git-commit-vandalism/git-rebase--interactive.sh

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remove #!interpreter line from shell libraries In a shell snippet meant to be sourced by other shell scripts, an opening #! line does more harm than good. The harm: - When the shell library is sourced, the interpreter and options from the #! line are not used. Specifying a particular shell can confuse the reader into thinking it is safe for the shell library to rely on idiosyncrasies of that shell. - Using #! instead of a plain comment drops a helpful visual clue that this is a shell library and not a self-contained script. - Tools such as lintian can use a #! line to tell when an installation script has failed by forgetting to set a script executable. This check does not work if shell libraries also start with a #! line. The good: - Text editors notice the #! line and use it for syntax highlighting if you try to edit the installed scripts (without ".sh" suffix) in place. The use of the #! for file type detection is not needed because Git's shell libraries are meant to be edited in source form (with ".sh" suffix). Replace the opening #! lines with comments. This involves tweaking the test harness's valgrind support to find shell libraries by looking for "# " in the first line instead of "#!" (see v1.7.6-rc3~7, 2011-06-17). Suggested by Russ Allbery through lintian. Thanks to Jeff King and Clemens Buchacher for further analysis. Tested by searching for non-executable scripts with #! line: find . -name .git -prune -o -type f -not -executable | while read file do read line <"$file" case $line in '#!'*) echo "$file" ;; esac done The only remaining scripts found are templates for shell scripts (unimplemented.sh, wrap-for-bin.sh) and sample input used in tests (t/t4034/perl/{pre,post}). Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-11-25 22:03:52 +01:00
# This shell script fragment is sourced by git-rebase to implement
# its interactive mode. "git rebase --interactive" makes it easy
# to fix up commits in the middle of a series and rearrange commits.
#
# Copyright (c) 2006 Johannes E. Schindelin
#
# The original idea comes from Eric W. Biederman, in
# https://public-inbox.org/git/m1odwkyuf5.fsf_-_@ebiederm.dsl.xmission.com/
#
# The file containing rebase commands, comments, and empty lines.
# This file is created by "git rebase -i" then edited by the user. As
# the lines are processed, they are removed from the front of this
# file and written to the tail of $done.
todo="$state_dir"/git-rebase-todo
GIT_CHERRY_PICK_HELP="$resolvemsg"
export GIT_CHERRY_PICK_HELP
comment_char=$(git config --get core.commentchar 2>/dev/null)
case "$comment_char" in
'' | auto)
comment_char="#"
;;
?)
;;
*)
comment_char=$(echo "$comment_char" | cut -c1)
;;
esac
orig_reflog_action="$GIT_REFLOG_ACTION"
comment_for_reflog () {
case "$orig_reflog_action" in
''|rebase*)
GIT_REFLOG_ACTION="rebase -i ($1)"
export GIT_REFLOG_ACTION
;;
esac
}
die_abort () {
apply_autostash
rm -rf "$state_dir"
die "$1"
}
has_action () {
test -n "$(git stripspace --strip-comments <"$1")"
}
git_sequence_editor () {
if test -z "$GIT_SEQUENCE_EDITOR"
then
GIT_SEQUENCE_EDITOR="$(git config sequence.editor)"
if [ -z "$GIT_SEQUENCE_EDITOR" ]
then
GIT_SEQUENCE_EDITOR="$(git var GIT_EDITOR)" || return $?
fi
fi
eval "$GIT_SEQUENCE_EDITOR" '"$@"'
}
expand_todo_ids() {
git rebase--helper --expand-ids
}
collapse_todo_ids() {
git rebase--helper --shorten-ids
}
# Switch to the branch in $into and notify it in the reflog
checkout_onto () {
comment_for_reflog start
GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name"
output git checkout $onto || die_abort "$(gettext "could not detach HEAD")"
git update-ref ORIG_HEAD $orig_head
}
get_missing_commit_check_level () {
check_level=$(git config --get rebase.missingCommitsCheck)
check_level=${check_level:-ignore}
# Don't be case sensitive
printf '%s' "$check_level" | tr 'A-Z' 'a-z'
}
# Initiate an action. If the cannot be any
# further action it may exec a command
# or exit and not return.
#
# TODO: Consider a cleaner return model so it
# never exits and always return 0 if process
# is complete.
#
# Parameter 1 is the action to initiate.
#
# Returns 0 if the action was able to complete
# and if 1 if further processing is required.
initiate_action () {
case "$1" in
continue)
exec git rebase--helper ${force_rebase:+--no-ff} $allow_empty_message \
--continue
;;
skip)
git rerere clear
exec git rebase--helper ${force_rebase:+--no-ff} $allow_empty_message \
--continue
;;
edit-todo)
exec git rebase--helper --edit-todo
;;
show-current-patch)
exec git show REBASE_HEAD --
;;
*)
return 1 # continue
;;
esac
}
init_basic_state () {
orig_head=$(git rev-parse --verify HEAD) || die "$(gettext "No HEAD?")"
mkdir -p "$state_dir" || die "$(eval_gettext "Could not create temporary \$state_dir")"
rm -f "$(git rev-parse --git-path REBASE_HEAD)"
: > "$state_dir"/interactive || die "$(gettext "Could not mark as interactive")"
write_basic_state
}
init_revisions_and_shortrevisions () {
shorthead=$(git rev-parse --short $orig_head)
shortonto=$(git rev-parse --short $onto)
if test -z "$rebase_root"
# this is now equivalent to ! -z "$upstream"
then
shortupstream=$(git rev-parse --short $upstream)
revisions=$upstream...$orig_head
shortrevisions=$shortupstream..$shorthead
else
revisions=$onto...$orig_head
shortrevisions=$shorthead
test -z "$squash_onto" ||
echo "$squash_onto" >"$state_dir"/squash-onto
fi
}
complete_action() {
test -s "$todo" || echo noop >> "$todo"
test -z "$autosquash" || git rebase--helper --rearrange-squash || exit
test -n "$cmd" && git rebase--helper --add-exec-commands "$cmd"
todocount=$(git stripspace --strip-comments <"$todo" | wc -l)
todocount=${todocount##* }
cat >>"$todo" <<EOF
$comment_char $(eval_ngettext \
"Rebase \$shortrevisions onto \$shortonto (\$todocount command)" \
"Rebase \$shortrevisions onto \$shortonto (\$todocount commands)" \
"$todocount")
EOF
git rebase--helper --append-todo-help ${keep_empty:+--keep-empty}
has_action "$todo" ||
return 2
cp "$todo" "$todo".backup
collapse_todo_ids
git_sequence_editor "$todo" ||
die_abort "$(gettext "Could not execute editor")"
has_action "$todo" ||
return 2
git rebase--helper --check-todo-list || {
ret=$?
checkout_onto
exit $ret
}
expand_todo_ids
test -n "$force_rebase" ||
onto="$(git rebase--helper --skip-unnecessary-picks)" ||
die "Could not skip unnecessary pick commands"
checkout_onto
require_clean_work_tree "rebase"
exec git rebase--helper ${force_rebase:+--no-ff} $allow_empty_message \
--continue
}
git_rebase__interactive () {
initiate_action "$action"
ret=$?
if test $ret = 0; then
return 0
fi
git rebase--helper --prepare-branch "$switch_to" ${verbose:+--verbose}
init_basic_state
init_revisions_and_shortrevisions
git rebase--helper --make-script ${keep_empty:+--keep-empty} \
rebase: introduce the --rebase-merges option Once upon a time, this here developer thought: wouldn't it be nice if, say, Git for Windows' patches on top of core Git could be represented as a thicket of branches, and be rebased on top of core Git in order to maintain a cherry-pick'able set of patch series? The original attempt to answer this was: git rebase --preserve-merges. However, that experiment was never intended as an interactive option, and it only piggy-backed on git rebase --interactive because that command's implementation looked already very, very familiar: it was designed by the same person who designed --preserve-merges: yours truly. Some time later, some other developer (I am looking at you, Andreas! ;-)) decided that it would be a good idea to allow --preserve-merges to be combined with --interactive (with caveats!) and the Git maintainer (well, the interim Git maintainer during Junio's absence, that is) agreed, and that is when the glamor of the --preserve-merges design started to fall apart rather quickly and unglamorously. The reason? In --preserve-merges mode, the parents of a merge commit (or for that matter, of *any* commit) were not stated explicitly, but were *implied* by the commit name passed to the `pick` command. This made it impossible, for example, to reorder commits. Not to mention to move commits between branches or, deity forbid, to split topic branches into two. Alas, these shortcomings also prevented that mode (whose original purpose was to serve Git for Windows' needs, with the additional hope that it may be useful to others, too) from serving Git for Windows' needs. Five years later, when it became really untenable to have one unwieldy, big hodge-podge patch series of partly related, partly unrelated patches in Git for Windows that was rebased onto core Git's tags from time to time (earning the undeserved wrath of the developer of the ill-fated git-remote-hg series that first obsoleted Git for Windows' competing approach, only to be abandoned without maintainer later) was really untenable, the "Git garden shears" were born [*1*/*2*]: a script, piggy-backing on top of the interactive rebase, that would first determine the branch topology of the patches to be rebased, create a pseudo todo list for further editing, transform the result into a real todo list (making heavy use of the `exec` command to "implement" the missing todo list commands) and finally recreate the patch series on top of the new base commit. That was in 2013. And it took about three weeks to come up with the design and implement it as an out-of-tree script. Needless to say, the implementation needed quite a few years to stabilize, all the while the design itself proved itself sound. With this patch, the goodness of the Git garden shears comes to `git rebase -i` itself. Passing the `--rebase-merges` option will generate a todo list that can be understood readily, and where it is obvious how to reorder commits. New branches can be introduced by inserting `label` commands and calling `merge <label>`. And once this mode will have become stable and universally accepted, we can deprecate the design mistake that was `--preserve-merges`. Link *1*: https://github.com/msysgit/msysgit/blob/master/share/msysGit/shears.sh Link *2*: https://github.com/git-for-windows/build-extra/blob/master/shears.sh Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-25 14:29:04 +02:00
${rebase_merges:+--rebase-merges} \
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
${rebase_cousins:+--rebase-cousins} \
$revisions ${restrict_revision+^$restrict_revision} >"$todo" ||
die "$(gettext "Could not generate todo list")"
complete_action
}