[PATCH/RFCv2 1/2] git-rebase -i: add command "drop" to remove a commit

[PATCH/RFCv2 1/2] git-rebase -i: add command "drop" to remove a commit

[Galan Rémi]

Instead of removing a line to remove the commit, you can use the
command "drop" (just like "pick" or "edit"). It has the same effect as
deleting the line (removing the commit) except that you keep a visual
trace of your actions, allowing a better control and reducing the
possibility of removing a commit by mistake.

Signed-off-by: Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr>
---
 Documentation/git-rebase.txt  |  3 +++
 git-rebase--interactive.sh    |  3 ++-
 t/lib-rebase.sh               |  4 ++--
 t/t3404-rebase-interactive.sh | 11 +++++++++++
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 1d01baa..9cf3760 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -514,6 +514,9 @@ rebasing.
 If you just want to edit the commit message for a commit, replace the
 command "pick" with the command "reword".
 
+To drop a commit, replace the command "pick" with "drop", or just
+delete its line.
+
 If you want to fold two or more commits into one, replace the command
 "pick" for the second and subsequent commits with "squash" or "fixup".
 If the commits had different authors, the folded commit will be
diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index bab0dcc..2882276 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -152,6 +152,7 @@ Commands:
  s, squash = use commit, but meld into previous commit
  f, fixup = like "squash", but discard this commit's log message
  x, exec = run command (the rest of the line) using shell
+ d, drop = remove commit
 
 These lines can be re-ordered; they are executed from top to bottom.
 
@@ -505,7 +506,7 @@ do_next () {
 	rm -f "$msg" "$author_script" "$amend" || exit
 	read -r command sha1 rest < "$todo"
 	case "$command" in
-	"$comment_char"*|''|noop)
+	"$comment_char"*|''|noop|drop|d)
 		mark_action_done
 		;;
 	pick|p)
diff --git a/t/lib-rebase.sh b/t/lib-rebase.sh
index 6bd2522..fdbc900 100644
--- a/t/lib-rebase.sh
+++ b/t/lib-rebase.sh
@@ -14,7 +14,7 @@
 #       specified line.
 #
 #   "<cmd> <lineno>" -- add a line with the specified command
-#       ("squash", "fixup", "edit", or "reword") and the SHA1 taken
+#       ("squash", "fixup", "edit", "reword" or "drop") and the SHA1 taken
 #       from the specified line.
 #
 #   "exec_cmd_with_args" -- add an "exec cmd with args" line.
@@ -46,7 +46,7 @@ set_fake_editor () {
 	action=pick
 	for line in $FAKE_LINES; do
 		case $line in
-		squash|fixup|edit|reword)
+		squash|fixup|edit|reword|drop)
 			action="$line";;
 		exec*)
 			echo "$line" | sed 's/_/ /g' >> "$1";;
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index ac429a0..1bad068 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1102,4 +1102,15 @@ test_expect_success 'rebase -i commits that overwrite untracked files (no ff)' '
 	test $(git cat-file commit HEAD | sed -ne \$p) = I
 '
 
+test_expect_success 'drop' '
+	git checkout master &&
+	test_when_finished "git checkout master" &&
+	git checkout -b dropBranchTest master &&
+	set_fake_editor &&
+	FAKE_LINES="1 drop 2 3 drop 4 5" git rebase -i --root &&
+	test E = $(git cat-file commit HEAD | sed -ne \$p) &&
+	test C = $(git cat-file commit HEAD^ | sed -ne \$p) &&
+	test A = $(git cat-file commit HEAD^^ | sed -ne \$p)
+'
+
 test_done
-- 
2.4.1.363.g9535a9c

[PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Galan Rémi]

Check if commits were removed (i.e. a line was deleted) and print
warnings or abort git rebase according to the value of the
configuration variable rebase.checkLevel.

Add the configuration variable rebase.checkLevel.
    - When unset or set to "ignore", no checking is done.
    - When set to "warn", the commits are checked, warnings are
      displayed but git rebase still proceeds.
    - When set to "error", the commits are checked, warnings are
      displayed and the rebase is aborted.

rebase.checkLevel defaults to "ignore".

Signed-off-by: Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr>
---
 Documentation/config.txt      |   9 ++++
 Documentation/git-rebase.txt  |   6 +++
 git-rebase--interactive.sh    | 105 ++++++++++++++++++++++++++++++++++++++++++
 t/t3404-rebase-interactive.sh |  10 +++-
 4 files changed, 129 insertions(+), 1 deletion(-)

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 5f76e8c..e2e5554 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -2160,6 +2160,15 @@ rebase.autoStash::
 	successful rebase might result in non-trivial conflicts.
 	Defaults to false.
 
+rebase.checkLevel::
+	If set to "warn", git rebase -i will print a warning if some
+	commits are removed (i.e. a line was deleted) or if some
+	commits appear more than one time (e.g. the same commit is
+	picked twice), however the rebase will still proceed. If set
+	to "error", it will print the previous warnings and abort the
+	rebase. If set to "ignore", no checking is done.  Defaults to
+	"ignore".
+
 receive.advertiseAtomic::
 	By default, git-receive-pack will advertise the atomic push
 	capability to its clients. If you don't want to this capability
diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 9cf3760..d348ca2 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -213,6 +213,12 @@ rebase.autoSquash::
 rebase.autoStash::
 	If set to true enable '--autostash' option by default.
 
+rebase.checkLevel::
+	If set to "warn" print warnings about removed commits and
+	duplicated commits in interactive mode. If set to "error"
+	print the warnings and abort the rebase. If set to "ignore" no
+	checking is done. "ignore" by default.
+
 OPTIONS
 -------
 --onto <newbase>::
diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 2882276..58da6ee 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -837,6 +837,109 @@ add_exec_commands () {
 	mv "$1.new" "$1"
 }
 
+# Print the list of the SHA-1 of the commits
+# from a todo list in a file.
+# $1: todo-file, $2: outfile
+todo_list_to_sha_list () {
+	todo_list=$(git stripspace --strip-comments <"$1")
+	temp_file=$(mktemp)
+	echo "$todo_list" >$temp_file
+	while read -r command sha1 rest
+	do
+		case $command in
+		x|"exec")
+			;;
+		*)
+			printf "%s\n" "$sha1"
+			;;
+		esac
+	done <$temp_file >"$2"
+	rm $temp_file
+}
+
+# Transforms SHA-1 list in argument
+# to a list of commits (in place)
+# Doesn't check if the SHA-1 are commits.
+# $1: file with long SHA-1 list
+long_sha_to_commit_list () {
+	short_missing=""
+	git_command="git show --oneline"
+	get_line_command="head -n 1"
+	temp_file=$(mktemp)
+	while read -r sha
+	do
+		if test -n "$sha"
+		then
+			commit=$($git_command $sha | $get_line_command)
+			if test -n "$commit"
+			then
+				printf "%s\n" "$commit"
+			fi
+		fi
+	done <"$1" >$temp_file
+	mv $temp_file "$1"
+}
+
+# Use warn for each line of a file
+# $1: file to warn
+warn_file () {
+	while read -r line
+	do
+		warn " - $line"
+	done <"$1"
+}
+
+# Check if the user dropped some commits by mistake
+# Behaviour determined by .gitconfig.
+check_commits () {
+	checkLevel=$(git config --get rebase.checkLevel)
+	checkLevel=${checkLevel:-ignore}
+	# To lowercase
+	checkLevel=$(echo "$checkLevel" | tr 'A-Z' 'a-z')
+
+	case "$checkLevel" in
+	warn|error)
+		# Get the SHA-1 of the commits
+		todo_list_to_sha_list "$todo".backup "$todo".oldsha1
+		todo_list_to_sha_list "$todo" "$todo".newsha1
+
+		# Sort the SHA-1 and compare them
+		echo "$(sort -u "$todo".oldsha1)" >"$todo".oldsha1
+		echo "$(sort -u "$todo".newsha1)" >"$todo".newsha1
+		echo "$(comm -2 -3 "$todo".oldsha1 "$todo".newsha1)" >"$todo".miss
+
+		# Make the list user-friendly
+		long_sha_to_commit_list "$todo".miss
+
+		# Check missing commits
+		if test -s "$todo".miss
+		then
+			warn "Warning : some commits may have been dropped" \
+				"accidentally."
+			warn "Dropped commits (in no relevent order):"
+			warn_file "$todo".miss
+			warn ""
+			warn "To avoid this message, use \"drop\" to" \
+				"explicitly remove a commit."
+			warn "Use git --config rebase.checkLevel to change" \
+				"the level of warnings (ignore,warn,error)."
+			warn ""
+
+			if test "$checkLevel" = error
+			then
+				die_abort "Rebase aborted due to dropped commits."
+			fi
+		fi
+		;;
+	ignore)
+		;;
+	*)
+		warn "Unrecognized setting $checkLevel for option" \
+			"rebase.checkLevel in git rebase -i."
+		;;
+	esac
+}
+
 # The whole contents of this file is run by dot-sourcing it from
 # inside a shell function.  It used to be that "return"s we see
 # below were not inside any function, and expected to return
@@ -1079,6 +1182,8 @@ has_action "$todo" ||
 
 expand_todo_ids
 
+check_commits
+
 test -d "$rewritten" || test -n "$force_rebase" || skip_unnecessary_picks
 
 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name"
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 1bad068..d3a9ed5 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1103,7 +1103,6 @@ test_expect_success 'rebase -i commits that overwrite untracked files (no ff)' '
 '
 
 test_expect_success 'drop' '
-	git checkout master &&
 	test_when_finished "git checkout master" &&
 	git checkout -b dropBranchTest master &&
 	set_fake_editor &&
@@ -1113,4 +1112,13 @@ test_expect_success 'drop' '
 	test A = $(git cat-file commit HEAD^^ | sed -ne \$p)
 '
 
+test_expect_success 'rebase -i respects rebase.checkLevel' '
+	test_config rebase.checkLevel error &&
+	test_when_finished "git checkout master" &&
+	git checkout -b tmp2 master &&
+	set_fake_editor &&
+	test_must_fail env FAKE_LINES="1 2 3 4" git rebase -i --root &&
+	test E = $(git cat-file commit HEAD | sed -ne \$p)
+'
+
 test_done
-- 
2.4.1.363.g9535a9c

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Eric Sunshine]

On Mon, Jun 1, 2015 at 7:52 AM, Galan Rémi
<remi.galan-alfonso@ensimag.grenoble-inp.fr> wrote:
> Check if commits were removed (i.e. a line was deleted) and print
> warnings or abort git rebase according to the value of the
> configuration variable rebase.checkLevel.
>
> Add the configuration variable rebase.checkLevel.
>     - When unset or set to "ignore", no checking is done.
>     - When set to "warn", the commits are checked, warnings are
>       displayed but git rebase still proceeds.
>     - When set to "error", the commits are checked, warnings are
>       displayed and the rebase is aborted.
>
> rebase.checkLevel defaults to "ignore".
>
> Signed-off-by: Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr>
> ---
> diff --git a/Documentation/config.txt b/Documentation/config.txt
> index 5f76e8c..e2e5554 100644
> --- a/Documentation/config.txt
> +++ b/Documentation/config.txt
> @@ -2160,6 +2160,15 @@ rebase.autoStash::
>         successful rebase might result in non-trivial conflicts.
>         Defaults to false.
>
> +rebase.checkLevel::
> +       If set to "warn", git rebase -i will print a warning if some
> +       commits are removed (i.e. a line was deleted) or if some
> +       commits appear more than one time (e.g. the same commit is
> +       picked twice), however the rebase will still proceed. If set

The cover letter says that v2 no longer checks for a duplicate,
however, this documentation still mentions it.

> +       to "error", it will print the previous warnings and abort the
> +       rebase. If set to "ignore", no checking is done.  Defaults to
> +       "ignore".
> +
>  receive.advertiseAtomic::
>         By default, git-receive-pack will advertise the atomic push
>         capability to its clients. If you don't want to this capability
> diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
> index 9cf3760..d348ca2 100644
> --- a/Documentation/git-rebase.txt
> +++ b/Documentation/git-rebase.txt
> @@ -213,6 +213,12 @@ rebase.autoSquash::
>  rebase.autoStash::
>         If set to true enable '--autostash' option by default.
>
> +rebase.checkLevel::
> +       If set to "warn" print warnings about removed commits and
> +       duplicated commits in interactive mode. If set to "error"

Same here.

> +       print the warnings and abort the rebase. If set to "ignore" no
> +       checking is done. "ignore" by default.
> +
> diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
> index 1bad068..d3a9ed5 100755
> --- a/t/t3404-rebase-interactive.sh
> +++ b/t/t3404-rebase-interactive.sh
> @@ -1103,7 +1103,6 @@ test_expect_success 'rebase -i commits that overwrite untracked files (no ff)' '
>  '
>
>  test_expect_success 'drop' '
> -       git checkout master &&
>         test_when_finished "git checkout master" &&
>         git checkout -b dropBranchTest master &&

This "cleanup" change might deserve its own test (or at least a
mention in the commit message).

>         set_fake_editor &&
> @@ -1113,4 +1112,13 @@ test_expect_success 'drop' '
>         test A = $(git cat-file commit HEAD^^ | sed -ne \$p)
>  '
>
> +test_expect_success 'rebase -i respects rebase.checkLevel' '
> +       test_config rebase.checkLevel error &&
> +       test_when_finished "git checkout master" &&
> +       git checkout -b tmp2 master &&
> +       set_fake_editor &&
> +       test_must_fail env FAKE_LINES="1 2 3 4" git rebase -i --root &&
> +       test E = $(git cat-file commit HEAD | sed -ne \$p)
> +'

Shouldn't you also explicitly test "warn" and "ignore" modes?

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Eric Sunshine]

On Mon, Jun 1, 2015 at 7:16 PM, Eric Sunshine <sunshine@sunshineco.com> wrote:
> On Mon, Jun 1, 2015 at 7:52 AM, Galan Rémi
> <remi.galan-alfonso@ensimag.grenoble-inp.fr> wrote:
>>  test_expect_success 'drop' '
>> -       git checkout master &&
>>         test_when_finished "git checkout master" &&
>>         git checkout -b dropBranchTest master &&
>
> This "cleanup" change might deserve its own test (or at least a
> mention in the commit message).

"...might deserve its own _patch_..."

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Matthieu Moy]

Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr> writes:

> Check if commits were removed (i.e. a line was deleted) and print
> warnings or abort git rebase according to the value of the
> configuration variable rebase.checkLevel.

checkLevel does not seem to be a good name, because it doesn't say
_what_ is checked. I don't have really good proposal in mind, but maybe

rebase.todoListCheckLevel
rebase.missinLinesCheckLevel

?

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Remi Galan Alfonso]

Eric Sunshine <sunshine@sunshineco.com> writes:
> > +rebase.checkLevel::
> > +       If set to "warn", git rebase -i will print a warning if some
> > +       commits are removed (i.e. a line was deleted) or if some
> > +       commits appear more than one time (e.g. the same commit is
> > +       picked twice), however the rebase will still proceed. If set
> 
> The cover letter says that v2 no longer checks for a duplicate,
> however, this documentation still mentions it.
> 
> > +rebase.checkLevel::
> > +       If set to "warn" print warnings about removed commits and
> > +       duplicated commits in interactive mode. If set to "error"
> 
> Same here.

I forgot to modify the documentation, really sorry about
that.
Corrected here.

Eric Sunshine <sunshine@sunshineco.com> writes:
> >  test_expect_success 'drop' '
> > -       git checkout master &&
> >         test_when_finished "git checkout master" &&
> >         git checkout -b dropBranchTest master &&
> 
> This "cleanup" change might deserve its own patch (or at least a
> mention in the commit message).

I will rather move the this cleanup to the first part of this patch,
where the test was added (it should cause no problem, since the patch
is still in discussion), it makes more sense. I actually thought that
was what I did but seems like I was wrong.

I forgot to double check my patch this time, and it is showing, my
bad.

Eric Sunshine <sunshine@sunshineco.com> writes:
> > +test_expect_success 'rebase -i respects rebase.checkLevel' '
> > +       test_config rebase.checkLevel error &&
> > +       test_when_finished "git checkout master" &&
> > +       git checkout -b tmp2 master &&
> > +       set_fake_editor &&
> > +       test_must_fail env FAKE_LINES="1 2 3 4" git rebase -i --root &&
> > +       test E = $(git cat-file commit HEAD | sed -ne \$p)
> > +'
> 
> Shouldn't you also explicitly test "warn" and "ignore" modes?

I don't think testing "ignore" is really necessary since it
corresponds to the default behaviour, it is thus silently tested by
the other tests.
Either way, I will add a test for "warn".

Rémi

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Remi Galan Alfonso]

Matthieu Moy <Matthieu.Moy@grenoble-inp.fr> writes:
> Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr> writes:
> 
> > Check if commits were removed (i.e. a line was deleted) and print
> > warnings or abort git rebase according to the value of the
> > configuration variable rebase.checkLevel.
> 
> checkLevel does not seem to be a good name, because it doesn't say
> _what_ is checked. I don't have really good proposal in mind, but maybe
> 
> rebase.todoListCheckLevel
> rebase.missinLinesCheckLevel
> 
> ?

I agree that we could use a better name.

I'm thinking about
   > rebase.missingLinesCheckLevel
   or
   rebase.missingCommitsCheckLevel
but I am worried that these names are too long.
Maybe
   rebase.dropCheckLevel

I don't really have better propositions right now.

Rémi

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Eric Sunshine]

On Tue, Jun 2, 2015 at 3:42 AM, Remi Galan Alfonso
<remi.galan-alfonso@ensimag.grenoble-inp.fr> wrote:
> Eric Sunshine <sunshine@sunshineco.com> writes:
>> > +test_expect_success 'rebase -i respects rebase.checkLevel' '
>> > +       test_config rebase.checkLevel error &&
>> > +       test_when_finished "git checkout master" &&
>> > +       git checkout -b tmp2 master &&
>> > +       set_fake_editor &&
>> > +       test_must_fail env FAKE_LINES="1 2 3 4" git rebase -i --root &&
>> > +       test E = $(git cat-file commit HEAD | sed -ne \$p)
>> > +'
>>
>> Shouldn't you also explicitly test "warn" and "ignore" modes?
>
> I don't think testing "ignore" is really necessary since it
> corresponds to the default behaviour, it is thus silently tested by
> the other tests.

Although the underlying behavior of "ignore" may be the same as the
default, you also want to check that higher-level machinery for
recognizing the "ignore" option is working correctly, which is why
checking "ignore" explicitly is a reasonable thing to do.

> Either way, I will add a test for "warn".

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Remi Galan Alfonso]

Eric Sunshine <sunshine@sunshineco.com> writes: 
> Although the underlying behavior of "ignore" may be the same as the 
> default, you also want to check that higher-level machinery for 
> recognizing the "ignore" option is working correctly, which is why 
> checking "ignore" explicitly is a reasonable thing to do. 

Noted, I'm adding a test for "ignore". 

Thank you, 

Rémi 

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Junio C Hamano]

Matthieu Moy <Matthieu.Moy@grenoble-inp.fr> writes:

> Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr> writes:
>
>> Check if commits were removed (i.e. a line was deleted) and print
>> warnings or abort git rebase according to the value of the
>> configuration variable rebase.checkLevel.
>
> checkLevel does not seem to be a good name, because it doesn't say
> _what_ is checked. I don't have really good proposal in mind, but maybe
>
> rebase.todoListCheckLevel
> rebase.missinLinesCheckLevel

Yeah, with s/sin/sing/, but the above makes more sense.  It may be
that we probably do not even need "Level" there in the name.

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Remi Galan Alfonso]

I'm going to try to change the die_abort in this patch by a die, so
that the user can use rebase --edit-todo afterward. This way, adding
the checking on the SHA-1 for the 'drop' command (discussed in 1/2)
(and also maybe the other commands requiring a correct SHA-1
corresponding to a commit) to the 2/2 part would make a bit more
sense. Though I still see some other issues with this, I agree that it
makes more sense in 2/2 rather than in 1/2 (some more checking in a
future patch would be a good idea).

(So far I've tried rather quickly, but it doesn't seem as easy as I
originally though, working on it though)

Rémi

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Remi Galan Alfonso]

Eric Sunshine <sunshine@sunshineco.com> writes:

> > +test_expect_success 'rebase -i respects rebase.missingCommitsCheck=ignore' '
> > +       test_config rebase.missingCommitsCheck ignore &&
> > +       test_when_finished "git checkout master &&
> > +               git branch -D tmp2" &&
> 
> Strange indentation.

Considering that 'git branch -D tmp2' is a part of test_when_finished,
I wasn't sure of how it was supposed to be indented, so I did it this
way to show that it was still within test_when_finished and not a
separate command.
> 	test_when_finished "git checkout master &&
> 	git branch -D tmp2" &&
Doesn't seem as clear, especially if you quickly read the lines.

For now, I have removed the tab.
Also the other points have been corrected.

Thank you,
Rémi

Re: [PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Eric Sunshine]

On Wednesday, June 3, 2015, Galan Rémi
<remi.galan-alfonso@ensimag.grenoble-inp.fr> wrote:
> Check if commits were removed (i.e. a line was deleted) and print
> warnings or abort git rebase depending on the value of the
> configuration variable rebase.missingCommits.

A few comments below in addition to those already made by Matthieu...

> diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
> index 8960083..f369d2c 100755
> --- a/t/t3404-rebase-interactive.sh
> +++ b/t/t3404-rebase-interactive.sh
> @@ -1112,4 +1112,67 @@ test_expect_success 'drop' '
>         test A = $(git cat-file commit HEAD^^ | sed -ne \$p)
>  '
>
> +cat >expect <<EOF
> +Successfully rebased and updated refs/heads/tmp2.
> +EOF
> +
> +test_expect_success 'rebase -i respects rebase.missingCommitsCheck=ignore' '
> +       test_config rebase.missingCommitsCheck ignore &&
> +       test_when_finished "git checkout master &&
> +               git branch -D tmp2" &&

Strange indentation.

> +       git checkout -b tmp2 master &&
> +       set_fake_editor &&
> +       FAKE_LINES="1 2 3 4" \
> +               git rebase -i --root 2>warning &&

The file containing the actual output is usually spelled "actual".

> +       test D = $(git cat-file commit HEAD | sed -ne \$p) &&
> +       test_cmp warning expect

The arguments to test_cmp are usually reversed so that 'expect' comes
before 'actual', which results in a more natural-feeling diff when
test_cmp detects that the files differ.

These comments apply to remaining new tests, as well.

> +'
> +
> +cat >expect <<EOF
> +Warning: some commits may have been dropped accidentally.
> +Dropped commits (newer to older):
> + - $(git rev-list --pretty=oneline --abbrev-commit -1 master)
> +
> +To avoid this message, use "drop" to explicitly remove a commit.
> +Use git --config rebase.missingCommitsCheck to change the level of warnings (ignore, warn, error).
> +
> +Successfully rebased and updated refs/heads/tmp2.
> +EOF
> +
> +test_expect_success 'rebase -i respects rebase.missingCommitsCheck=warn' '
> +       test_config rebase.missingCommitsCheck warn &&
> +       test_when_finished "git checkout master &&
> +               git branch -D tmp2" &&
> +       git checkout -b tmp2 master &&
> +       set_fake_editor &&
> +       FAKE_LINES="1 2 3 4" \
> +               git rebase -i --root 2>warning &&
> +       test D = $(git cat-file commit HEAD | sed -ne \$p) &&
> +       test_cmp warning expect
> +'
> +
> +cat >expect <<EOF
> +Warning: some commits may have been dropped accidentally.
> +Dropped commits (newer to older):
> + - $(git rev-list --pretty=oneline --abbrev-commit -1 master)
> + - $(git rev-list --pretty=oneline --abbrev-commit -1 master~2)
> +
> +To avoid this message, use "drop" to explicitly remove a commit.
> +Use git --config rebase.missingCommitsCheck to change the level of warnings (ignore, warn, error).
> +
> +Rebase aborted due to dropped commits.
> +EOF
> +
> +test_expect_success 'rebase -i respects rebase.missingCommitsCheck=error' '
> +       test_config rebase.missingCommitsCheck error &&
> +       test_when_finished "git checkout master &&
> +               git branch -D tmp2" &&
> +       git checkout -b tmp2 master &&
> +       set_fake_editor &&
> +       test_must_fail env FAKE_LINES="1 2 4" \
> +               git rebase -i --root 2>warning &&
> +       test E = $(git cat-file commit HEAD | sed -ne \$p) &&
> +       test_cmp warning expect
> +'
> +
>  test_done
> --
> 2.4.2.389.geaf7ccf

[PATCH/RFCv2 2/2] git rebase -i: warn about removed commits

[Galan Rémi]

Check if commits were removed (i.e. a line was deleted) and print
warnings or abort git rebase according to the value of the
configuration variable rebase.checkLevel.

Add the configuration variable rebase.checkLevel.
    - When unset or set to "ignore", no checking is done.
    - When set to "warn", the commits are checked, warnings are
      displayed but git rebase still proceeds.
    - When set to "error", the commits are checked, warnings are
      displayed and the rebase is aborted.

rebase.checkLevel defaults to "ignore".

Signed-off-by: Galan Rémi <remi.galan-alfonso@ensimag.grenoble-inp.fr>
---
 Documentation/config.txt      |   9 ++++
 Documentation/git-rebase.txt  |   6 +++
 git-rebase--interactive.sh    | 105 ++++++++++++++++++++++++++++++++++++++++++
 t/t3404-rebase-interactive.sh |  10 +++-
 4 files changed, 129 insertions(+), 1 deletion(-)

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 5f76e8c..e2e5554 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -2160,6 +2160,15 @@ rebase.autoStash::
 	successful rebase might result in non-trivial conflicts.
 	Defaults to false.
 
+rebase.checkLevel::
+	If set to "warn", git rebase -i will print a warning if some
+	commits are removed (i.e. a line was deleted) or if some
+	commits appear more than one time (e.g. the same commit is
+	picked twice), however the rebase will still proceed. If set
+	to "error", it will print the previous warnings and abort the
+	rebase. If set to "ignore", no checking is done.  Defaults to
+	"ignore".
+
 receive.advertiseAtomic::
 	By default, git-receive-pack will advertise the atomic push
 	capability to its clients. If you don't want to this capability
diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
index 9cf3760..d348ca2 100644
--- a/Documentation/git-rebase.txt
+++ b/Documentation/git-rebase.txt
@@ -213,6 +213,12 @@ rebase.autoSquash::
 rebase.autoStash::
 	If set to true enable '--autostash' option by default.
 
+rebase.checkLevel::
+	If set to "warn" print warnings about removed commits and
+	duplicated commits in interactive mode. If set to "error"
+	print the warnings and abort the rebase. If set to "ignore" no
+	checking is done. "ignore" by default.
+
 OPTIONS
 -------
 --onto <newbase>::
diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 2882276..58da6ee 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -837,6 +837,109 @@ add_exec_commands () {
 	mv "$1.new" "$1"
 }
 
+# Print the list of the SHA-1 of the commits
+# from a todo list in a file.
+# $1: todo-file, $2: outfile
+todo_list_to_sha_list () {
+	todo_list=$(git stripspace --strip-comments <"$1")
+	temp_file=$(mktemp)
+	echo "$todo_list" >$temp_file
+	while read -r command sha1 rest
+	do
+		case $command in
+		x|"exec")
+			;;
+		*)
+			printf "%s\n" "$sha1"
+			;;
+		esac
+	done <$temp_file >"$2"
+	rm $temp_file
+}
+
+# Transforms SHA-1 list in argument
+# to a list of commits (in place)
+# Doesn't check if the SHA-1 are commits.
+# $1: file with long SHA-1 list
+long_sha_to_commit_list () {
+	short_missing=""
+	git_command="git show --oneline"
+	get_line_command="head -n 1"
+	temp_file=$(mktemp)
+	while read -r sha
+	do
+		if test -n "$sha"
+		then
+			commit=$($git_command $sha | $get_line_command)
+			if test -n "$commit"
+			then
+				printf "%s\n" "$commit"
+			fi
+		fi
+	done <"$1" >$temp_file
+	mv $temp_file "$1"
+}
+
+# Use warn for each line of a file
+# $1: file to warn
+warn_file () {
+	while read -r line
+	do
+		warn " - $line"
+	done <"$1"
+}
+
+# Check if the user dropped some commits by mistake
+# Behaviour determined by .gitconfig.
+check_commits () {
+	checkLevel=$(git config --get rebase.checkLevel)
+	checkLevel=${checkLevel:-ignore}
+	# To lowercase
+	checkLevel=$(echo "$checkLevel" | tr 'A-Z' 'a-z')
+
+	case "$checkLevel" in
+	warn|error)
+		# Get the SHA-1 of the commits
+		todo_list_to_sha_list "$todo".backup "$todo".oldsha1
+		todo_list_to_sha_list "$todo" "$todo".newsha1
+
+		# Sort the SHA-1 and compare them
+		echo "$(sort -u "$todo".oldsha1)" >"$todo".oldsha1
+		echo "$(sort -u "$todo".newsha1)" >"$todo".newsha1
+		echo "$(comm -2 -3 "$todo".oldsha1 "$todo".newsha1)" >"$todo".miss
+
+		# Make the list user-friendly
+		long_sha_to_commit_list "$todo".miss
+
+		# Check missing commits
+		if test -s "$todo".miss
+		then
+			warn "Warning : some commits may have been dropped" \
+				"accidentally."
+			warn "Dropped commits (in no relevent order):"
+			warn_file "$todo".miss
+			warn ""
+			warn "To avoid this message, use \"drop\" to" \
+				"explicitly remove a commit."
+			warn "Use git --config rebase.checkLevel to change" \
+				"the level of warnings (ignore,warn,error)."
+			warn ""
+
+			if test "$checkLevel" = error
+			then
+				die_abort "Rebase aborted due to dropped commits."
+			fi
+		fi
+		;;
+	ignore)
+		;;
+	*)
+		warn "Unrecognized setting $checkLevel for option" \
+			"rebase.checkLevel in git rebase -i."
+		;;
+	esac
+}
+
 # The whole contents of this file is run by dot-sourcing it from
 # inside a shell function.  It used to be that "return"s we see
 # below were not inside any function, and expected to return
@@ -1079,6 +1182,8 @@ has_action "$todo" ||
 
 expand_todo_ids
 
+check_commits
+
 test -d "$rewritten" || test -n "$force_rebase" || skip_unnecessary_picks
 
 GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name"
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 1bad068..d3a9ed5 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1103,7 +1103,6 @@ test_expect_success 'rebase -i commits that overwrite untracked files (no ff)' '
 '
 
 test_expect_success 'drop' '
-	git checkout master &&
 	test_when_finished "git checkout master" &&
 	git checkout -b dropBranchTest master &&
 	set_fake_editor &&
@@ -1113,4 +1112,13 @@ test_expect_success 'drop' '
 	test A = $(git cat-file commit HEAD^^ | sed -ne \$p)
 '
 
+test_expect_success 'rebase -i respects rebase.checkLevel' '
+	test_config rebase.checkLevel error &&
+	test_when_finished "git checkout master" &&
+	git checkout -b tmp2 master &&
+	set_fake_editor &&
+	test_must_fail env FAKE_LINES="1 2 3 4" git rebase -i --root &&
+	test E = $(git cat-file commit HEAD | sed -ne \$p)
+'
+
 test_done
-- 
2.4.1.363.g9535a9c