Re: [PATCH 3/6] rebase -i --root: let the sequencer handle even the initial part

[Johannes Schindelin]

Hi Stefan,

On Sat, 28 Apr 2018, Stefan Beller wrote:

> On Fri, Apr 27, 2018 at 3:31 PM, Johannes Schindelin
>  wrote:
> > In this developer's earlier attempt to accelerate interactive rebases by
> > converting large parts from Unix shell script into portable, performant
> > C, the --root handling was specifically excluded (to simplify the task a
> > little bit; it still took over a year to get that reduced set of patches
> > into Git proper).
> >
> > This patch ties up that loose end: now only --preserve-merges uses the
> > slow Unix shell script implementation to perform the interactive rebase.
> >
> > As the rebase--helper reports progress to stderr (unlike the scripted
> > interactive rebase, which reports it to stdout, of all places), we have
> > to adjust a couple of tests that did not expect that for `git rebase -i
> > --root`.
> >
> > This patch fixes -- at long last! -- the really old bug reported in
> > 6a6bc5bdc4d (add tests for rebasing root, 2013-06-06) that rebasing with
> > --root *always* rewrote the root commit, even if there were no changes.
> >
> > The bug still persists in --preserve-merges mode, of course, but that
> > mode will be deprecated as soon as the new --rebase-merges mode
> > stabilizes, anyway.
> >
> > Signed-off-by: Johannes Schindelin 
> > ---
> >  git-rebase--interactive.sh|  4 +++-
> >  t/t3404-rebase-interactive.sh | 19 +--
> >  t/t3421-rebase-topology-linear.sh |  6 +++---
> >  3 files changed, 19 insertions(+), 10 deletions(-)
> >
> > diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
> > index cbf44f86482..2f4941d0fc9 100644
> > --- a/git-rebase--interactive.sh
> > +++ b/git-rebase--interactive.sh
> > @@ -894,6 +894,8 @@ init_revisions_and_shortrevisions () {
> > else
> > revisions=$onto...$orig_head
> > shortrevisions=$shorthead
> > +   test -z "$squash_onto" ||
> > +   echo "$squash_onto" >"$state_dir"/squash-onto
> > fi
> >  }
> >
> > @@ -948,7 +950,7 @@ EOF
> > die "Could not skip unnecessary pick commands"
> >
> > checkout_onto
> > -   if test -z "$rebase_root" && test ! -d "$rewritten"
> > +   if test ! -d "$rewritten"
> 
> I have the impression this is the line that is really well
> explained in the commit message ("migrate to rebase
> helper even when there is $rebase_root set")
> 
> The rest of the patch is covered as "a couple of places
> where we adjust stdout to stderr"?

Correct.

Thanks for reviewing!
Dscho

Re: [PATCH 3/6] rebase -i --root: let the sequencer handle even the initial part

[Stefan Beller]

On Fri, Apr 27, 2018 at 3:31 PM, Johannes Schindelin
 wrote:
> In this developer's earlier attempt to accelerate interactive rebases by
> converting large parts from Unix shell script into portable, performant
> C, the --root handling was specifically excluded (to simplify the task a
> little bit; it still took over a year to get that reduced set of patches
> into Git proper).
>
> This patch ties up that loose end: now only --preserve-merges uses the
> slow Unix shell script implementation to perform the interactive rebase.
>
> As the rebase--helper reports progress to stderr (unlike the scripted
> interactive rebase, which reports it to stdout, of all places), we have
> to adjust a couple of tests that did not expect that for `git rebase -i
> --root`.
>
> This patch fixes -- at long last! -- the really old bug reported in
> 6a6bc5bdc4d (add tests for rebasing root, 2013-06-06) that rebasing with
> --root *always* rewrote the root commit, even if there were no changes.
>
> The bug still persists in --preserve-merges mode, of course, but that
> mode will be deprecated as soon as the new --rebase-merges mode
> stabilizes, anyway.
>
> Signed-off-by: Johannes Schindelin 
> ---
>  git-rebase--interactive.sh|  4 +++-
>  t/t3404-rebase-interactive.sh | 19 +--
>  t/t3421-rebase-topology-linear.sh |  6 +++---
>  3 files changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
> index cbf44f86482..2f4941d0fc9 100644
> --- a/git-rebase--interactive.sh
> +++ b/git-rebase--interactive.sh
> @@ -894,6 +894,8 @@ init_revisions_and_shortrevisions () {
> else
> revisions=$onto...$orig_head
> shortrevisions=$shorthead
> +   test -z "$squash_onto" ||
> +   echo "$squash_onto" >"$state_dir"/squash-onto
> fi
>  }
>
> @@ -948,7 +950,7 @@ EOF
> die "Could not skip unnecessary pick commands"
>
> checkout_onto
> -   if test -z "$rebase_root" && test ! -d "$rewritten"
> +   if test ! -d "$rewritten"

I have the impression this is the line that is really well
explained in the commit message ("migrate to rebase
helper even when there is $rebase_root set")

The rest of the patch is covered as "a couple of places
where we adjust stdout to stderr"?

Makes sense,
Stefan

[PATCH 3/6] rebase -i --root: let the sequencer handle even the initial part

[Johannes Schindelin]

In this developer's earlier attempt to accelerate interactive rebases by
converting large parts from Unix shell script into portable, performant
C, the --root handling was specifically excluded (to simplify the task a
little bit; it still took over a year to get that reduced set of patches
into Git proper).

This patch ties up that loose end: now only --preserve-merges uses the
slow Unix shell script implementation to perform the interactive rebase.

As the rebase--helper reports progress to stderr (unlike the scripted
interactive rebase, which reports it to stdout, of all places), we have
to adjust a couple of tests that did not expect that for `git rebase -i
--root`.

This patch fixes -- at long last! -- the really old bug reported in
6a6bc5bdc4d (add tests for rebasing root, 2013-06-06) that rebasing with
--root *always* rewrote the root commit, even if there were no changes.

The bug still persists in --preserve-merges mode, of course, but that
mode will be deprecated as soon as the new --rebase-merges mode
stabilizes, anyway.

Signed-off-by: Johannes Schindelin 
---
 git-rebase--interactive.sh|  4 +++-
 t/t3404-rebase-interactive.sh | 19 +--
 t/t3421-rebase-topology-linear.sh |  6 +++---
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index cbf44f86482..2f4941d0fc9 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -894,6 +894,8 @@ init_revisions_and_shortrevisions () {
else
revisions=$onto...$orig_head
shortrevisions=$shorthead
+   test -z "$squash_onto" ||
+   echo "$squash_onto" >"$state_dir"/squash-onto
fi
 }
 
@@ -948,7 +950,7 @@ EOF
die "Could not skip unnecessary pick commands"
 
checkout_onto
-   if test -z "$rebase_root" && test ! -d "$rewritten"
+   if test ! -d "$rewritten"
then
require_clean_work_tree "rebase"
exec git rebase--helper ${force_rebase:+--no-ff} 
$allow_empty_message \
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index 59c766540e5..c65826ddace 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1204,10 +1204,6 @@ test_expect_success 'drop' '
test A = $(git cat-file commit HEAD^^ | sed -ne \$p)
 '
 
-cat >expect expect actual.2 &&
+   cr_to_nl actual &&
test_i18ncmp expect actual &&
test D = $(git cat-file commit HEAD | sed -ne \$p)
 '
diff --git a/t/t3421-rebase-topology-linear.sh 
b/t/t3421-rebase-topology-linear.sh
index e7438ad06ac..99b2aac9219 100755
--- a/t/t3421-rebase-topology-linear.sh
+++ b/t/t3421-rebase-topology-linear.sh
@@ -328,9 +328,9 @@ test_run_rebase () {
test_cmp_rev c HEAD
"
 }
-test_run_rebase failure ''
-test_run_rebase failure -m
-test_run_rebase failure -i
+test_run_rebase success ''
+test_run_rebase success -m
+test_run_rebase success -i
 test_run_rebase failure -p
 
 test_run_rebase () {
-- 
2.17.0.windows.1.33.gfcbb1fa0445