine)
+			error("Bad " GIT_NOTES_REWRITE_MODE_ENVIRONMENT
+			      " value: '%s'", rewrite_mode_env);
+	}
+	if (rewrite_refs_env) {
+		c->refs_from_env = 1;
+		string_list_add_refs_from_colon_sep(c->refs, rewrite_refs_env);
+	}
+	git_config(notes_rewrite_config, c);
+	if (!c->enabled || !c->refs->nr) {
+		string_list_clear(c->refs, 0);
+		free(c->refs);
+		free(c);
+		return NULL;
+	}
+	c->trees = load_notes_trees(c->refs);
+	string_list_clear(c->refs, 0);
+	free(c->refs);
+	return c;
+}
+
+int copy_note_for_rewrite(struct notes_rewrite_cfg *c,
+			  const unsigned char *from_obj, const unsigned char *to_obj)
+{
+	int ret = 0;
+	int i;
+	for (i = 0; c->trees[i]; i++)
+		ret = copy_note(c->trees[i], from_obj, to_obj, 1, c->combine) || ret;
+	return ret;
+}
+
+void finish_copy_notes_for_rewrite(struct notes_rewrite_cfg *c)
+{
+	int i;
+	for (i = 0; c->trees[i]; i++) {
+		commit_notes(c->trees[i], "Notes added by 'git notes copy'");
+		free_notes(c->trees[i]);
+	}
+	free(c->trees);
+	free(c);
+}
+
+int notes_copy_from_stdin(int force, const char *rewrite_cmd)
+{
+	struct strbuf buf = STRBUF_INIT;
+	struct notes_rewrite_cfg *c = NULL;
+	struct notes_tree *t;
+	int ret = 0;
+
+	if (rewrite_cmd) {
+		c = init_copy_notes_for_rewrite(rewrite_cmd);
+		if (!c)
+			return 0;
+	} else {
+		init_notes(NULL, NULL, NULL, 0);
+		t = &default_notes_tree;
+	}
+
+	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
+		unsigned char from_obj[20], to_obj[20];
+		struct strbuf **split;
+		int err;
+
+		split = strbuf_split(&buf, ' ');
+		if (!split[0] || !split[1])
+			die("Malformed input line: '%s'.", buf.buf);
+		strbuf_rtrim(split[0]);
+		strbuf_rtrim(split[1]);
+		if (get_sha1(split[0]->buf, from_obj))
+			die("Failed to resolve '%s' as a valid ref.", split[0]->buf);
+		if (get_sha1(split[1]->buf, to_obj))
+			die("Failed to resolve '%s' as a valid ref.", split[1]->buf);
+
+		if (rewrite_cmd)
+			err = copy_note_for_rewrite(c, from_obj, to_obj);
+		else
+			err = copy_note(t, from_obj, to_obj, force,
+					combine_notes_overwrite);
+
+		if (err) {
+			error("Failed to copy notes from '%s' to '%s'",
+			      split[0]->buf, split[1]->buf);
+			ret = 1;
+		}
+
+		strbuf_list_free(split);
+	}
+
+	if (!rewrite_cmd) {
+		commit_notes(t, "Notes added by 'git notes copy'");
+		free_notes(t);
+	} else {
+		finish_copy_notes_for_rewrite(c);
+	}
+	return ret;
+}
+
 int cmd_notes(int argc, const char **argv, const char *prefix)
 {
 	struct notes_tree *t;
@@ -278,9 +436,11 @@ int cmd_notes(int argc, const char **argv, const char *prefix)
 	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 contents options"),
 		{ OPTION_CALLBACK, 'm', "message", &msg, "MSG",
@@ -297,6 +457,11 @@ int cmd_notes(int argc, const char **argv, const char *prefix)
 			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()
 	};
 
@@ -304,6 +469,19 @@ int cmd_notes(int argc, const char **argv, const char *prefix)
 
 	argc = parse_options(argc, argv, prefix, options, git_notes_usage, 0);
 
+	if (override_notes_ref) {
+		struct strbuf sb = STRBUF_INIT;
+		if (!prefixcmp(override_notes_ref, "refs/notes/"))
+			/* we're happy */;
+		else if (!prefixcmp(override_notes_ref, "notes/"))
+			strbuf_addstr(&sb, "refs/");
+		else
+			strbuf_addstr(&sb, "refs/notes/");
+		strbuf_addstr(&sb, override_notes_ref);
+		setenv("GIT_NOTES_REF", sb.buf, 1);
+		strbuf_release(&sb);
+	}
+
 	if (argc && !strcmp(argv[0], "list"))
 		list = 1;
 	else if (argc && !strcmp(argv[0], "add"))
@@ -345,8 +523,25 @@ int cmd_notes(int argc, const char **argv, const char *prefix)
 		usage_with_options(git_notes_usage, options);
 	}
 
+	if (!copy && rewrite_cmd) {
+		error("cannot use --for-rewrite with %s subcommand.", argv[0]);
+		usage_with_options(git_notes_usage, options);
+	}
+	if (!copy && from_stdin) {
+		error("cannot use --stdin with %s subcommand.", argv[0]);
+		usage_with_options(git_notes_usage, options);
+	}
+
 	if (copy) {
 		const char *from_ref;
+		if (from_stdin || rewrite_cmd) {
+			if (argc > 1) {
+				error("too many parameters");
+				usage_with_options(git_notes_usage, options);
+			} else {
+				return notes_copy_from_stdin(force, rewrite_cmd);
+			}
+		}
 		if (argc < 3) {
 			error("too few parameters");
 			usage_with_options(git_notes_usage, options);

cache.h

@@ -387,6 +387,9 @@ static inline enum object_type object_type(unsigned int mode)
 #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

git-am.sh

@@ -593,6 +593,7 @@ do
 			echo "Patch is empty.  Was it split wrong?"
 			stop_here $this
 		}
+		rm -f "$dotest/original-commit"
 		if test -f "$dotest/rebasing" &&
 			commit=$(sed -e 's/^From \([0-9a-f]*\) .*/\1/' \
 				-e q "$dotest/$msgnum") &&
@@ -600,6 +601,7 @@ do
 		then
 			git cat-file commit "$commit" |
 			sed -e '1,/^$/d' >"$dotest/msg-clean"
+			echo "$commit" > "$dotest/original-commit"
 		else
 			{
 				sed -n '/^Subject/ s/Subject: //p' "$dotest/info"
@@ -783,6 +785,10 @@ do
 	git update-ref -m "$GIT_REFLOG_ACTION: $FIRSTLINE" HEAD $commit $parent ||
 	stop_here $this
 
+	if test -f "$dotest/original-commit"; then
+		echo "$(cat "$dotest/original-commit") $commit" >> "$dotest/rewritten"
+	fi
+
 	if test -x "$GIT_DIR"/hooks/post-applypatch
 	then
 		"$GIT_DIR"/hooks/post-applypatch
@@ -791,5 +797,12 @@ do
 	go_next
 done
 
+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

git-rebase--interactive.sh

@@ -96,6 +96,13 @@ AUTHOR_SCRIPT="$DOTEST"/author-script
 # command is processed, this file is deleted.
 AMEND="$DOTEST"/amend
 
+# For the post-rewrite hook, we make a list of rewritten commits and
+# their new sha1s.  The rewritten-pending list keeps the sha1s of
+# commits that have been processed, but not committed yet,
+# e.g. because they are waiting for a 'squash' command.
+REWRITTEN_LIST="$DOTEST"/rewritten-list
+REWRITTEN_PENDING="$DOTEST"/rewritten-pending
+
 PRESERVE_MERGES=
 STRATEGY=
 ONTO=
@@ -198,6 +205,7 @@ make_patch () {
 }
 
 die_with_patch () {
+	echo "$1" > "$DOTEST"/stopped-sha
 	make_patch "$1"
 	git rerere
 	die "$2"
@@ -348,6 +356,7 @@ pick_one_preserving_merges () {
 				printf "%s\n" "$msg" > "$GIT_DIR"/MERGE_MSG
 				die_with_patch $sha1 "Error redoing merge $sha1"
 			fi
+			echo "$sha1 $(git rev-parse HEAD^0)" >> "$REWRITTEN_LIST"
 			;;
 		*)
 			output git cherry-pick "$@" ||
@@ -425,6 +434,26 @@ die_failed_squash() {
 	die_with_patch $1 ""
 }
 
+flush_rewritten_pending() {
+	test -s "$REWRITTEN_PENDING" || return
+	newsha1="$(git rev-parse HEAD^0)"
+	sed "s/$/ $newsha1/" < "$REWRITTEN_PENDING" >> "$REWRITTEN_LIST"
+	rm -f "$REWRITTEN_PENDING"
+}
+
+record_in_rewritten() {
+	oldsha1="$(git rev-parse $1)"
+	echo "$oldsha1" >> "$REWRITTEN_PENDING"
+
+	case "$(peek_next_command)" in
+	    squash|s|fixup|f)
+		;;
+	    *)
+		flush_rewritten_pending
+		;;
+	esac
+}
+
 do_next () {
 	rm -f "$MSG" "$AUTHOR_SCRIPT" "$AMEND" || exit
 	read command sha1 rest < "$TODO"
@@ -438,6 +467,7 @@ do_next () {
 		mark_action_done
 		pick_one $sha1 ||
 			die_with_patch $sha1 "Could not apply $sha1... $rest"
+		record_in_rewritten $sha1
 		;;
 	reword|r)
 		comment_for_reflog reword
@@ -445,7 +475,8 @@ do_next () {
 		mark_action_done
 		pick_one $sha1 ||
 			die_with_patch $sha1 "Could not apply $sha1... $rest"
-		git commit --amend
+		git commit --amend --no-post-rewrite
+		record_in_rewritten $sha1
 		;;
 	edit|e)
 		comment_for_reflog edit
@@ -453,6 +484,7 @@ do_next () {
 		mark_action_done
 		pick_one $sha1 ||
 			die_with_patch $sha1 "Could not apply $sha1... $rest"
+		echo "$1" > "$DOTEST"/stopped-sha
 		make_patch $sha1
 		git rev-parse --verify HEAD > "$AMEND"
 		warn "Stopped at $sha1... $rest"
@@ -509,6 +541,7 @@ do_next () {
 			rm -f "$SQUASH_MSG" "$FIXUP_MSG"
 			;;
 		esac
+		record_in_rewritten $sha1
 		;;
 	*)
 		warn "Unknown command: $command $sha1 $rest"
@@ -537,6 +570,15 @@ do_next () {
 		test ! -f "$DOTEST"/verbose ||
 			git diff-tree --stat $(cat "$DOTEST"/head)..HEAD
 	} &&
+	{
+		git notes copy --for-rewrite=rebase < "$REWRITTEN_LIST" ||
+		true # we don't care if this copying failed
+	} &&
+	if test -x "$GIT_DIR"/hooks/post-rewrite &&
+		test -s "$REWRITTEN_LIST"; then
+		"$GIT_DIR"/hooks/post-rewrite rebase < "$REWRITTEN_LIST"
+		true # we don't care if this hook failed
+	fi &&
 	rm -rf "$DOTEST" &&
 	git gc --auto &&
 	warn "Successfully rebased and updated $HEADNAME."
@@ -571,7 +613,12 @@ skip_unnecessary_picks () {
 		esac
 		echo "$command${sha1:+ }$sha1${rest:+ }$rest" >&$fd
 	done <"$TODO" >"$TODO.new" 3>>"$DONE" &&
-	mv -f "$TODO".new "$TODO" ||
+	mv -f "$TODO".new "$TODO" &&
+	case "$(peek_next_command)" in
+	squash|s|fixup|f)
+		record_in_rewritten "$ONTO"
+		;;
+	esac ||
 	die "Could not skip unnecessary pick commands"
 }
 
@@ -685,6 +732,7 @@ first and then run 'git rebase --continue' again."
 				test -n "$amend" && git reset --soft $amend
 				die "Could not commit staged changes."
 			}
+			record_in_rewritten "$(cat "$DOTEST"/stopped-sha)"
 		fi
 
 		require_clean_work_tree

git-rebase.sh

@@ -79,6 +79,7 @@ continue_merge () {
 		then
 			printf "Committed: %0${prec}d " $msgnum
 		fi
+		echo "$cmt $(git rev-parse HEAD^0)" >> "$dotest/rewritten"
 	else
 		if test -z "$GIT_QUIET"
 		then
@@ -151,6 +152,11 @@ move_to_original_branch () {
 
 finish_rb_merge () {
 	move_to_original_branch
+	git notes copy --for-rewrite=rebase < "$dotest"/rewritten
+	if test -x "$GIT_DIR"/hooks/post-rewrite &&
+		test -s "$dotest"/rewritten; then
+		"$GIT_DIR"/hooks/post-rewrite rebase < "$dotest"/rewritten
+	fi
 	rm -r "$dotest"
 	say All done.
 }

notes.c

@@ -5,6 +5,8 @@
 #include "utf8.h"
 #include "strbuf.h"
 #include "tree-walk.h"
+#include "string-list.h"
+#include "refs.h"
 
 /*
  * Use a non-balancing simple 16-tree structure with struct int_node as
@@ -68,6 +70,9 @@ struct non_note {
 
 struct notes_tree default_notes_tree;
 
+static struct string_list display_notes_refs;
+static struct notes_tree **display_notes_trees;
+
 static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
 		struct int_node *node, unsigned int n);
 
@@ -828,6 +833,83 @@ int combine_notes_ignore(unsigned char *cur_sha1,
 	return 0;
 }
 
+static int string_list_add_one_ref(const char *path, const unsigned char *sha1,
+				   int flag, void *cb)
+{
+	struct string_list *refs = cb;
+	if (!unsorted_string_list_has_string(refs, path))
+		string_list_append(path, refs);
+	return 0;
+}
+
+void string_list_add_refs_by_glob(struct string_list *list, const char *glob)
+{
+	if (has_glob_specials(glob)) {
+		for_each_glob_ref(string_list_add_one_ref, glob, list);
+	} else {
+		unsigned char sha1[20];
+		if (get_sha1(glob, sha1))
+			warning("notes ref %s is invalid", glob);
+		if (!unsorted_string_list_has_string(list, glob))
+			string_list_append(glob, list);
+	}
+}
+
+void string_list_add_refs_from_colon_sep(struct string_list *list,
+					 const char *globs)
+{
+	struct strbuf globbuf = STRBUF_INIT;
+	struct strbuf **split;
+	int i;
+
+	strbuf_addstr(&globbuf, globs);
+	split = strbuf_split(&globbuf, ':');
+
+	for (i = 0; split[i]; i++) {
+		if (!split[i]->len)
+			continue;
+		if (split[i]->buf[split[i]->len-1] == ':')
+			strbuf_setlen(split[i], split[i]->len-1);
+		string_list_add_refs_by_glob(list, split[i]->buf);
+	}
+
+	strbuf_list_free(split);
+	strbuf_release(&globbuf);
+}
+
+static int string_list_add_refs_from_list(struct string_list_item *item,
+					  void *cb)
+{
+	struct string_list *list = cb;
+	string_list_add_refs_by_glob(list, item->string);
+	return 0;
+}
+
+static int notes_display_config(const char *k, const char *v, void *cb)
+{
+	int *load_refs = cb;
+
+	if (*load_refs && !strcmp(k, "notes.displayref")) {
+		if (!v)
+			config_error_nonbool(k);
+		string_list_add_refs_by_glob(&display_notes_refs, v);
+	}
+
+	return 0;
+}
+
+static const char *default_notes_ref(void)
+{
+	const char *notes_ref = NULL;
+	if (!notes_ref)
+		notes_ref = getenv(GIT_NOTES_REF_ENVIRONMENT);
+	if (!notes_ref)
+		notes_ref = notes_ref_name; /* value of core.notesRef config */
+	if (!notes_ref)
+		notes_ref = GIT_NOTES_DEFAULT_REF;
+	return notes_ref;
+}
+
 void init_notes(struct notes_tree *t, const char *notes_ref,
 		combine_notes_fn combine_notes, int flags)
 {
@@ -840,11 +922,7 @@ void init_notes(struct notes_tree *t, const char *notes_ref,
 	assert(!t->initialized);
 
 	if (!notes_ref)
-		notes_ref = getenv(GIT_NOTES_REF_ENVIRONMENT);
-	if (!notes_ref)
-		notes_ref = notes_ref_name; /* value of core.notesRef config */
-	if (!notes_ref)
-		notes_ref = GIT_NOTES_DEFAULT_REF;
+		notes_ref = default_notes_ref();
 
 	if (!combine_notes)
 		combine_notes = combine_notes_concatenate;
@@ -855,6 +933,7 @@ void init_notes(struct notes_tree *t, const char *notes_ref,
 	t->ref = notes_ref ? xstrdup(notes_ref) : NULL;
 	t->combine_notes = combine_notes;
 	t->initialized = 1;
+	t->dirty = 0;
 
 	if (flags & NOTES_INIT_EMPTY || !notes_ref ||
 	    read_ref(notes_ref, object_sha1))
@@ -868,6 +947,63 @@ void init_notes(struct notes_tree *t, const char *notes_ref,
 	load_subtree(t, &root_tree, t->root, 0);
 }
 
+struct load_notes_cb_data {
+	int counter;
+	struct notes_tree **trees;
+};
+
+static int load_one_display_note_ref(struct string_list_item *item,
+				     void *cb_data)
+{
+	struct load_notes_cb_data *c = cb_data;
+	struct notes_tree *t = xcalloc(1, sizeof(struct notes_tree));
+	init_notes(t, item->string, combine_notes_ignore, 0);
+	c->trees[c->counter++] = t;
+	return 0;
+}
+
+struct notes_tree **load_notes_trees(struct string_list *refs)
+{
+	struct notes_tree **trees;
+	struct load_notes_cb_data cb_data;
+	trees = xmalloc((refs->nr+1) * sizeof(struct notes_tree *));
+	cb_data.counter = 0;
+	cb_data.trees = trees;
+	for_each_string_list(load_one_display_note_ref, refs, &cb_data);
+	trees[cb_data.counter] = NULL;
+	return trees;
+}
+
+void init_display_notes(struct display_notes_opt *opt)
+{
+	char *display_ref_env;
+	int load_config_refs = 0;
+	display_notes_refs.strdup_strings = 1;
+
+	assert(!display_notes_trees);
+
+	if (!opt || !opt->suppress_default_notes) {
+		string_list_append(default_notes_ref(), &display_notes_refs);
+		display_ref_env = getenv(GIT_NOTES_DISPLAY_REF_ENVIRONMENT);
+		if (display_ref_env) {
+			string_list_add_refs_from_colon_sep(&display_notes_refs,
+							    display_ref_env);
+			load_config_refs = 0;
+		} else
+			load_config_refs = 1;
+	}
+
+	git_config(notes_display_config, &load_config_refs);
+
+	if (opt && opt->extra_notes_refs)
+		for_each_string_list(string_list_add_refs_from_list,
+				     opt->extra_notes_refs,
+				     &display_notes_refs);
+
+	display_notes_trees = load_notes_trees(&display_notes_refs);
+	string_list_clear(&display_notes_refs, 0);
+}
+
 void add_note(struct notes_tree *t, const unsigned char *object_sha1,
 		const unsigned char *note_sha1, combine_notes_fn combine_notes)
 {
@@ -876,6 +1012,7 @@ void add_note(struct notes_tree *t, const unsigned char *object_sha1,
 	if (!t)
 		t = &default_notes_tree;
 	assert(t->initialized);
+	t->dirty = 1;
 	if (!combine_notes)
 		combine_notes = t->combine_notes;
 	l = (struct leaf_node *) xmalloc(sizeof(struct leaf_node));
@@ -891,6 +1028,7 @@ void remove_note(struct notes_tree *t, const unsigned char *object_sha1)
 	if (!t)
 		t = &default_notes_tree;
 	assert(t->initialized);
+	t->dirty = 1;
 	hashcpy(l.key_sha1, object_sha1);
 	hashclr(l.val_sha1);
 	note_tree_remove(t, t->root, 0, &l);
@@ -1016,8 +1154,18 @@ void format_note(struct notes_tree *t, const unsigned char *object_sha1,
 	if (msglen && msg[msglen - 1] == '\n')
 		msglen--;
 
-	if (flags & NOTES_SHOW_HEADER)
-		strbuf_addstr(sb, "\nNotes:\n");
+	if (flags & NOTES_SHOW_HEADER) {
+		const char *ref = t->ref;
+		if (!ref || !strcmp(ref, GIT_NOTES_DEFAULT_REF)) {
+			strbuf_addstr(sb, "\nNotes:\n");
+		} else {
+			if (!prefixcmp(ref, "refs/"))
+				ref += 5;
+			if (!prefixcmp(ref, "notes/"))
+				ref += 6;
+			strbuf_addf(sb, "\nNotes (%s):\n", ref);
+		}
+	}
 
 	for (msg_p = msg; msg_p < msg + msglen; msg_p += linelen + 1) {
 		linelen = strchrnul(msg_p, '\n') - msg_p;
@@ -1030,3 +1178,31 @@ void format_note(struct notes_tree *t, const unsigned char *object_sha1,
 
 	free(msg);
 }
+
+void format_display_notes(const unsigned char *object_sha1,
+			  struct strbuf *sb, const char *output_encoding, int flags)
+{
+	int i;
+	assert(display_notes_trees);
+	for (i = 0; display_notes_trees[i]; i++)
+		format_note(display_notes_trees[i], object_sha1, sb,
+			    output_encoding, flags);
+}
+
+int copy_note(struct notes_tree *t,
+	      const unsigned char *from_obj, const unsigned char *to_obj,
+	      int force, combine_notes_fn combine_fn)
+{
+	const unsigned char *note = get_note(t, from_obj);
+	const unsigned char *existing_note = get_note(t, to_obj);
+
+	if (!force && existing_note)
+		return 1;
+
+	if (note)
+		add_note(t, to_obj, note, combine_fn);
+	else if (existing_note)
+		add_note(t, to_obj, null_sha1, combine_fn);
+
+	return 0;
+}

notes.h

@@ -40,6 +40,7 @@ extern struct notes_tree {
 	char *ref;
 	combine_notes_fn *combine_notes;
 	int initialized;
+	int dirty;
 } default_notes_tree;
 
 /*
@@ -99,6 +100,15 @@ void remove_note(struct notes_tree *t, const unsigned char *object_sha1);
 const unsigned char *get_note(struct notes_tree *t,
 		const unsigned char *object_sha1);
 
+/*
+ * Copy a note from one object to another in the given notes_tree.
+ *
+ * Fails if the to_obj already has a note unless 'force' is true.
+ */
+int copy_note(struct notes_tree *t,
+	      const unsigned char *from_obj, const unsigned char *to_obj,
+	      int force, combine_notes_fn combine_fn);
+
 /*
  * Flags controlling behaviour of for_each_note()
  *
@@ -198,4 +208,59 @@ void free_notes(struct notes_tree *t);
 void format_note(struct notes_tree *t, const unsigned char *object_sha1,
 		struct strbuf *sb, const char *output_encoding, int flags);
 
+
+struct string_list;
+
+struct display_notes_opt {
+	int suppress_default_notes:1;
+	struct string_list *extra_notes_refs;
+};
+
+/*
+ * Load the notes machinery for displaying several notes trees.
+ *
+ * If 'opt' is not NULL, then it specifies additional settings for the
+ * displaying:
+ *
+ * - suppress_default_notes indicates that the notes from
+ *   core.notesRef and notes.displayRef should not be loaded.
+ *
+ * - extra_notes_refs may contain a list of globs (in the same style
+ *   as notes.displayRef) where notes should be loaded from.
+ */
+void init_display_notes(struct display_notes_opt *opt);
+
+/*
+ * Append notes for the given 'object_sha1' from all trees set up by
+ * init_display_notes() to 'sb'.  The 'flags' are a bitwise
+ * combination of
+ *
+ * - NOTES_SHOW_HEADER: add a 'Notes (refname):' header
+ *
+ * - NOTES_INDENT: indent the notes by 4 places
+ *
+ * You *must* call init_display_notes() before using this function.
+ */
+void format_display_notes(const unsigned char *object_sha1,
+			  struct strbuf *sb, const char *output_encoding, int flags);
+
+/*
+ * Load the notes tree from each ref listed in 'refs'.  The output is
+ * an array of notes_tree*, terminated by a NULL.
+ */
+struct notes_tree **load_notes_trees(struct string_list *refs);
+
+/*
+ * Add all refs that match 'glob' to the 'list'.
+ */
+void string_list_add_refs_by_glob(struct string_list *list, const char *glob);
+
+/*
+ * Add all refs from a colon-separated glob list 'globs' to the end of
+ * 'list'.  Empty components are ignored.  This helper is used to
+ * parse GIT_NOTES_DISPLAY_REF style environment variables.
+ */
+void string_list_add_refs_from_colon_sep(struct string_list *list,
+					 const char *globs);
+
 #endif

pretty.c

@@ -775,7 +775,7 @@ static size_t format_commit_one(struct strbuf *sb, const char *placeholder,
 		}
 		return 0;	/* unknown %g placeholder */
 	case 'N':
-		format_note(NULL, commit->object.sha1, sb,
+		format_display_notes(commit->object.sha1, sb,
 			    git_log_output_encoding ? git_log_output_encoding
 						    : git_commit_encoding, 0);
 		return 1;
@@ -1096,8 +1096,8 @@ void pretty_print_commit(enum cmit_fmt fmt, const struct commit *commit,
 		strbuf_addch(sb, '\n');
 
 	if (context->show_notes)
-		format_note(NULL, commit->object.sha1, sb, encoding,
-			    NOTES_SHOW_HEADER | NOTES_INDENT);
+		format_display_notes(commit->object.sha1, sb, encoding,
+				     NOTES_SHOW_HEADER | NOTES_INDENT);
 
 	free(reencoded);
 }

refs.c

@@ -698,7 +698,6 @@ int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 {
 	struct strbuf real_pattern = STRBUF_INIT;
 	struct ref_filter filter;
-	const char *has_glob_specials;
 	int ret;
 
 	if (!prefix && prefixcmp(pattern, "refs/"))
@@ -707,8 +706,7 @@ int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
 		strbuf_addstr(&real_pattern, prefix);
 	strbuf_addstr(&real_pattern, pattern);
 
-	has_glob_specials = strpbrk(pattern, "?*[");
-	if (!has_glob_specials) {
+	if (!has_glob_specials(pattern)) {
 		/* Append implied '/' '*' if not present. */
 		if (real_pattern.buf[real_pattern.len - 1] != '/')
 			strbuf_addch(&real_pattern, '/');

refs.h

@@ -28,6 +28,11 @@ extern int for_each_replace_ref(each_ref_fn, void *);
 extern int for_each_glob_ref(each_ref_fn, const char *pattern, void *);
 extern int for_each_glob_ref_in(each_ref_fn, const char *pattern, const char* prefix, void *);
 
+static inline const char *has_glob_specials(const char *pattern)
+{
+	return strpbrk(pattern, "?*[");
+}
+
 /* can be used to learn about broken ref and symref */
 extern int for_each_rawref(each_ref_fn, void *);
 

revision.c

@@ -12,6 +12,7 @@
 #include "patch-ids.h"
 #include "decorate.h"
 #include "log-tree.h"
+#include "string-list.h"
 
 volatile show_early_output_fn_t show_early_output;
 
@@ -1191,9 +1192,29 @@ static int handle_revision_opt(struct rev_info *revs, int argc, const char **arg
 	} else if (!strcmp(arg, "--show-notes")) {
 		revs->show_notes = 1;
 		revs->show_notes_given = 1;
+	} else if (!prefixcmp(arg, "--show-notes=")) {
+		struct strbuf buf = STRBUF_INIT;
+		revs->show_notes = 1;
+		revs->show_notes_given = 1;
+		if (!revs->notes_opt.extra_notes_refs)
+			revs->notes_opt.extra_notes_refs = xcalloc(1, sizeof(struct string_list));
+		if (!prefixcmp(arg+13, "refs/"))
+			/* happy */;
+		else if (!prefixcmp(arg+13, "notes/"))
+			strbuf_addstr(&buf, "refs/");
+		else
+			strbuf_addstr(&buf, "refs/notes/");
+		strbuf_addstr(&buf, arg+13);
+		string_list_append(strbuf_detach(&buf, NULL),
+				   revs->notes_opt.extra_notes_refs);
 	} else if (!strcmp(arg, "--no-notes")) {
 		revs->show_notes = 0;
 		revs->show_notes_given = 1;
+	} else if (!strcmp(arg, "--standard-notes")) {
+		revs->show_notes_given = 1;
+		revs->notes_opt.suppress_default_notes = 0;
+	} else if (!strcmp(arg, "--no-standard-notes")) {
+		revs->notes_opt.suppress_default_notes = 1;
 	} else if (!strcmp(arg, "--oneline")) {
 		revs->verbose_header = 1;
 		get_commit_format("oneline", revs);

revision.h

@@ -3,6 +3,7 @@
 
 #include "parse-options.h"
 #include "grep.h"
+#include "notes.h"
 
 #define SEEN		(1u<<0)
 #define UNINTERESTING   (1u<<1)
@@ -20,6 +21,7 @@
 
 struct rev_info;
 struct log_info;
+struct string_list;
 
 struct rev_info {
 	/* Starting list */
@@ -126,6 +128,9 @@ struct rev_info {
 	struct reflog_walk_info *reflog_info;
 	struct decoration children;
 	struct decoration merge_simplification;
+
+	/* notes-specific options: which refs to show */
+	struct display_notes_opt notes_opt;
 };
 
 #define REV_TREE_SAME		0

t/t3301-notes.sh

@@ -416,7 +416,7 @@ Date:   Thu Apr 7 15:18:13 2005 -0700
 
     6th
 
-Notes:
+Notes (other):
     other note
 EOF
 
@@ -449,7 +449,139 @@ test_expect_success 'Do not show note when core.notesRef is overridden' '
 	test_cmp expect-not-other output
 '
 
+cat > expect-both << EOF
+commit 387a89921c73d7ed72cd94d179c1c7048ca47756
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:18:13 2005 -0700
+
+    6th
+
+Notes:
+    order test
+
+Notes (other):
+    other note
+
+commit bd1753200303d0a0344be813e504253b3d98e74d
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:17:13 2005 -0700
+
+    5th
+
+Notes:
+    replacement for deleted note
+EOF
+
+test_expect_success 'Show all notes when notes.displayRef=refs/notes/*' '
+	GIT_NOTES_REF=refs/notes/commits git notes add \
+		-m"replacement for deleted note" HEAD^ &&
+	GIT_NOTES_REF=refs/notes/commits git notes add -m"order test" &&
+	git config --unset core.notesRef &&
+	git config notes.displayRef "refs/notes/*" &&
+	git log -2 > output &&
+	test_cmp expect-both output
+'
+
+test_expect_success 'core.notesRef is implicitly in notes.displayRef' '
+	git config core.notesRef refs/notes/commits &&
+	git config notes.displayRef refs/notes/other &&
+	git log -2 > output &&
+	test_cmp expect-both output
+'
+
+test_expect_success 'notes.displayRef can be given more than once' '
+	git config --unset core.notesRef &&
+	git config notes.displayRef refs/notes/commits &&
+	git config --add notes.displayRef refs/notes/other &&
+	git log -2 > output &&
+	test_cmp expect-both output
+'
+
+cat > expect-both-reversed << EOF
+commit 387a89921c73d7ed72cd94d179c1c7048ca47756
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:18:13 2005 -0700
+
+    6th
+
+Notes (other):
+    other note
+
+Notes:
+    order test
+EOF
+
+test_expect_success 'notes.displayRef respects order' '
+	git config core.notesRef refs/notes/other &&
+	git config --unset-all notes.displayRef &&
+	git config notes.displayRef refs/notes/commits &&
+	git log -1 > output &&
+	test_cmp expect-both-reversed output
+'
+
+test_expect_success 'GIT_NOTES_DISPLAY_REF works' '
+	git config --unset-all core.notesRef &&
+	git config --unset-all notes.displayRef &&
+	GIT_NOTES_DISPLAY_REF=refs/notes/commits:refs/notes/other \
+		git log -2 > output &&
+	test_cmp expect-both output
+'
+
+cat > expect-none << EOF
+commit 387a89921c73d7ed72cd94d179c1c7048ca47756
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:18:13 2005 -0700
+
+    6th
+
+commit bd1753200303d0a0344be813e504253b3d98e74d
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:17:13 2005 -0700
+
+    5th
+EOF
+
+test_expect_success 'GIT_NOTES_DISPLAY_REF overrides config' '
+	git config notes.displayRef "refs/notes/*" &&
+	GIT_NOTES_REF= GIT_NOTES_DISPLAY_REF= git log -2 > output &&
+	test_cmp expect-none output
+'
+
+test_expect_success '--show-notes=* adds to GIT_NOTES_DISPLAY_REF' '
+	GIT_NOTES_REF= GIT_NOTES_DISPLAY_REF= git log --show-notes=* -2 > output &&
+	test_cmp expect-both output
+'
+
+cat > expect-commits << EOF
+commit 387a89921c73d7ed72cd94d179c1c7048ca47756
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:18:13 2005 -0700
+
+    6th
+
+Notes:
+    order test
+EOF
+
+test_expect_success '--no-standard-notes' '
+	git log --no-standard-notes --show-notes=commits -1 > output &&
+	test_cmp expect-commits output
+'
+
+test_expect_success '--standard-notes' '
+	git log --no-standard-notes --show-notes=commits \
+		--standard-notes -2 > output &&
+	test_cmp expect-both output
+'
+
+test_expect_success '--show-notes=ref accumulates' '
+	git log --show-notes=other --show-notes=commits \
+		 --no-standard-notes -1 > output &&
+	test_cmp expect-both-reversed output
+'
+
 test_expect_success 'Allow notes on non-commits (trees, blobs, tags)' '
+	git config core.notesRef refs/notes/other &&
 	echo "Note on a tree" > expect
 	git notes add -m "Note on a tree" HEAD: &&
 	git notes show HEAD: > actual &&
@@ -473,7 +605,7 @@ Date:   Thu Apr 7 15:19:13 2005 -0700
 
     7th
 
-Notes:
+Notes (other):
     other note
 EOF
 
@@ -504,7 +636,7 @@ Date:   Thu Apr 7 15:21:13 2005 -0700
 
     9th
 
-Notes:
+Notes (other):
     yet another note
 EOF
 
@@ -534,7 +666,7 @@ Date:   Thu Apr 7 15:21:13 2005 -0700
 
     9th
 
-Notes:
+Notes (other):
     yet another note
 $whitespace
     yet another note
@@ -553,7 +685,7 @@ Date:   Thu Apr 7 15:22:13 2005 -0700
 
     10th
 
-Notes:
+Notes (other):
     other note
 EOF
 
@@ -570,7 +702,7 @@ Date:   Thu Apr 7 15:22:13 2005 -0700
 
     10th
 
-Notes:
+Notes (other):
     other note
 $whitespace
     yet another note
@@ -589,7 +721,7 @@ Date:   Thu Apr 7 15:23:13 2005 -0700
 
     11th
 
-Notes:
+Notes (other):
     other note
 $whitespace
     yet another note
@@ -620,7 +752,7 @@ Date:   Thu Apr 7 15:23:13 2005 -0700
 
     11th
 
-Notes:
+Notes (other):
     yet another note
 $whitespace
     yet another note
@@ -645,4 +777,233 @@ test_expect_success 'cannot copy note from object without notes' '
 	test_must_fail git notes copy HEAD^ HEAD
 '
 
+cat > expect << EOF
+commit e5d4fb5698d564ab8c73551538ecaf2b0c666185
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:25:13 2005 -0700
+
+    13th
+
+Notes (other):
+    yet another note
+$whitespace
+    yet another note
+
+commit 7038787dfe22a14c3867ce816dbba39845359719
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:24:13 2005 -0700
+
+    12th
+
+Notes (other):
+    other note
+$whitespace
+    yet another note
+EOF
+
+test_expect_success 'git notes copy --stdin' '
+	(echo $(git rev-parse HEAD~3) $(git rev-parse HEAD^); \
+	echo $(git rev-parse HEAD~2) $(git rev-parse HEAD)) |
+	git notes copy --stdin &&
+	git log -2 > output &&
+	test_cmp expect output &&
+	test "$(git notes list HEAD)" = "$(git notes list HEAD~2)" &&
+	test "$(git notes list HEAD^)" = "$(git notes list HEAD~3)"
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+commit be28d8b4d9951ad940d229ee3b0b9ee3b1ec273d
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:26:13 2005 -0700
+
+    14th
+EOF
+
+test_expect_success 'git notes copy --for-rewrite (unconfigured)' '
+	test_commit 14th &&
+	test_commit 15th &&
+	(echo $(git rev-parse HEAD~3) $(git rev-parse HEAD^); \
+	echo $(git rev-parse HEAD~2) $(git rev-parse HEAD)) |
+	git notes copy --for-rewrite=foo &&
+	git log -2 > output &&
+	test_cmp expect output
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+Notes (other):
+    yet another note
+$whitespace
+    yet another note
+
+commit be28d8b4d9951ad940d229ee3b0b9ee3b1ec273d
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:26:13 2005 -0700
+
+    14th
+
+Notes (other):
+    other note
+$whitespace
+    yet another note
+EOF
+
+test_expect_success 'git notes copy --for-rewrite (enabled)' '
+	git config notes.rewriteMode overwrite &&
+	git config notes.rewriteRef "refs/notes/*" &&
+	(echo $(git rev-parse HEAD~3) $(git rev-parse HEAD^); \
+	echo $(git rev-parse HEAD~2) $(git rev-parse HEAD)) |
+	git notes copy --for-rewrite=foo &&
+	git log -2 > output &&
+	test_cmp expect output
+'
+
+test_expect_success 'git notes copy --for-rewrite (disabled)' '
+	git config notes.rewrite.bar false &&
+	echo $(git rev-parse HEAD~3) $(git rev-parse HEAD) |
+	git notes copy --for-rewrite=bar &&
+	git log -2 > output &&
+	test_cmp expect output
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+Notes (other):
+    a fresh note
+EOF
+
+test_expect_success 'git notes copy --for-rewrite (overwrite)' '
+	git notes add -f -m"a fresh note" HEAD^ &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+test_expect_success 'git notes copy --for-rewrite (ignore)' '
+	git config notes.rewriteMode ignore &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+Notes (other):
+    a fresh note
+    another fresh note
+EOF
+
+test_expect_success 'git notes copy --for-rewrite (append)' '
+	git notes add -f -m"another fresh note" HEAD^ &&
+	git config notes.rewriteMode concatenate &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+Notes (other):
+    a fresh note
+    another fresh note
+    append 1
+    append 2
+EOF
+
+test_expect_success 'git notes copy --for-rewrite (append two to one)' '
+	git notes add -f -m"append 1" HEAD^ &&
+	git notes add -f -m"append 2" HEAD^^ &&
+	(echo $(git rev-parse HEAD^) $(git rev-parse HEAD);
+	echo $(git rev-parse HEAD^^) $(git rev-parse HEAD)) |
+	git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+test_expect_success 'git notes copy --for-rewrite (append empty)' '
+	git notes remove HEAD^ &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+Notes (other):
+    replacement note 1
+EOF
+
+test_expect_success 'GIT_NOTES_REWRITE_MODE works' '
+	git notes add -f -m"replacement note 1" HEAD^ &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	GIT_NOTES_REWRITE_MODE=overwrite git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+cat > expect << EOF
+commit 37a0d4cba38afef96ba54a3ea567e6dac575700b
+Author: A U Thor <author@example.com>
+Date:   Thu Apr 7 15:27:13 2005 -0700
+
+    15th
+
+Notes (other):
+    replacement note 2
+EOF
+
+test_expect_success 'GIT_NOTES_REWRITE_REF works' '
+	git config notes.rewriteMode overwrite &&
+	git notes add -f -m"replacement note 2" HEAD^ &&
+	git config --unset-all notes.rewriteRef &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	GIT_NOTES_REWRITE_REF=refs/notes/commits:refs/notes/other \
+		git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
+
+test_expect_success 'GIT_NOTES_REWRITE_REF overrides config' '
+	git config notes.rewriteRef refs/notes/other &&
+	git notes add -f -m"replacement note 3" HEAD^ &&
+	echo $(git rev-parse HEAD^) $(git rev-parse HEAD) |
+	GIT_NOTES_REWRITE_REF= git notes copy --for-rewrite=foo &&
+	git log -1 > output &&
+	test_cmp expect output
+'
 test_done

t/t3400-rebase.sh

@@ -151,4 +151,21 @@ test_expect_success 'Rebase a commit that sprinkles CRs in' '
 	git diff --exit-code file-with-cr:CR HEAD:CR
 '
 
+test_expect_success 'rebase can copy notes' '
+	git config notes.rewrite.rebase true &&
+	git config notes.rewriteRef "refs/notes/*" &&
+	test_commit n1 &&
+	test_commit n2 &&
+	test_commit n3 &&
+	git notes add -m"a note" n3 &&
+	git rebase --onto n1 n2 &&
+	test "a note" = "$(git notes show HEAD)"
+'
+
+test_expect_success 'rebase -m can copy notes' '
+	git reset --hard n3 &&
+	git rebase -m --onto n1 n2 &&
+	test "a note" = "$(git notes show HEAD)"
+'
+
 test_done

t/t3404-rebase-interactive.sh

@@ -553,4 +553,28 @@ test_expect_success 'reword' '
 	git show HEAD~2 | grep "C changed"
 '
 
+test_expect_success 'rebase -i can copy notes' '
+	git config notes.rewrite.rebase true &&
+	git config notes.rewriteRef "refs/notes/*" &&
+	test_commit n1 &&
+	test_commit n2 &&
+	test_commit n3 &&
+	git notes add -m"a note" n3 &&
+	git rebase --onto n1 n2 &&
+	test "a note" = "$(git notes show HEAD)"
+'
+
+cat >expect <<EOF
+an earlier note
+a note
+EOF
+
+test_expect_success 'rebase -i can copy notes over a fixup' '
+	git reset --hard n3 &&
+	git notes add -m"an earlier note" n2 &&
+	GIT_NOTES_REWRITE_MODE=concatenate FAKE_LINES="1 fixup 2" git rebase -i n1 &&
+	git notes show > output &&
+	test_cmp expect output
+'
+
 test_done

t/t5407-post-rewrite-hook.sh

@@ -0,0 +1,183 @@
+#!/bin/sh
+#
+# Copyright (c) 2010 Thomas Rast
+#
+
+test_description='Test the post-rewrite hook.'
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+	test_commit A foo A &&
+	test_commit B foo B &&
+	test_commit C foo C &&
+	test_commit D foo D
+'
+
+mkdir .git/hooks
+
+cat >.git/hooks/post-rewrite <<EOF
+#!/bin/sh
+echo \$@ > "$TRASH_DIRECTORY"/post-rewrite.args
+cat > "$TRASH_DIRECTORY"/post-rewrite.data
+EOF
+chmod u+x .git/hooks/post-rewrite
+
+clear_hook_input () {
+	rm -f post-rewrite.args post-rewrite.data
+}
+
+verify_hook_input () {
+	test_cmp "$TRASH_DIRECTORY"/post-rewrite.args expected.args &&
+	test_cmp "$TRASH_DIRECTORY"/post-rewrite.data expected.data
+}
+
+test_expect_success 'git commit --amend' '
+	clear_hook_input &&
+	echo "D new message" > newmsg &&
+	oldsha=$(git rev-parse HEAD^0) &&
+	git commit -Fnewmsg --amend &&
+	echo amend > expected.args &&
+	echo $oldsha $(git rev-parse HEAD^0) > expected.data &&
+	verify_hook_input
+'
+
+test_expect_success 'git commit --amend --no-post-rewrite' '
+	clear_hook_input &&
+	echo "D new message again" > newmsg &&
+	git commit --no-post-rewrite -Fnewmsg --amend &&
+	test ! -f post-rewrite.args &&
+	test ! -f post-rewrite.data
+'
+
+test_expect_success 'git rebase' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_must_fail git rebase --onto A B &&
+	echo C > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse C) $(git rev-parse HEAD^)
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_expect_success 'git rebase --skip' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_must_fail git rebase --onto A B &&
+	test_must_fail git rebase --skip &&
+	echo D > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_expect_success 'git rebase -m' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_must_fail git rebase -m --onto A B &&
+	echo C > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse C) $(git rev-parse HEAD^)
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_expect_success 'git rebase -m --skip' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_must_fail git rebase --onto A B &&
+	test_must_fail git rebase --skip &&
+	echo D > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+. "$TEST_DIRECTORY"/lib-rebase.sh
+
+set_fake_editor
+
+# Helper to work around the lack of one-shot exporting for
+# test_must_fail (as it is a shell function)
+test_fail_interactive_rebase () {
+	(
+		FAKE_LINES="$1" &&
+		shift &&
+		export FAKE_LINES &&
+		test_must_fail git rebase -i "$@"
+	)
+}
+
+test_expect_success 'git rebase -i (unchanged)' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_fail_interactive_rebase "1 2" --onto A B &&
+	echo C > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse C) $(git rev-parse HEAD^)
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_expect_success 'git rebase -i (skip)' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_fail_interactive_rebase "2" --onto A B &&
+	echo D > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_expect_success 'git rebase -i (squash)' '
+	git reset --hard D &&
+	clear_hook_input &&
+	test_fail_interactive_rebase "1 squash 2" --onto A B &&
+	echo C > foo &&
+	git add foo &&
+	git rebase --continue &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse C) $(git rev-parse HEAD)
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_expect_success 'git rebase -i (fixup without conflict)' '
+	git reset --hard D &&
+	clear_hook_input &&
+	FAKE_LINES="1 fixup 2" git rebase -i B &&
+	echo rebase >expected.args &&
+	cat >expected.data <<EOF &&
+$(git rev-parse C) $(git rev-parse HEAD)
+$(git rev-parse D) $(git rev-parse HEAD)
+EOF
+	verify_hook_input
+'
+
+test_done

t/t7501-commit.sh

@@ -425,4 +425,16 @@ test_expect_success 'amend using the message from a commit named with tag' '
 
 '
 
+test_expect_success 'amend can copy notes' '
+
+	git config notes.rewrite.amend true &&
+	git config notes.rewriteRef "refs/notes/*" &&
+	test_commit foo &&
+	git notes add -m"a note" &&
+	test_tick &&
+	git commit --amend -m"new foo" &&
+	test "$(git notes show)" = "a note"
+
+'
+
 test_done

t/test-lib.sh

@@ -54,6 +54,10 @@ unset GIT_OBJECT_DIRECTORY
 unset GIT_CEILING_DIRECTORIES
 unset SHA1_FILE_DIRECTORIES
 unset SHA1_FILE_DIRECTORY
+unset GIT_NOTES_REF
+unset GIT_NOTES_DISPLAY_REF
+unset GIT_NOTES_REWRITE_REF
+unset GIT_NOTES_REWRITE_MODE
 GIT_MERGE_VERBOSITY=5
 export GIT_MERGE_VERBOSITY
 export GIT_AUTHOR_EMAIL GIT_AUTHOR_NAME