The test demonstrates that the behavior is undesirable right now: we move the
commit only past the update-ref todo of branch1, which means the order of
commits stays the same and only the branch head icon moves up by one. However,
we move the selection down by one, so the wrong commit is selected now. This is
especially bad if you type a bunch of ctrl-j quickly in a row, because now you
are moving the wrong commit.
There are two possible ways to fix this:
1) keep the moving behavior the same, but don't change the selection
2) change the behavior so that we move the commit not only past the update-ref,
but also past the next real commit.
You could argue that 1) is the more desirable fix, as it gives you more control
over where exactly the moved commit goes; however, it is much trickier to
implement, so we go with 2) for now (and that's what the commented-out
"EXPECTED" section documents here). If users need more fine-grained control,
they can always enter an interactive rebase first.
For non-merge commits we change "pick" to "drop" when we delete them. We do this
so that we can use the same code for dropping a commit no matter whether we are
in an interactive rebase or not. (If we aren't, we could just as well delete the
pick line from the todo list instead of setting it to "drop", but if we are, it
is better to keep the line around so that the user can change it back to "pick"
if they change their mind.)
However, merge commits can't be changed to "drop", so we have to delete them
from the todo file. We add a new daemon instruction that does this.
We still don't allow deleting a merge commit from within an interactive rebase.
The reason is that we don't show the "label" and "reset" todos in lazygit, so
deleting a merge commit would leave the commits from the branch that is being
merged in the list as "pick" commits, with no indication that they are going to
be dropped because they are on a different branch, and the merge commit that
would have brought them in is gone. This could be very confusing.
In 67b8ef449c we changed the "edit" command to insert a "break" after the
selected commit, rather than setting the selected todo to "edit". The reason for
doing this was that it now works for merge commits too.
Back then, I claimed "In most cases the behavior is exactly the same as before."
Unfortunately that's not true, there are two reasons why the previous behavior
was better (both are demonstrated by tests earlier in this branch):
- when editing the last commit of a branch in the middle of a stack of branches,
we are now missing the update-ref todo after it, which means that amending the
commit breaks the stack
- it breaks auto-amending (see the added test earlier in this branch for an
explanation)
For these reasons, we are going back to the previous approach of setting the
selected commit to "edit" whenever possible, i.e. unless it's a merge commit.
The only scenario where this could still be a problem is when you have a stack
of branches, and the last commit of one of the branches in the stack is a merge
commit, and you try to edit that. In my experience with stacked branches this is
very unlikely, in almost all cases my stacked branches are linear.
This is very similar to edit_range_select_outside_rebase.go, except that it
selects commits right after, and including, a merge commit.
This test already works correctly. The reason we add it is that we are going to
have two different implementations of the `e` command depending on whether the
last selected commit is a merge commit, and we want to make sure they both work
with a range selection.
Auto-amending is a little-known feature of git that is very convenient once you
know it: whenever you stop at a commit marked with `edit` in an interactive
rebase, you can make changes and stage them, and when you continue the rebase
they automatically get amended to the commit you had stopped at. This is so
convenient because making changes to a commit is one of the main reasons why you
edit a commit.
Unfortunately this currently doesn't work in lazygit because we don't actually
use `edit` to stop at the first commit (instead, we add a `break` todo after it,
which doesn't have the auto-amend functionality).
We'll improve this later in this branch.
Unfortunately it isn't possible to delete them. This would often be useful, but
our todo rewriting mechanisms rely on being able to find todos by some
identifier (hash for pick, ref for update-ref), and exec todos don't have a
unique identifier.
Put it into the individual menu items instead.
Again, this is necessary because we are going to add another entry to the menu
that is independent of the selected branch.
The rebase.updateRefs feature of git is very useful to rebase a stack of
branches and keep everything nicely stacked; however, it is usually in the way
when you make a copy of a branch and want to rebase it "away" from the original
branch in some way or other. For example, the original branch might sit on main,
and you want to rebase the copy onto devel to see if things still compile there.
Or you want to do some heavy history rewriting experiments on the copy, but keep
the original branch in case the experiments fail. Or you want to split a branch
in two because it contains two unrelated sets of changes; so you make a copy,
and drop half of the commits from the copy, then check out the original branch
and drop the other half of the commits from it.
In all these cases, git's updateRefs feature insists on moving the original
branch along with the copy in the first rebase that you make on the copy. I
think this is a bug in git, it should create update-ref todos only for branches
that point into the middle of your branch (because only then do they form a
stack), not when they point at the head (because then it's a copy). I had a long
discussion about this on the git mailing list [1], but people either don't agree
or don't care enough.
So we fix this on our side: whenever we start a rebase for whatever reason, be
it interactive, non-interactive, or behind-the-scenes, we drop any update-ref
todos that are at the very top of the todo list, which fixes all the
above-mentioned scenarios nicely.
I will admit that there's one scenario where git's behavior is the desired one,
and the fix in this PR makes it worse: when you create a new branch off of an
existing one, with the intention of creating a stack of branches, but before you
make the first commit on the new branch you realize some problem with the first
branch (e.g. a commit that needs to be reworded or dropped). It this case you do
want both branches to be affected by the change. In my experience this scenario
is much rarer than the other ones that I described above, and it's also much
easier to recover from: just check out the other branch again and hard-reset it
to the rebased one.
[1]
https://public-inbox.org/git/354f9fed-567f-42c8-9da9-148a5e223022@haller-berlin.de/
It is a bad idea to read a git-rebase-todo file, remove some update-ref todos,
and write it back out behind git's back. This will cause git to actually remove
the branches referenced by those update-ref todos when the rebase is continued.
The reason is that git remembers the refs affected by update-ref todos at the
beginning of the rebase, and remembers information about them in the file
.git/rebase-merge/update-refs. Then, whenever the user performs a "git rebase
--edit-todo" command, it updates that file based on whether update-ref todos
were added or removed by that edit. If we rewrite the git-rebase-todo file
behind git's back, this updating doesn't happen.
Fix this by not updating the git-rebase-todo file directly in this case, but
performing a "git rebase --edit-todo" command where we set ourselves as the
editor and change the file in there. This makes git update the bookkeeping
information properly.
Ideally we would use this method for all cases where we change the
git-rebase-todo file (e.g. moving todos up/down, or changing the type of a
todo); this would be cleaner because we wouldn't mess with git's private
implementation details. I tried this, but unfortunately it isn't fast enough.
Right now, moving a todo up or down takes between 1 and 2ms on my machine;
changing it to do a "git rebase --edit-todo" slows it down to over 100ms, which
is unacceptable.
In the test we simply removed the update-ref todo but didn't make any other
changes to the todos. This should really have kept everything the way it was,
including the other branch head. The fact that the star was gone was really
because of the bug that we are going to fix later in the branch.
Change the test so that it also makes a change before the update-ref todo; this
way we test that the star is gone because we deleted the update-ref, not because
of the bug.
To guard against the bug, we add another assertion for the branches view to test
that both branches are still there. This currently fails.
To support this, we turn the confirmation prompt of the "Create fixup commit"
command into a menu; creating a fixup commit is the first entry, so that
"shift-F, enter" behaves the same as before. But there are additional entries
for creating "amend!" commits, either with or without file changes. These make
it easy to reword commit messages of existing commits.
We have such a test already (squash_fixups_above_first_commit.go), but it can't
be used for what we want to check here, because it uses the first commit, and we
can't move down from there. So create a new one that basically does the same
thing, but for a commit in the middle. The focus of this new test is to check
how the selection behaves; as you can see, there is a problem both when creating
a fixup and when squashing fixups. We'll address these separately in the next
commits.
It starts a rebase on the bottom-most commit of the range, and sets all the
selected commits to "edit" (skipping merge commits, because they can't be
edited).
The additional branch head icon is more confusing than useful in this situation.
The update-ref entries show very clearly where the branch heads will go when
continuing the rebase; the information where the branch heads used to be before
the rebase is not really needed here, and just makes the display more confusing.
I'm not adding more tests here because the changes to the existing tests
demonstrate the change clearly enough.
To do that, change the "Apply fixup commits" command to show a menu with the two
choices "in current branch" and "above the selected commit"; we make "in current
branch" the default, as it's the more useful one most of the time, even though
it is a breaking change for those who are used to "shift-S enter" meaning
"squash above selected".
This adds a bunch of tooltips to keybindings and updates some keybinding descriptions (i.e. labels).
It's in preparation for displaying more keybindings on-screen (in the bottom right of the screen),
and so due in part to laziness it shortens some descriptions so that we don't need to manage both
a short and long description (for on-screen vs in-menu). Nonetheless I've added a ShortDescription
field for when we do want to have both a short and long description.
You'll notice that some keybindings I deemed unworthy of the options view have longer descriptions,
because I could get away with it.
This is useful if you want to move a range of commits, so you select them, and
then realize it's better to do it in an interactive rebase. Pressing 'i'
preserves the range now.
A common issue I have is that I want to move a commit from the top of my branch
all the way down to the first commit on the branch. To do that, I need to navigate
down to the first commit on my branch, press 'e' to start an interactive rebase,
then navigate back up to the top of the branch, then move my commit back down to
the base. This is annoying.
Similarly annoying is moving the commit one-by-one without explicitly starting
an interactive rebase, because then each individual step is its own rebase which
takes a while in aggregate.
This PR allows you to press 'i' from the commits view to start an interactive
rebase from an 'appropriate' base. By appropriate, we mean that we want to start
from the HEAD and stop when we reach the first merge commit or commit on the main
branch. This may end up including more commits than you need, but it doesn't make
a difference.
This fixes two minor problems with the prompts:
1. When pressing shift-A in the local commits view, it would first prompt
whether to stage all files, and then it would prompt whether to amend the
commit at all. This doesn't make sense, it needs to be the other way round.
2. When pressing shift-A on the head commit in an interactive rebase, we would
ask whether they want to amend the last commit, like when pressing shift-A in
the files view. While this is technically correct, the fact that we're
amending the head commit in this case is just an implementation detail, and
from the user's point of view it's better to use the same prompt as we do for
any other commit.
To fix these, we remove the confirmation panel from AmendHelper.AmendHead() and
instead add it at the two call sites, so that we have more control over this.
When editing a commit, the index of the current commit can change; for example,
when merge commits are involved, or when working with stacked branches where
"update-ref" commands may be added above the selected commit.
Reselect the current commit after pressing "e"; this requires doing the refresh
blocking on the main thread. (Another option that I considered was to use a
SYNC refresh, and then select the new line with an OnUIThread inside the Then
function. This also works, but results in a very visible lag.)
We want to mark all local branch heads with a "*" in the local commits panel, to
make it easier to see how branches are stacked onto each other. In order to not
confuse users with "*" markers that they don't understand, do this only for the
case where users actually use stacked branches; those users are likely not going
to be confused by the display. This means we want to filter out a few branch
heads that shouldn't get the marker: the current branch, any main branch, and
any old branch that has been merged to master already.
This test not only tests the correct handling and display of the updateRef
command, but also the visualization of branch heads in the commits panel. Since
we are about to change the behavior here, extend the test so that a master
commit is added (we don't want this to be visualized as a branch head), and then
a stack of two non-main branches. At the end of this branch we only want to
visualize the head commit of the first.
This test is almost identical to swap_in_rebase_with_conflict.go, except that it
sets the commit that will conflict to "edit".
This test is interesting because there's special code needed to determine
whether an "edit" command conflicted or not, i.e. whether to show the "confl"
entry. In this case we do. We have lots of other tests already that have "edit"
commands that don't conflict, so that's covered already.
When stopping in a rebase because of a conflict, it is nice to see the commit
that git is trying to apply. Create a fake todo entry labelled "conflict" for
this, and show the "<-- YOU ARE HERE ---" string for that one (in red) instead
of for the real current head.
