As discussed in #2900, the milliseconds are rarely useful, and it can
be confusing with different timezones because it makes harder to
compare timestamps.
I added an environment variable to control the timestamp in a
cross-platform way. I didn't document because it exists only for tests
(like `JJ_RANDOMNESS_SEED`).
Closes#2900
When an operation is missing and we recover the workspace, we create a
new working-copy commit on top of the desired working-copy commit (per
the available head operation). We then reset the working copy to an
empty tree because it shouldn't really matter much which commit we
reset to. However, when the workspace is sparse, it does matter, as
the test case from the previous patch shows. This patch fixes it by
replacing the `reset_to_empty()` method by a new `recover(&Commit)`,
which effectively resets to the empty tree and then resets to the
commit. That way, any subsequent snapshotting will result keep the
paths from that tree for paths outside the sparse patterns.
As shown by the updated test case, when we recover from a working copy
pointing to a lost operation, the new working-copy commit after
snapshotting will have lost any files outside the sparse patterns.
We haven't used custom Git commit headers for two main reasons:
1. I don't want commits created by jj to be different from any other
commits. I don't want Git projects to get annoyed by such commit
and reject them.
2. I've been concerned that tools don't know how to handle such
headers, perhaps even resulting in crashes.
The first argument doesn't apply to commits with conflicts because
such commits would never be accepted by a project whether or not they
use custom commit headers. The second argument is less relevant for
conflicted commits because most tools will be confused by such commits
anyway.
Storing conflict information in commit headers means that we can
transfer them via the regular Git wire protocol. We already include
the tree objects nested inside the root-level tree, so they will also
be transferred.
So, let's start by writing the information redundantly to the commit
header and to the existing storage. That way we can roll it back if we
realize there's a problem with using commit headers.
The recovery commit we create when we run into a stale working copy
with a missing operation currently has an empty tree. Our commit
backend at Google creates an index of which files changed in each
commit. That gets really expensive when a commit deletes all files in
the repo, as these recovery commits do. So for our backend, it is much
better to make the recovery commit empty instead. That's what this
patch does.
It almost doesn't matter functionally what tree we use for it since we
don't care much about the current tree when snapshotting the working
copy. It does matter in a few cases, however. One case is for
conflicts. In that case, it's likely better to use the recovery
commit's parent as base tree (as we do by making the recovery commit
empty) than to use an empty tree, as that would guarantee that all
conflicts would be considered resolved. (Side note: perhaps we should
start looking at the current commit's parent instead of looking at the
current commit when snapshotting, but that's a topic for another day.)
It should be useful at least in the presentation layer to know which
operations correspond to working-copy snapshots. They might be
rendered differently in the graph, for example. Or maybe an undo
command wants to warn if you just undid a snapshot operation. This
patch just introduces a field in the metadata to store the
information.
When adding a new workspace, I would expect that it inherits the
patterns from the workspace I ran the command in. We currently don't
do that. That's quite annoying when your repo has very many files
(like at Google).
The `ContentHash` documentation specifies that implementations for enums should
hash the ordinal number of the variant contained in the enum as a 32-bit
little-endian number and then hash the contents of the variant, if any.
The current implementations for `std::Option`, `MergedTreeId`, and
`RemoteRefState` are non-conformant since they hash the ordinal number as a u8
with platform specific endianness.
Fixes#3051
If the operation corresponding to a workspace is missing for some reason
(the specific situation in the test in this commit is that an operation
was abandoned and garbage-collected from another workspace), currently,
jj fails with a 255 error code. Teach jj a way to recover from this
situation.
When jj detects such a situation, it prints a message and stops
operation, similar to when a workspace is stale. The message tells the
user what command to run.
When that command is run, jj loads the repo at the @ operation (instead
of the operation of the workspace), creates a new commit on the @
commit with an empty tree, and then proceeds as usual - in particular,
including the auto-snapshotting of the working tree, which creates
another commit that obsoletes the newly created commit.
There are several design points I considered.
1) Whether the recovery should be automatic, or (as in this commit)
manual in that the user should be prompted to run a command. The user
might prefer to recover in another way (e.g. by simply deleting the
workspace) and this situation is (hopefully) rare enough that I think
it's better to prompt the user.
2) Which command the user should be prompted to run (and thus, which
command should be taught to perform the recovery). I chose "workspace
update-stale" because the circumstances are very similar to it: it's
symptom is that the regular jj operation is blocked somewhere at the
beginning, and "workspace update-stale" already does some special work
before the blockage (this commit adds more of such special work). But it
might be better for something more explicitly named, or even a sequence
of commands (e.g. "create a new operation that becomes @ that no
workspace points to", "low-level command that makes a workspace point to
the operation @") but I can see how this can be unnecessarily confusing
for the user.
3) How we recover. I can think of several ways:
a) Always create a commit, and allow the automatic snapshotting to
create another commit that obsoletes this commit.
b) Create a commit but somehow teach the automatic snapshotting to
replace the created commit in-place (so it has no predecessor, as viewed
in "obslog").
c) Do either a) or b), with the added improvement that if there is no
diff between the newly created commit and the former @, to behave as if
no new commit was created (@ remains as the former @).
I chose a) since it was the simplest and most easily reasoned about,
which I think is the best way to go when recovering from a rare
situation.
this greatly speeds up the time to run all tests, at the cost of slightly larger recompile times for individual tests.
this unfortunately adds the requirement that all tests are listed in `runner.rs` for the crate.
to avoid forgetting, i've added a new test that ensures the directory is in sync with the file.
## benchmarks
before this change, recompiling all tests took 32-50 seconds and running a single test took 3.5 seconds:
```
; hyperfine 'touch lib/src/lib.rs && cargo t --test test_working_copy'
Time (mean ± σ): 3.543 s ± 0.168 s [User: 2.597 s, System: 1.262 s]
Range (min … max): 3.400 s … 3.847 s 10 runs
```
after this change, recompiling all tests take 4 seconds:
```
; hyperfine 'touch lib/src/lib.rs ; cargo t --test runner --no-run'
Time (mean ± σ): 4.055 s ± 0.123 s [User: 3.591 s, System: 1.593 s]
Range (min … max): 3.804 s … 4.159 s 10 runs
```
and running a single test takes about the same:
```
; hyperfine 'touch lib/src/lib.rs && cargo t --test runner -- test_working_copy'
Time (mean ± σ): 4.129 s ± 0.120 s [User: 3.636 s, System: 1.593 s]
Range (min … max): 3.933 s … 4.346 s 10 runs
```
about 1.4 seconds of that is the time for the runner, of which .4 is the time for the linker. so
there may be room for further improving the times.
It seems obvious in hindsight to have a virtual root operation just
like we have a virtual root commit. It removes the same kind of
problems by making sure there's always a common ancestor (or multiple)
between any two commits.
I think the reason I didn't add a root operation from the beginning
was that there used to be a mandatory working-copy commit in the view
(this was before support for multiple workspaces).
Perhaps we should remove the "initialize repo" operation now. The only
difference between their view objects is that the "initialize repo"
operation adds the root commit as a head. We could add that to the
root operation, but then the root operation's value depends on the
commit backend.
We've had the public_heads for as long as we've had the View object,
IIRC (I didn't check), but we still don't use it for anything. I don't
have any concrete plans for using it either. Maybe our config for
immutable commits is good enough, or maybe we'll want something more
generic (like Mercurial's phases). For now, I think we should simplify
by removing it the storage for public heads.
Summary: A natural extension of the existing support, as suggested by Scott
Olson. Closes#2496.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Change-Id: I91c9c8c377ad67ccde7945ed41af6c79
Summary: Yuya's changes and mine had a semantic conflict ("merge skew") between
the two of them, as b7c7b19e changed the `op log `output slightly, whereas
220292ad included a new test that used `op log` itself.
Generated by `cargo insta review`.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Change-Id: I51d4de7316b1abc09be4f9fa0dd0d1a1
There's a subtle behavior change. Unlike the original remove_remote_branch(),
remote_views entry is not discarded when the branches map becomes empty. The
reasoning here is that the remote view can be added/removed when the remote
is added/removed respectively, though that's not implemented yet. Since the
serialized data cannot represent an empty remote, such view may generate
non-unique content hash.
Summary: This allows `workspace forget` to forget multiple workspaces in a
single action; it now behaves more consistently with other verbs like `abandon`
which can take multiple revisions at one time.
There's some hoop-jumping involved to ensure the oplog transaction description
looks nice, but as they say: small conveniences cost a lot.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Change-Id: Id91da269f87b145010c870b7dc043748
Summary: Workspaces are most useful to test different versions (commits) of
the tree within the same repository, but in many cases you want to check out a
specific commit within a workspace.
Make that trivial with a `--revision` option which will be used as the basis
for the new workspace. If no `-r` option is given, then the previous behavior
applies: the workspace is created with a working copy commit created on top of
the current working copy commit's parent.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Change-Id: I23549efe29bc23fb9f75437b6023c237
I have used the tree-level conflict format for several weeks without
problem (after the fix in 51b5d168ae). Now - right after the 0.10.0
release - seems like a good time to enable the config by default.
I enabled the config in our default configs in the CLI crate to reduce
impact on tests (compared to changing the default in `settings.rs`).
We resolve file paths into repo-relative paths while parsing the
revset expression, so I think it's consistent to also resolve which
workspace "@" refers to while parsing it. That means we won't need the
workspace context both while parsing and while resolving symbols.
In order to break things like `author("martinvonz@")` (thanks to @yuja
for catching this), I also changed the parsing of working-copy
expressions so they are not allowed to be
quoted. `author(martinvonz@)` will therefore be an error now. That
seems like a small improvement anyway, since we have recently talked
about making `root` and `[workspace]@` not parsed as other symbols.
