git-commit-vandalism/builtin/rebase--helper.c

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rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
#include "builtin.h"
#include "cache.h"
#include "config.h"
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
#include "parse-options.h"
#include "sequencer.h"
static const char * const builtin_rebase_helper_usage[] = {
N_("git rebase--helper [<options>]"),
NULL
};
int cmd_rebase__helper(int argc, const char **argv, const char *prefix)
{
struct replay_opts opts = REPLAY_OPTS_INIT;
unsigned flags = 0, keep_empty = 0, rebase_merges = 0;
rebase -i: introduce --rebase-merges=[no-]rebase-cousins When running `git rebase --rebase-merges` non-interactively with an ancestor of HEAD as <upstream> (or leaving the todo list unmodified), we would ideally recreate the exact same commits as before the rebase. However, if there are commits in the commit range <upstream>.. that do not have <upstream> as direct ancestor (i.e. if `git log <upstream>..` would show commits that are omitted by `git log --ancestry-path <upstream>..`), this is currently not the case: we would turn them into commits that have <upstream> as direct ancestor. Let's illustrate that with a diagram: C / \ A - B - E - F \ / D Currently, after running `git rebase -i --rebase-merges B`, the new branch structure would be (pay particular attention to the commit `D`): --- C' -- / \ A - B ------ E' - F' \ / D' This is not really preserving the branch topology from before! The reason is that the commit `D` does not have `B` as ancestor, and therefore it gets rebased onto `B`. This is unintuitive behavior. Even worse, when recreating branch structure, most use cases would appear to want cousins *not* to be rebased onto the new base commit. For example, Git for Windows (the heaviest user of the Git garden shears, which served as the blueprint for --rebase-merges) frequently merges branches from `next` early, and these branches certainly do *not* want to be rebased. In the example above, the desired outcome would look like this: --- C' -- / \ A - B ------ E' - F' \ / -- D' -- Let's introduce the term "cousins" for such commits ("D" in the example), and let's not rebase them by default. For hypothetical use cases where cousins *do* need to be rebased, `git rebase --rebase=merges=rebase-cousins` needs to be used. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-25 14:29:40 +02:00
int abbreviate_commands = 0, rebase_cousins = -1;
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
enum {
CONTINUE = 1, ABORT, MAKE_SCRIPT, SHORTEN_OIDS, EXPAND_OIDS,
CHECK_TODO_LIST, SKIP_UNNECESSARY_PICKS, REARRANGE_SQUASH,
ADD_EXEC
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
} command = 0;
struct option options[] = {
OPT_BOOL(0, "ff", &opts.allow_ff, N_("allow fast-forward")),
OPT_BOOL(0, "keep-empty", &keep_empty, N_("keep empty commits")),
OPT_BOOL(0, "allow-empty-message", &opts.allow_empty_message,
N_("allow commits with empty messages")),
OPT_BOOL(0, "rebase-merges", &rebase_merges, N_("rebase merge commits")),
rebase -i: introduce --rebase-merges=[no-]rebase-cousins When running `git rebase --rebase-merges` non-interactively with an ancestor of HEAD as <upstream> (or leaving the todo list unmodified), we would ideally recreate the exact same commits as before the rebase. However, if there are commits in the commit range <upstream>.. that do not have <upstream> as direct ancestor (i.e. if `git log <upstream>..` would show commits that are omitted by `git log --ancestry-path <upstream>..`), this is currently not the case: we would turn them into commits that have <upstream> as direct ancestor. Let's illustrate that with a diagram: C / \ A - B - E - F \ / D Currently, after running `git rebase -i --rebase-merges B`, the new branch structure would be (pay particular attention to the commit `D`): --- C' -- / \ A - B ------ E' - F' \ / D' This is not really preserving the branch topology from before! The reason is that the commit `D` does not have `B` as ancestor, and therefore it gets rebased onto `B`. This is unintuitive behavior. Even worse, when recreating branch structure, most use cases would appear to want cousins *not* to be rebased onto the new base commit. For example, Git for Windows (the heaviest user of the Git garden shears, which served as the blueprint for --rebase-merges) frequently merges branches from `next` early, and these branches certainly do *not* want to be rebased. In the example above, the desired outcome would look like this: --- C' -- / \ A - B ------ E' - F' \ / -- D' -- Let's introduce the term "cousins" for such commits ("D" in the example), and let's not rebase them by default. For hypothetical use cases where cousins *do* need to be rebased, `git rebase --rebase=merges=rebase-cousins` needs to be used. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-25 14:29:40 +02:00
OPT_BOOL(0, "rebase-cousins", &rebase_cousins,
N_("keep original branch points of cousins")),
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
OPT_CMDMODE(0, "continue", &command, N_("continue rebase"),
CONTINUE),
OPT_CMDMODE(0, "abort", &command, N_("abort rebase"),
ABORT),
OPT_CMDMODE(0, "make-script", &command,
N_("make rebase script"), MAKE_SCRIPT),
OPT_CMDMODE(0, "shorten-ids", &command,
N_("shorten commit ids in the todo list"), SHORTEN_OIDS),
OPT_CMDMODE(0, "expand-ids", &command,
N_("expand commit ids in the todo list"), EXPAND_OIDS),
OPT_CMDMODE(0, "check-todo-list", &command,
N_("check the todo list"), CHECK_TODO_LIST),
OPT_CMDMODE(0, "skip-unnecessary-picks", &command,
N_("skip unnecessary picks"), SKIP_UNNECESSARY_PICKS),
OPT_CMDMODE(0, "rearrange-squash", &command,
N_("rearrange fixup/squash lines"), REARRANGE_SQUASH),
OPT_CMDMODE(0, "add-exec-commands", &command,
N_("insert exec commands in todo list"), ADD_EXEC),
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
OPT_END()
};
sequencer_init_config(&opts);
git_config_get_bool("rebase.abbreviatecommands", &abbreviate_commands);
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
opts.action = REPLAY_INTERACTIVE_REBASE;
opts.allow_ff = 1;
opts.allow_empty = 1;
argc = parse_options(argc, argv, NULL, options,
builtin_rebase_helper_usage, PARSE_OPT_KEEP_ARGV0);
flags |= keep_empty ? TODO_LIST_KEEP_EMPTY : 0;
flags |= abbreviate_commands ? TODO_LIST_ABBREVIATE_CMDS : 0;
flags |= rebase_merges ? TODO_LIST_REBASE_MERGES : 0;
rebase -i: introduce --rebase-merges=[no-]rebase-cousins When running `git rebase --rebase-merges` non-interactively with an ancestor of HEAD as <upstream> (or leaving the todo list unmodified), we would ideally recreate the exact same commits as before the rebase. However, if there are commits in the commit range <upstream>.. that do not have <upstream> as direct ancestor (i.e. if `git log <upstream>..` would show commits that are omitted by `git log --ancestry-path <upstream>..`), this is currently not the case: we would turn them into commits that have <upstream> as direct ancestor. Let's illustrate that with a diagram: C / \ A - B - E - F \ / D Currently, after running `git rebase -i --rebase-merges B`, the new branch structure would be (pay particular attention to the commit `D`): --- C' -- / \ A - B ------ E' - F' \ / D' This is not really preserving the branch topology from before! The reason is that the commit `D` does not have `B` as ancestor, and therefore it gets rebased onto `B`. This is unintuitive behavior. Even worse, when recreating branch structure, most use cases would appear to want cousins *not* to be rebased onto the new base commit. For example, Git for Windows (the heaviest user of the Git garden shears, which served as the blueprint for --rebase-merges) frequently merges branches from `next` early, and these branches certainly do *not* want to be rebased. In the example above, the desired outcome would look like this: --- C' -- / \ A - B ------ E' - F' \ / -- D' -- Let's introduce the term "cousins" for such commits ("D" in the example), and let's not rebase them by default. For hypothetical use cases where cousins *do* need to be rebased, `git rebase --rebase=merges=rebase-cousins` needs to be used. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-25 14:29:40 +02:00
flags |= rebase_cousins > 0 ? TODO_LIST_REBASE_COUSINS : 0;
flags |= command == SHORTEN_OIDS ? TODO_LIST_SHORTEN_IDS : 0;
rebase -i: introduce --rebase-merges=[no-]rebase-cousins When running `git rebase --rebase-merges` non-interactively with an ancestor of HEAD as <upstream> (or leaving the todo list unmodified), we would ideally recreate the exact same commits as before the rebase. However, if there are commits in the commit range <upstream>.. that do not have <upstream> as direct ancestor (i.e. if `git log <upstream>..` would show commits that are omitted by `git log --ancestry-path <upstream>..`), this is currently not the case: we would turn them into commits that have <upstream> as direct ancestor. Let's illustrate that with a diagram: C / \ A - B - E - F \ / D Currently, after running `git rebase -i --rebase-merges B`, the new branch structure would be (pay particular attention to the commit `D`): --- C' -- / \ A - B ------ E' - F' \ / D' This is not really preserving the branch topology from before! The reason is that the commit `D` does not have `B` as ancestor, and therefore it gets rebased onto `B`. This is unintuitive behavior. Even worse, when recreating branch structure, most use cases would appear to want cousins *not* to be rebased onto the new base commit. For example, Git for Windows (the heaviest user of the Git garden shears, which served as the blueprint for --rebase-merges) frequently merges branches from `next` early, and these branches certainly do *not* want to be rebased. In the example above, the desired outcome would look like this: --- C' -- / \ A - B ------ E' - F' \ / -- D' -- Let's introduce the term "cousins" for such commits ("D" in the example), and let's not rebase them by default. For hypothetical use cases where cousins *do* need to be rebased, `git rebase --rebase=merges=rebase-cousins` needs to be used. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-25 14:29:40 +02:00
if (rebase_cousins >= 0 && !rebase_merges)
warning(_("--[no-]rebase-cousins has no effect without "
"--rebase-merges"));
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
if (command == CONTINUE && argc == 1)
return !!sequencer_continue(&opts);
if (command == ABORT && argc == 1)
return !!sequencer_remove_state(&opts);
if (command == MAKE_SCRIPT && argc > 1)
return !!sequencer_make_script(stdout, argc, argv, flags);
if ((command == SHORTEN_OIDS || command == EXPAND_OIDS) && argc == 1)
return !!transform_todos(flags);
if (command == CHECK_TODO_LIST && argc == 1)
return !!check_todo_list();
if (command == SKIP_UNNECESSARY_PICKS && argc == 1)
return !!skip_unnecessary_picks();
if (command == REARRANGE_SQUASH && argc == 1)
return !!rearrange_squash();
if (command == ADD_EXEC && argc == 2)
return !!sequencer_add_exec_commands(argv[1]);
rebase--helper: add a builtin helper for interactive rebases Git's interactive rebase is still implemented as a shell script, despite its complexity. This implies that it suffers from the portability point of view, from lack of expressibility, and of course also from performance. The latter issue is particularly serious on Windows, where we pay a hefty price for relying so much on POSIX. Unfortunately, being such a huge shell script also means that we missed the train when it would have been relatively easy to port it to C, and instead piled feature upon feature onto that poor script that originally never intended to be more than a slightly pimped cherry-pick in a loop. To open the road toward better performance (in addition to all the other benefits of C over shell scripts), let's just start *somewhere*. The approach taken here is to add a builtin helper that at first intends to take care of the parts of the interactive rebase that are most affected by the performance penalties mentioned above. In particular, after we spent all those efforts on preparing the sequencer to process rebase -i's git-rebase-todo scripts, we implement the `git rebase -i --continue` functionality as a new builtin, git-rebase--helper. Once that is in place, we can work gradually on tackling the rest of the technical debt. Note that the rebase--helper needs to learn about the transient --ff/--no-ff options of git-rebase, as the corresponding flag is not persisted to, and re-read from, the state directory. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-02-09 23:23:06 +01:00
usage_with_options(builtin_rebase_helper_usage, options);
}