Re: [PATCH] rebase -i: introduce the 'test' command

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Paul,

On Wed, 28 Nov 2018, Paul Morelle wrote:

> The 'exec' command can be used to run tests on a set of commits,
> interrupting on failing commits to let the user fix the tests.
> 
> However, the 'exec' line has been consumed, so it won't be ran again by
> 'git rebase --continue' is ran, even if the tests weren't fixed.
> 
> This commit introduces a new command 'test' equivalent to 'exec', except
> that it is automatically rescheduled in the todo list if it fails.
> 
> Signed-off-by: Paul Morelle <paul.morelle@gmail.com>

Would it not make more sense to add a command-line option (and a config
setting) to re-schedule failed `exec` commands? Like so:

-- snip --
diff --git a/builtin/rebase--interactive.c b/builtin/rebase--interactive.c
index a2ab68ed0632..a9ab009fdbca 100644
--- a/builtin/rebase--interactive.c
+++ b/builtin/rebase--interactive.c
@@ -192,6 +192,8 @@ int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
 		OPT_STRING(0, "onto-name", &onto_name, N_("onto-name"), N_("onto name")),
 		OPT_STRING(0, "cmd", &cmd, N_("cmd"), N_("the command to run")),
 		OPT_RERERE_AUTOUPDATE(&opts.allow_rerere_auto),
+		OPT_BOOL(0, "reschedule-failed-exec", &opts.reschedule_failed_exec,
+			 N_("automatically re-schedule any `exec` that fails")),
 		OPT_END()
 	};
 
diff --git a/builtin/rebase.c b/builtin/rebase.c
index 5b3e5baec8a0..700cbc4e150e 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -104,6 +104,7 @@ struct rebase_options {
 	int rebase_merges, rebase_cousins;
 	char *strategy, *strategy_opts;
 	struct strbuf git_format_patch_opt;
+	int reschedule_failed_exec;
 };
 
 static int is_interactive(struct rebase_options *opts)
@@ -415,6 +416,8 @@ static int run_specific_rebase(struct rebase_options *opts)
 			argv_array_push(&child.args, opts->gpg_sign_opt);
 		if (opts->signoff)
 			argv_array_push(&child.args, "--signoff");
+		if (opts->reschedule_failed_exec)
+			argv_array_push(&child.args, "--reschedule-failed-exec");
 
 		status = run_command(&child);
 		goto finished_rebase;
@@ -903,6 +906,9 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 				   "strategy")),
 		OPT_BOOL(0, "root", &options.root,
 			 N_("rebase all reachable commits up to the root(s)")),
+		OPT_BOOL(0, "reschedule-failed-exec",
+			 &options.reschedule_failed_exec,
+			 N_("automatically re-schedule any `exec` that fails")),
 		OPT_END(),
 	};
 	int i;
@@ -1195,6 +1201,9 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
 		break;
 	}
 
+	if (options.reschedule_failed_exec && !is_interactive(&options))
+		die(_("--reschedule-failed-exec requires an interactive rebase"));
+
 	if (options.git_am_opts.argc) {
 		/* all am options except -q are compatible only with --am */
 		for (i = options.git_am_opts.argc - 1; i >= 0; i--)
diff --git a/sequencer.c b/sequencer.c
index e1a4dd15f1a8..69bee63e116f 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -158,6 +158,7 @@ static GIT_PATH_FUNC(rebase_path_strategy, "rebase-merge/strategy")
 static GIT_PATH_FUNC(rebase_path_strategy_opts, "rebase-merge/strategy_opts")
 static GIT_PATH_FUNC(rebase_path_allow_rerere_autoupdate, "rebase-merge/allow_rerere_autoupdate")
 static GIT_PATH_FUNC(rebase_path_quiet, "rebase-merge/quiet")
+static GIT_PATH_FUNC(rebase_path_reschedule_failed_exec, "rebase-merge/reschedule-failed-exec")
 
 static int git_sequencer_config(const char *k, const char *v, void *cb)
 {
@@ -2362,6 +2363,9 @@ static int read_populate_opts(struct replay_opts *opts)
 			opts->signoff = 1;
 		}
 
+		if (file_exists(rebase_path_reschedule_failed_exec()))
+			opts->reschedule_failed_exec = 1;
+
 		read_strategy_opts(opts, &buf);
 		strbuf_release(&buf);
 
@@ -2443,6 +2447,8 @@ int write_basic_state(struct replay_opts *opts, const char *head_name,
 		write_file(rebase_path_gpg_sign_opt(), "-S%s\n", opts->gpg_sign);
 	if (opts->signoff)
 		write_file(rebase_path_signoff(), "--signoff\n");
+	if (opts->reschedule_failed_exec)
+		write_file(rebase_path_reschedule_failed_exec(), "%s", "");
 
 	return 0;
 }
@@ -3586,9 +3592,10 @@ static int pick_commits(struct todo_list *todo_list, struct replay_opts *opts)
 			*end_of_arg = saved;
 
 			/* Reread the todo file if it has changed. */
-			if (res)
-				; /* fall through */
-			else if (stat(get_todo_path(opts), &st))
+			if (res) {
+				if (opts->reschedule_failed_exec)
+					reschedule = 1;
+			} else if (stat(get_todo_path(opts), &st))
 				res = error_errno(_("could not stat '%s'"),
 						  get_todo_path(opts));
 			else if (match_stat_data(&todo_list->stat, &st)) {
diff --git a/sequencer.h b/sequencer.h
index 5071a73563f1..1f865dae2618 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -39,6 +39,7 @@ struct replay_opts {
 	int allow_empty_message;
 	int keep_redundant_commits;
 	int verbose;
+	int reschedule_failed_exec;
 
 	int mainline;
 
-- snap --

That would avoid your having to add a `--test` option accompanying the `--exec`
option (which is missing from your patch).

Ciao,
Johannes

> ---
>  Documentation/git-rebase.txt  |  9 ++++++---
>  rebase-interactive.c          |  1 +
>  sequencer.c                   | 23 +++++++++++++++--------
>  t/lib-rebase.sh               |  4 +++-
>  t/t3404-rebase-interactive.sh | 16 ++++++++++++++++
>  5 files changed, 41 insertions(+), 12 deletions(-)
> 
> diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
> index 80793bad8..c8f565637 100644
> --- a/Documentation/git-rebase.txt
> +++ b/Documentation/git-rebase.txt
> @@ -693,8 +693,8 @@ $ git rebase -i -p --onto Q O
>  Reordering and editing commits usually creates untested intermediate
>  steps.  You may want to check that your history editing did not break
>  anything by running a test, or at least recompiling at intermediate
> -points in history by using the "exec" command (shortcut "x").  You may
> -do so by creating a todo list like this one:
> +points in history by using the "exec" command (shortcut "x") or the
> +"test" command.  You may do so by creating a todo list like this one:
>   -------------------------------------------
>  pick deadbee Implement feature XXX
> @@ -702,7 +702,7 @@ fixup f1a5c00 Fix to feature XXX
>  exec make
>  pick c0ffeee The oneline of the next commit
>  edit deadbab The oneline of the commit after
> -exec cd subdir; make test
> +test cd subdir; make test
>  ...
>  -------------------------------------------
>  @@ -715,6 +715,9 @@ in `$SHELL`, or the default shell if `$SHELL` is
> not set), so you can
>  use shell features (like "cd", ">", ";" ...). The command is run from
>  the root of the working tree.
>  +The "test" command does the same, but will remain in the todo list as
> +the next command, until it succeeds.
> +
>  ----------------------------------
>  $ git rebase -i --exec "make test"
>  ----------------------------------
> diff --git a/rebase-interactive.c b/rebase-interactive.c
> index 78f3263fc..4a408661d 100644
> --- a/rebase-interactive.c
> +++ b/rebase-interactive.c
> @@ -14,6 +14,7 @@ void append_todo_help(unsigned edit_todo, unsigned
> keep_empty,
>  "s, squash <commit> = use commit, but meld into previous commit\n"
>  "f, fixup <commit> = like \"squash\", but discard this commit's log
> message\n"
>  "x, exec <command> = run command (the rest of the line) using shell\n"
> +"   test <command> = same as exec command, but keep it in TODO if it
> fails\n"
>  "b, break = stop here (continue rebase later with 'git rebase
> --continue')\n"
>  "d, drop <commit> = remove commit\n"
>  "l, label <label> = label current HEAD with a name\n"
> diff --git a/sequencer.c b/sequencer.c
> index e1a4dd15f..c3dde6910 100644
> --- a/sequencer.c
> +++ b/sequencer.c
> @@ -1508,6 +1508,7 @@ enum todo_command {
>  	TODO_SQUASH,
>  	/* commands that do something else than handling a single commit */
>  	TODO_EXEC,
> +	TODO_TEST,
>  	TODO_BREAK,
>  	TODO_LABEL,
>  	TODO_RESET,
> @@ -1530,6 +1531,7 @@ static struct {
>  	{ 'f', "fixup" },
>  	{ 's', "squash" },
>  	{ 'x', "exec" },
> +	{ 0,   "test" },
>  	{ 'b', "break" },
>  	{ 'l', "label" },
>  	{ 't', "reset" },
> @@ -2072,7 +2074,7 @@ static int parse_insn_line(struct todo_item *item,
> const char *bol, char *eol)
>  			     command_to_string(item->command));
>   	if (item->command == TODO_EXEC || item->command == TODO_LABEL ||
> -	    item->command == TODO_RESET) {
> +	    item->command == TODO_RESET || item->command == TODO_TEST) {
>  		item->commit = NULL;
>  		item->arg = bol;
>  		item->arg_len = (int)(eol - bol);
> @@ -3576,7 +3578,7 @@ static int pick_commits(struct todo_list
> *todo_list, struct replay_opts *opts)
>  						item->arg, item->arg_len, opts,
>  						res, to_amend);
>  			}
> -		} else if (item->command == TODO_EXEC) {
> +		} else if (item->command == TODO_EXEC || item->command == TODO_TEST) {
>  			char *end_of_arg = (char *)(item->arg + item->arg_len);
>  			int saved = *end_of_arg;
>  			struct stat st;
> @@ -3586,9 +3588,12 @@ static int pick_commits(struct todo_list
> *todo_list, struct replay_opts *opts)
>  			*end_of_arg = saved;
>   			/* Reread the todo file if it has changed. */
> -			if (res)
> +			if (res) {
>  				; /* fall through */
> -			else if (stat(get_todo_path(opts), &st))
> +				if (item->command == TODO_TEST) {
> +					reschedule = 1;
> +				}
> +			} else if (stat(get_todo_path(opts), &st))
>  				res = error_errno(_("could not stat '%s'"),
>  						  get_todo_path(opts));
>  			else if (match_stat_data(&todo_list->stat, &st)) {
> @@ -3622,10 +3627,12 @@ static int pick_commits(struct todo_list
> *todo_list, struct replay_opts *opts)
>  			return error(_("unknown command %d"), item->command);
>   		if (reschedule) {
> -			advise(_(rescheduled_advice),
> -			       get_item_line_length(todo_list,
> -						    todo_list->current),
> -			       get_item_line(todo_list, todo_list->current));
> +			if (item->command != TODO_TEST) {
> +				advise(_(rescheduled_advice),
> +				       get_item_line_length(todo_list,
> +							    todo_list->current),
> +				       get_item_line(todo_list, todo_list->current));
> +			}
>  			todo_list->current--;
>  			if (save_todo(todo_list, opts))
>  				return -1;
> diff --git a/t/lib-rebase.sh b/t/lib-rebase.sh
> index 7ea30e500..7d36f00bd 100644
> --- a/t/lib-rebase.sh
> +++ b/t/lib-rebase.sh
> @@ -19,6 +19,8 @@
>  #
>  #   "exec_cmd_with_args" -- add an "exec cmd with args" line.
>  #
> +#   "test_cmd_with_args" -- add a "test cmd with args" line.
> +#
>  #   "#" -- Add a comment line.
>  #
>  #   ">" -- Add a blank line.
> @@ -49,7 +51,7 @@ set_fake_editor () {
>  		case $line in
>  		pick|p|squash|s|fixup|f|edit|e|reword|r|drop|d)
>  			action="$line";;
> -		exec_*|x_*|break|b)
> +		exec_*|x_*|break|b|test_*)
>  			echo "$line" | sed 's/_/ /g' >> "$1";;
>  		"#")
>  			echo '# comment' >> "$1";;
> diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
> index 7a440e08d..14c60b14d 100755
> --- a/t/t3404-rebase-interactive.sh
> +++ b/t/t3404-rebase-interactive.sh
> @@ -1453,4 +1453,20 @@ test_expect_success 'valid author header when
> author contains single quote' '
>  	test_cmp expected actual
>  '
>  +test_expect_success 'rebase -i keeps test until it passes' '
> +	git checkout master &&
> +	(
> +	set_fake_editor &&
> +	FAKE_LINES="1 test_false 2 3 4 5" &&
> +	export FAKE_LINES &&
> +	test_must_fail git rebase -i A &&
> +	test_cmp_rev B HEAD &&
> +	test_must_fail git rebase --continue &&
> +	test_cmp_rev B HEAD &&
> +	FAKE_LINES="test_true 2 3 4" git rebase --edit-todo &&
> +	git rebase --continue
> +	) &&
> +	test_cmp_rev master HEAD
> +'
> +
>  test_done
> -- 
> 2.19.1
> 
>