Re: [PATCH 1/3] rebase: avoid non-function use of "return" on FreeBSD

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Apr 11, 2014, at 10:30, Matthieu Moy wrote:
"Kyle J. McKay" <mackyle@xxxxxxxxx> writes:

There are already nested functions with file inclusion between both
levels of nesting in git-rebase--interactive.sh and git-rebase--
merge.sh now, so it's not introducing anything new.

OK, so it's less serious than I thought. But still, we're introducing a function with 3 levels of nesting, split accross files, in an area where
we know that at least one shell is buggy ...

Currently in maint:

The current code in maint does this:

git-rebase.sh: top-level
  git-rebase.sh: run_specific_rebase()
    git-rebase.sh: run_specific_rebase_internal() -- contains "dot"
git-rebase--interactive.sh: top-level (using --continue or -- skip)
        git-rebase--interactive.sh: do_rest
          git-rebase--interactive.sh: do_next
            git-rebase--interactive.sh: record_in_rewritten
              git-rebase--interactive.sh: flush_rewritten_pending

So I really do not see the additional level of nesting as an issue since we've already got much more than 3 levels of nesting going on now. If nesting was going to be a problem, something would have broken already. In fact, since the follow on patch removes the run_specific_rebase_internal function what we would have after the originally proposed first two patches is:

git-rebase.sh: top-level
  git-rebase.sh: run_specific_rebase() -- contains "dot"
    git-rebase--interactive.sh: top-level (using --continue or --skip)
      git-rebase--interactive.sh: git_rebase__interactive
        git-rebase--interactive.sh: do_rest
          git-rebase--interactive.sh: do_next
            git-rebase--interactive.sh: record_in_rewritten
              git-rebase--interactive.sh: flush_rewritten_pending

Which has exactly the same nesting depth albeit the "dot" has moved up one level.

IOW, why not move the whole run_specific_rebase_internal function to
git-rebase--$type?

So what change are you proposing exactly?

Something along the lines of this:

diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index 6046778..5dfbf14 100644
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -820,6 +820,7 @@ add_exec_commands () {
	mv "$1.new" "$1"
}

+run_specific_rebase_infile() {
case "$action" in
continue)
	# do we have anything to commit?
@@ -1055,3 +1056,4 @@ GIT_REFLOG_ACTION="$GIT_REFLOG_ACTION: checkout $onto_name"
output git checkout $onto || die_abort "could not detach HEAD"
git update-ref ORIG_HEAD $orig_head
do_rest
+}
diff --git a/git-rebase--merge.sh b/git-rebase--merge.sh
index d84f412..907aa46 100644
--- a/git-rebase--merge.sh
+++ b/git-rebase--merge.sh
@@ -99,6 +99,7 @@ finish_rb_merge () {
	say All done.
}

+run_specific_rebase_infile () {
case "$action" in
continue)
	read_state
@@ -149,3 +150,4 @@ do
done

finish_rb_merge
+}


The problem with these changes, particularly the git-rebase-- interactive.sh one is that a bunch of code is still run when the file is "dot" included. With the changes to git-rebase.sh, that code will now run regardless of the action and it will run before it would have now. So if any of the variables it sets affect the functions like read_basic_state or finish_rebase (they don't currently appear to), then there's a potential for new bugs. That initial code would not previously have run in the --abort case at all.

But, you say the tests pass with those changes, so the changes are probably okay. However, they create a potential situation where some code is added to the top of one of the git-rebase--$type.sh scripts and suddenly git rebase --abort stops working right because that code is being run when it shouldn't or the operation of read_basic_state and/or finish_rebase is adversely affected. Hopefully the rebase tests would catch any such issue right away though.

So, in light of the fact that function nesting seems to be a non-issue here, and it seems to me the originally proposed changes have much less potential to introduce breakage either now or in the future, I still prefer them.

--Kyle
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel Development]     [Gcc Help]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [V4L]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]     [Fedora Users]