Merge branch 'pw/rebase-i-more-options' into pu

"git rebase -i" learns a bit more options.

Not quite.
cf. <nycvar.QRO.7.76.6.2005290437350.56@tvgsbejvaqbjf.bet>

* pw/rebase-i-more-options:
  rebase: add --reset-author-date
  rebase -i: support --ignore-date
  sequencer: rename amend_author to author_to_free
  rebase -i: support --committer-date-is-author-date
  rebase -i: add --ignore-whitespace flag

Documentation/git-rebase.txt

@@ -459,17 +459,38 @@ with `--keep-base` in order to drop those commits from your branch.
 See also INCOMPATIBLE OPTIONS below.
 
 --ignore-whitespace::
+	Ignore whitespace differences when trying to reconcile
+differences. Currently, each backend implements an approximation of
+this behavior:
++
+apply backend: When applying a patch, ignore changes in whitespace in
+context lines. Unfortunately, this means that if the "old" lines being
+replaced by the patch differ only in whitespace from the existing
+file, you will get a merge conflict instead of a successful patch
+application.
++
+merge backend: Treat lines with only whitespace changes as unchanged
+when merging. Unfortunately, this means that any patch hunks that were
+intended to modify whitespace and nothing else will be dropped, even
+if the other side had no changes that conflicted.
+
 --whitespace=<option>::
-	These flags are passed to the 'git apply' program
+	This flag is passed to the 'git apply' program
 	(see linkgit:git-apply[1]) that applies the patch.
 	Implies --apply.
 +
 See also INCOMPATIBLE OPTIONS below.
 
 --committer-date-is-author-date::
+	Instead of using the current time as the committer date, use
+	the author date of the commit being rebased as the committer
+	date. This option implies --force-rebase.
+
 --ignore-date::
-	These flags are passed to 'git am' to easily change the dates
+--reset-author-date::
-	of the rebased commits (see linkgit:git-am[1]).
+	Instead of using the author date of the original commit, use
+	the current time as the	author date of the rebased commit.  This
+	option implies `--force-rebase`.
 +
 See also INCOMPATIBLE OPTIONS below.
 
@@ -607,9 +628,6 @@ INCOMPATIBLE OPTIONS
 The following options:
 
  * --apply
- * --committer-date-is-author-date
- * --ignore-date
- * --ignore-whitespace
  * --whitespace
  * -C
 
@@ -636,6 +654,9 @@ In addition, the following pairs of options are incompatible:
  * --preserve-merges and --signoff
  * --preserve-merges and --rebase-merges
  * --preserve-merges and --empty=
+ * --preserve-merges and --ignore-whitespace
+ * --preserve-merges and --committer-date-is-author-date
+ * --preserve-merges and --ignore-date
  * --keep-base and --onto
  * --keep-base and --root
  * --fork-point and --root

builtin/rebase.c

@@ -90,8 +90,11 @@ struct rebase_options {
 	int allow_rerere_autoupdate;
 	int keep_empty;
 	int autosquash;
+	int ignore_whitespace;
 	char *gpg_sign_opt;
 	int autostash;
+	int committer_date_is_author_date;
+	int ignore_date;
 	char *cmd;
 	int allow_empty_message;
 	int rebase_merges, rebase_cousins;
@@ -114,6 +117,7 @@ struct rebase_options {
 
 static struct replay_opts get_replay_opts(const struct rebase_options *opts)
 {
+	struct strbuf strategy_buf = STRBUF_INIT;
 	struct replay_opts replay = REPLAY_OPTS_INIT;
 
 	replay.action = REPLAY_INTERACTIVE_REBASE;
@@ -130,16 +134,25 @@ static struct replay_opts get_replay_opts(const struct rebase_options *opts)
 	replay.quiet = !(opts->flags & REBASE_NO_QUIET);
 	replay.verbose = opts->flags & REBASE_VERBOSE;
 	replay.reschedule_failed_exec = opts->reschedule_failed_exec;
+	replay.committer_date_is_author_date =
+					opts->committer_date_is_author_date;
+	replay.ignore_date = opts->ignore_date;
 	replay.gpg_sign = xstrdup_or_null(opts->gpg_sign_opt);
 	replay.strategy = opts->strategy;
+
 	if (opts->strategy_opts)
-		parse_strategy_opts(&replay, opts->strategy_opts);
+		strbuf_addstr(&strategy_buf, opts->strategy_opts);
+	if (opts->ignore_whitespace)
+		strbuf_addstr(&strategy_buf, " --ignore-space-change");
+	if (strategy_buf.len)
+		parse_strategy_opts(&replay, strategy_buf.buf);
 
 	if (opts->squash_onto) {
 		oidcpy(&replay.squash_onto, opts->squash_onto);
 		replay.have_squash_onto = 1;
 	}
 
+	strbuf_release(&strategy_buf);
 	return replay;
 }
 
@@ -546,6 +559,8 @@ int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
 	argc = parse_options(argc, argv, prefix, options,
 			builtin_rebase_interactive_usage, PARSE_OPT_KEEP_ARGV0);
 
+	opts.strategy_opts = xstrdup_or_null(opts.strategy_opts);
+
 	if (!is_null_oid(&squash_onto))
 		opts.squash_onto = &squash_onto;
 
@@ -813,6 +828,12 @@ static int run_am(struct rebase_options *opts)
 	am.git_cmd = 1;
 	argv_array_push(&am.args, "am");
 
+	if (opts->ignore_whitespace)
+		argv_array_push(&am.args, "--ignore-whitespace");
+	if (opts->committer_date_is_author_date)
+		argv_array_push(&opts->git_am_opts, "--committer-date-is-author-date");
+	if (opts->ignore_date)
+		argv_array_push(&opts->git_am_opts, "--ignore-date");
 	if (opts->action && !strcmp("continue", opts->action)) {
 		argv_array_push(&am.args, "--resolved");
 		argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
@@ -1318,16 +1339,17 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 			PARSE_OPT_NOARG, NULL, REBASE_DIFFSTAT },
 		OPT_BOOL(0, "signoff", &options.signoff,
 			 N_("add a Signed-off-by: line to each commit")),
-		OPT_PASSTHRU_ARGV(0, "ignore-whitespace", &options.git_am_opts,
+		OPT_BOOL(0, "committer-date-is-author-date",
-				  NULL, N_("passed to 'git am'"),
+			 &options.committer_date_is_author_date,
-				  PARSE_OPT_NOARG),
+			 N_("make committer date match author date")),
-		OPT_PASSTHRU_ARGV(0, "committer-date-is-author-date",
+		OPT_BOOL(0, "reset-author-date", &options.ignore_date,
-				  &options.git_am_opts, NULL,
+			 N_("ignore author date and use current date")),
-				  N_("passed to 'git am'"), PARSE_OPT_NOARG),
+		OPT_HIDDEN_BOOL(0, "ignore-date", &options.ignore_date,
-		OPT_PASSTHRU_ARGV(0, "ignore-date", &options.git_am_opts, NULL,
+				N_("synonym of --reset-author-date")),
-				  N_("passed to 'git am'"), PARSE_OPT_NOARG),
 		OPT_PASSTHRU_ARGV('C', NULL, &options.git_am_opts, N_("n"),
 				  N_("passed to 'git apply'"), 0),
+		OPT_BOOL(0, "ignore-whitespace", &options.ignore_whitespace,
+			 N_("ignore changes in whitespace")),
 		OPT_PASSTHRU_ARGV(0, "whitespace", &options.git_am_opts,
 				  N_("action"), N_("passed to 'git apply'"), 0),
 		OPT_BIT('f', "force-rebase", &options.flags,
@@ -1624,12 +1646,12 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 	    options.autosquash) {
 		allow_preemptive_ff = 0;
 	}
+	if (options.committer_date_is_author_date || options.ignore_date)
+		options.flags |= REBASE_FORCE;
 
 	for (i = 0; i < options.git_am_opts.argc; i++) {
 		const char *option = options.git_am_opts.argv[i], *p;
-		if (!strcmp(option, "--committer-date-is-author-date") ||
+		if (!strcmp(option, "--whitespace=fix") ||
-		    !strcmp(option, "--ignore-date") ||
-		    !strcmp(option, "--whitespace=fix") ||
 		    !strcmp(option, "--whitespace=strip"))
 			allow_preemptive_ff = 0;
 		else if (skip_prefix(option, "-C", &p)) {

sequencer.c

@@ -150,6 +150,8 @@ static GIT_PATH_FUNC(rebase_path_refs_to_delete, "rebase-merge/refs-to-delete")
  * command-line.
  */
 static GIT_PATH_FUNC(rebase_path_gpg_sign_opt, "rebase-merge/gpg_sign_opt")
+static GIT_PATH_FUNC(rebase_path_cdate_is_adate, "rebase-merge/cdate_is_adate")
+static GIT_PATH_FUNC(rebase_path_ignore_date, "rebase-merge/ignore_date")
 static GIT_PATH_FUNC(rebase_path_orig_head, "rebase-merge/orig-head")
 static GIT_PATH_FUNC(rebase_path_verbose, "rebase-merge/verbose")
 static GIT_PATH_FUNC(rebase_path_quiet, "rebase-merge/quiet")
@@ -863,6 +865,40 @@ static char *get_author(const char *message)
 	return NULL;
 }
 
+static const char *author_date_from_env_array(const struct argv_array *env)
+{
+	int i;
+	const char *date;
+
+	for (i = 0; i < env->argc; i++)
+		if (skip_prefix(env->argv[i],
+				"GIT_AUTHOR_DATE=", &date))
+			return date;
+	/*
+	 * If GIT_AUTHOR_DATE is missing we should have already errored out when
+	 * reading the script
+	 */
+	BUG("GIT_AUTHOR_DATE missing from author script");
+}
+
+/* Construct a free()able author string with current time as the author date */
+static char *ignore_author_date(const char *author)
+{
+	int len = strlen(author);
+	struct ident_split ident;
+	struct strbuf new_author = STRBUF_INIT;
+
+	if (split_ident_line(&ident, author, len) < 0) {
+		error(_("malformed ident line '%s'"), author);
+		return NULL;
+	}
+
+	len = ident.mail_end - ident.name_begin + 1;
+	strbuf_addf(&new_author, "%.*s ", len, ident.name_begin);
+	datestamp(&new_author);
+	return strbuf_detach(&new_author, NULL);
+}
+
 static const char staged_changes_advice[] =
 N_("you have staged changes in your working tree\n"
 "If these changes are meant to be squashed into the previous commit, run:\n"
@@ -929,6 +965,14 @@ static int run_git_commit(struct repository *r,
 			     gpg_opt, gpg_opt);
 	}
 
+	if (opts->committer_date_is_author_date)
+		argv_array_pushf(&cmd.env_array, "GIT_COMMITTER_DATE=%s",
+				 opts->ignore_date ?
+				 "" :
+				 author_date_from_env_array(&cmd.env_array));
+	if (opts->ignore_date)
+		argv_array_push(&cmd.env_array, "GIT_AUTHOR_DATE=");
+
 	argv_array_push(&cmd.args, "commit");
 
 	if (!(flags & VERIFY_MSG))
@@ -1307,7 +1351,7 @@ static int try_to_commit(struct repository *r,
 	struct commit_extra_header *extra = NULL;
 	struct strbuf err = STRBUF_INIT;
 	struct strbuf commit_msg = STRBUF_INIT;
-	char *amend_author = NULL;
+	char *author_to_free = NULL;
 	const char *hook_commit = NULL;
 	enum commit_msg_cleanup_mode cleanup;
 	int res = 0;
@@ -1329,7 +1373,7 @@ static int try_to_commit(struct repository *r,
 			strbuf_addstr(msg, orig_message);
 			hook_commit = "HEAD";
 		}
-		author = amend_author = get_author(message);
+		author = author_to_free = get_author(message);
 		unuse_commit_buffer(current_head, message);
 		if (!author) {
 			res = error(_("unable to parse commit author"));
@@ -1342,6 +1386,31 @@ static int try_to_commit(struct repository *r,
 		commit_list_insert(current_head, &parents);
 	}
 
+	if (opts->committer_date_is_author_date) {
+		int len = strlen(author);
+		struct ident_split ident;
+		struct strbuf date = STRBUF_INIT;
+
+		if (split_ident_line(&ident, author, len) < 0) {
+			res = error(_("malformed ident line '%s'"), author);
+			goto out;
+		}
+		if (!ident.date_begin) {
+			res = error(_("corrupted author without date information"));
+			goto out;
+		}
+
+		strbuf_addf(&date, "@%.*s %.*s",
+			    (int)(ident.date_end - ident.date_begin), ident.date_begin,
+			    (int)(ident.tz_end - ident.tz_begin), ident.tz_begin);
+		res = setenv("GIT_COMMITTER_DATE",
+			     opts->ignore_date ? "" : date.buf, 1);
+		strbuf_release(&date);
+
+		if (res)
+			goto out;
+	}
+
 	if (write_index_as_tree(&tree, r->index, r->index_file, 0, NULL)) {
 		res = error(_("git write-tree failed to write a tree"));
 		goto out;
@@ -1401,6 +1470,16 @@ static int try_to_commit(struct repository *r,
 
 	reset_ident_date();
 
+	if (opts->ignore_date) {
+		author = ignore_author_date(author);
+		if (!author) {
+			res = -1;
+			goto out;
+		}
+		free(author_to_free);
+		author_to_free = (char *)author;
+	}
+
 	if (commit_tree_extended(msg->buf, msg->len, &tree, parents,
 				 oid, author, opts->gpg_sign, extra)) {
 		res = error(_("failed to write commit object"));
@@ -1421,7 +1500,7 @@ out:
 	free_commit_extra_headers(extra);
 	strbuf_release(&err);
 	strbuf_release(&commit_msg);
-	free(amend_author);
+	free(author_to_free);
 
 	return res;
 }
@@ -2528,6 +2607,16 @@ static int read_populate_opts(struct replay_opts *opts)
 			opts->signoff = 1;
 		}
 
+		if (file_exists(rebase_path_cdate_is_adate())) {
+			opts->allow_ff = 0;
+			opts->committer_date_is_author_date = 1;
+		}
+
+		if (file_exists(rebase_path_ignore_date())) {
+			opts->allow_ff = 0;
+			opts->ignore_date = 1;
+		}
+
 		if (file_exists(rebase_path_reschedule_failed_exec()))
 			opts->reschedule_failed_exec = 1;
 
@@ -2623,6 +2712,10 @@ int write_basic_state(struct replay_opts *opts, const char *head_name,
 		write_file(rebase_path_drop_redundant_commits(), "%s", "");
 	if (opts->keep_redundant_commits)
 		write_file(rebase_path_keep_redundant_commits(), "%s", "");
+	if (opts->committer_date_is_author_date)
+		write_file(rebase_path_cdate_is_adate(), "%s", "");
+	if (opts->ignore_date)
+		write_file(rebase_path_ignore_date(), "%s", "");
 	if (opts->reschedule_failed_exec)
 		write_file(rebase_path_reschedule_failed_exec(), "%s", "");
 
@@ -3543,6 +3636,14 @@ static int do_merge(struct repository *r,
 			goto leave_merge;
 		}
 
+		if (opts->committer_date_is_author_date)
+			argv_array_pushf(&cmd.env_array, "GIT_COMMITTER_DATE=%s",
+					 opts->ignore_date ?
+					 "" :
+					 author_date_from_env_array(&cmd.env_array));
+		if (opts->ignore_date)
+			argv_array_push(&cmd.env_array, "GIT_AUTHOR_DATE=");
+
 		cmd.git_cmd = 1;
 		argv_array_push(&cmd.args, "merge");
 		argv_array_push(&cmd.args, "-s");
@@ -3906,7 +4007,9 @@ static int pick_commits(struct repository *r,
 	prev_reflog_action = xstrdup(getenv(GIT_REFLOG_ACTION));
 	if (opts->allow_ff)
 		assert(!(opts->signoff || opts->no_commit ||
-				opts->record_origin || opts->edit));
+				opts->record_origin || opts->edit ||
+				opts->committer_date_is_author_date ||
+				opts->ignore_date));
 	if (read_and_refresh_cache(r, opts))
 		return -1;
 

sequencer.h

@@ -45,6 +45,8 @@ struct replay_opts {
 	int verbose;
 	int quiet;
 	int reschedule_failed_exec;
+	int committer_date_is_author_date;
+	int ignore_date;
 
 	int mainline;
 

t/t3422-rebase-incompatible-options.sh

@@ -61,8 +61,6 @@ test_rebase_am_only () {
 }
 
 test_rebase_am_only --whitespace=fix
-test_rebase_am_only --ignore-whitespace
-test_rebase_am_only --committer-date-is-author-date
 test_rebase_am_only -C4
 
 test_expect_success REBASE_P '--preserve-merges incompatible with --signoff' '

t/t3436-rebase-more-options.sh

@@ -0,0 +1,209 @@
+#!/bin/sh
+#
+# Copyright (c) 2019 Rohit Ashiwal
+#
+
+test_description='tests to ensure compatibility between am and interactive backends'
+
+. ./test-lib.sh
+
+. "$TEST_DIRECTORY"/lib-rebase.sh
+
+GIT_AUTHOR_DATE="1999-04-02T08:03:20+05:30"
+export GIT_AUTHOR_DATE
+
+# This is a special case in which both am and interactive backends
+# provide the same output. It was done intentionally because
+# both the backends fall short of optimal behaviour.
+test_expect_success 'setup' '
+	git checkout -b topic &&
+	q_to_tab >file <<-\EOF &&
+	line 1
+	Qline 2
+	line 3
+	EOF
+	git add file &&
+	git commit -m "add file" &&
+	cat >file <<-\EOF &&
+	line 1
+	new line 2
+	line 3
+	EOF
+	git commit -am "update file" &&
+	git tag side &&
+	test_commit commit1 foo foo1 &&
+	test_commit commit2 foo foo2 &&
+	test_commit commit3 foo foo3 &&
+
+	git checkout --orphan master &&
+	git rm --cached foo &&
+	rm foo &&
+	sed -e "s/^|//" >file <<-\EOF &&
+	|line 1
+	|        line 2
+	|line 3
+	EOF
+	git add file &&
+	git commit -m "add file" &&
+	git tag main
+'
+
+test_expect_success '--ignore-whitespace works with apply backend' '
+	cat >expect <<-\EOF &&
+	line 1
+	new line 2
+	line 3
+	EOF
+	test_must_fail git rebase --apply main side &&
+	git rebase --abort &&
+	git rebase --apply --ignore-whitespace main side &&
+	test_cmp expect file
+'
+
+test_expect_success '--ignore-whitespace works with merge backend' '
+	cat >expect <<-\EOF &&
+	line 1
+	new line 2
+	line 3
+	EOF
+	test_must_fail git rebase --merge main side &&
+	git rebase --abort &&
+	git rebase --merge --ignore-whitespace main side &&
+	test_cmp expect file
+'
+
+test_expect_success '--ignore-whitespace is remembered when continuing' '
+	cat >expect <<-\EOF &&
+	line 1
+	new line 2
+	line 3
+	EOF
+	(
+		set_fake_editor &&
+		FAKE_LINES="break 1" git rebase -i --ignore-whitespace main side
+	) &&
+	git rebase --continue &&
+	test_cmp expect file
+'
+
+test_expect_success '--committer-date-is-author-date works with apply backend' '
+	GIT_AUTHOR_DATE="@1234 +0300" git commit --amend --reset-author &&
+	git rebase --apply --committer-date-is-author-date HEAD^ &&
+	git log -1 --pretty=%ai >authortime &&
+	git log -1 --pretty=%ci >committertime &&
+	test_cmp authortime committertime
+'
+
+test_expect_success '--committer-date-is-author-date works with merge backend' '
+	GIT_AUTHOR_DATE="@1234 +0300" git commit --amend --reset-author &&
+	git rebase -m --committer-date-is-author-date HEAD^ &&
+	git log -1 --pretty=%ai >authortime &&
+	git log -1 --pretty=%ci >committertime &&
+	test_cmp authortime committertime
+'
+
+test_expect_success '--committer-date-is-author-date works with rebase -r' '
+	git checkout side &&
+	GIT_AUTHOR_DATE="@1234 +0300" git merge --no-ff commit3 &&
+	git rebase -r --root --committer-date-is-author-date &&
+	git log --pretty=%ai >authortime &&
+	git log --pretty=%ci >committertime &&
+	test_cmp authortime committertime
+'
+
+test_expect_success '--committer-date-is-author-date works when forking merge' '
+	git checkout side &&
+	GIT_AUTHOR_DATE="@1234 +0300" git merge --no-ff commit3 &&
+	git rebase -r --root --strategy=resolve --committer-date-is-author-date &&
+	git log --pretty=%ai >authortime &&
+	git log --pretty=%ci >committertime &&
+	test_cmp authortime committertime
+
+'
+
+test_expect_success '--committer-date-is-author-date works when committing conflict resolution' '
+	git checkout commit2 &&
+	GIT_AUTHOR_DATE="@1980 +0000" git commit --amend --only --reset-author &&
+	git log -1 --format=%at HEAD >expect &&
+	test_must_fail git rebase -m --committer-date-is-author-date \
+		--onto HEAD^^ HEAD^ &&
+	echo resolved > foo &&
+	git add foo &&
+	git rebase --continue &&
+	git log -1 --format=%ct HEAD >actual &&
+	test_cmp expect actual
+'
+
+# Checking for +0000 in author time is enough since default
+# timezone is UTC, but the timezone used while committing
+# sets to +0530.
+test_expect_success '--reset-author-date works with apply backend' '
+	git commit --amend --date="$GIT_AUTHOR_DATE" &&
+	git rebase --apply --reset-author-date HEAD^ &&
+	git log -1 --pretty=%ai >authortime &&
+	grep "+0000" authortime
+'
+
+test_expect_success '--reset-author-date works with merge backend' '
+	git commit --amend --date="$GIT_AUTHOR_DATE" &&
+	git rebase --reset-author-date -m HEAD^ &&
+	git log -1 --pretty=%ai >authortime &&
+	grep "+0000" authortime
+'
+
+test_expect_success '--reset-author-date works after conflict resolution' '
+	test_must_fail git rebase --reset-author-date -m \
+		--onto commit2^^ commit2^ commit2 &&
+	echo resolved >foo &&
+	git add foo &&
+	git rebase --continue &&
+	git log -1 --pretty=%ai >authortime &&
+	grep +0000 authortime
+'
+
+test_expect_success '--reset-author-date works with rebase -r' '
+	git checkout side &&
+	git merge --no-ff commit3 &&
+	git rebase -r --root --reset-author-date &&
+	git log --pretty=%ai >authortime &&
+	! grep -v "+0000" authortime
+'
+
+test_expect_success '--reset-author-date with --committer-date-is-author-date works' '
+	test_must_fail git rebase -m --committer-date-is-author-date \
+		--reset-author-date --onto commit2^^ commit2^ commit3 &&
+	git checkout --theirs foo &&
+	git add foo &&
+	git rebase --continue &&
+	git log -2 --pretty=%ai >authortime &&
+	git log -2 --pretty=%ci >committertime &&
+	test_cmp authortime committertime &&
+	! grep -v "+0000" authortime
+'
+
+test_expect_success '--reset-author-date --committer-date-is-author-date works when forking merge' '
+	GIT_SEQUENCE_EDITOR="echo \"merge -C $(git rev-parse HEAD) commit3\">" \
+		git rebase -i --strategy=resolve --reset-author-date \
+		--committer-date-is-author-date side side &&
+	git log -1 --pretty=%ai >authortime &&
+	git log -1 --pretty=%ci >committertime &&
+	test_cmp authortime committertime &&
+	grep "+0000" authortime
+ '
+
+test_expect_success '--ignore-date is an alias for --reset-author-date' '
+	git commit --amend --date="$GIT_AUTHOR_DATE" &&
+	git rebase --apply --ignore-date HEAD^ &&
+	git commit --allow-empty -m empty --date="$GIT_AUTHOR_DATE" &&
+	git rebase -m --ignore-date HEAD^ &&
+	git log -2 --pretty=%ai >authortime &&
+	grep "+0000" authortime >output &&
+	test_line_count = 2 output
+'
+
+# This must be the last test in this file
+test_expect_success '$EDITOR and friends are unchanged' '
+	test_editor_unchanged
+'
+
+test_done