ilyagr.bsky.social
commits
This is useful to see which merges resolve conflicts and to more easily
sort WIP commits.
Some ideas I thought about and decided against:
- `∅` looked too messy
- I considered using green for "empty", and yellow for "non-empty
working copy", but I think the dotted circle is visible enough and
making the working copy stand out is more important.
- There's the option of using `○` for empty commits and `●` for
non-empty, but I personally feel like so many `●`s would look too heavy.
This avoids an MkDocs warning.
I put it into Design Docs, since people who follow the link to the
roadmap might be interested in those.
It's not a perfect place for it, but it seems better than "Technical
Details" or "Contributing" (which might make people think that they have
to read or follow the roadmap before contributing).
This should help a bit when merging files using a high-latency
backend.
This just propagates the async a little bit futher where it's easy to
do so.
This doesn't provide any benefit yet bit I think we've known for a
while that we want to make the backend write methods async. It's just
not been important to Google because we have the local daemon process
that makes our writes pretty fast. Regardless, this first commit just
changes the API and all callers immediately block for now, so it won't
help even on slow backends.
The roadmap seems like something users might want to read soon after
they find the project, so a link from the main page seems useful to
me.
When building this project with [Nix/Crane](https://github.com/ipetkov/crane/discussions/693), if the `jj-cli` dependency is specified in `Cargo.toml` as a git-based crate, `cargo vendor` splits this workspace up into sub-crate directories, which causes `cargo metadata` to fail when searching for relative deps in the workspace root.
This commit simply changes how the crate version is determined, using Cargo's built-in environment variable [`CARGO_PKG_VERSION`](https://doc.rust-lang.org/cargo/reference/environment-variables.html)
MkDocs did not render this list in
https://martinvonz.github.io/jj/prerelease/config/#node-style properly
before.
I don't understand the reason; we have other lists that are formatted
similarly to how this one was, and they look fine in MkDocs. This might
be a bug in one of the MkDocs extensions for lists that we use.
Right now, renamed and copied files don't have any color in the output
of `jj status`, and it makes them stand out. I think it's reasonable to
color renamed files the same as modified files, since renaming is like
modifying the path, and to color copied files the same as added files,
since they're basically just added files that happen to have similar
contents to an existing file.
The question "How do I avoid committing changes to files?" comes up a lot in
chat, and the solution is not obvious. It will be useful to have a description
with an example we can link to.
The wording of the similar question "How can I keep my scratch files in the
repository?" was tweaked to emphasize the difference between keeping untracked
files in the workspace and keeping changes tracked files out of published
history.
Bumps the cargo-dependencies group with 1 update: [whoami](https://github.com/ardaku/whoami).
Updates `whoami` from 1.5.1 to 1.5.2
- [Changelog](https://github.com/ardaku/whoami/blob/v1/CHANGELOG.md)
- [Commits](https://github.com/ardaku/whoami/compare/v1.5.1...v1.5.2)
---
updated-dependencies:
- dependency-name: whoami
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
This avoids cloning `UserSettings` and some other data. I haven't
attempted to measure the performance impact (I expect it's tiny); this
is more about clarifying that there are not multiple different
versions of these fields.
This wraps all the fields in `CommandHelper` in an `Rc` so
`CommandHelper` itself becomes cheap to clone (thanks to @yuja for the
idea). I'll use that next to avoid some cloning in
`WorkspaceCommandHelper`.
Bumps the github-dependencies group with 1 update: [actions/upload-artifact](https://github.com/actions/upload-artifact).
Updates `actions/upload-artifact` from 4.3.6 to 4.4.0
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/834a144ee995460fba8ed112a2fc961b36a5ec5a...50769540e7f4bd5e21e526ee35c689e35e0d6874)
---
updated-dependencies:
- dependency-name: actions/upload-artifact
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: github-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the cargo-dependencies group with 3 updates: [async-trait](https://github.com/dtolnay/async-trait), [indexmap](https://github.com/indexmap-rs/indexmap) and [syn](https://github.com/dtolnay/syn).
Updates `async-trait` from 0.1.81 to 0.1.82
- [Release notes](https://github.com/dtolnay/async-trait/releases)
- [Commits](https://github.com/dtolnay/async-trait/compare/0.1.81...0.1.82)
Updates `indexmap` from 2.4.0 to 2.5.0
- [Changelog](https://github.com/indexmap-rs/indexmap/blob/master/RELEASES.md)
- [Commits](https://github.com/indexmap-rs/indexmap/compare/2.4.0...2.5.0)
Updates `syn` from 2.0.76 to 2.0.77
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/2.0.76...2.0.77)
---
updated-dependencies:
- dependency-name: async-trait
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
- dependency-name: indexmap
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: cargo-dependencies
- dependency-name: syn
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
This helps resolve diverged refs by abandoning both sides:
D ref = [D]
|\
| C C ref = [B - D + C]
| | |
B | B | B ref = [B - D + A]
|/ |/ |
A A A A ref = [A - D + A]
This is stricter than from_legacy_from() in that wrong number of add/remove
terms will panic.
It no longer makes sense to look up branches by old_commit_id. Just loop over
branch (name, target) pairs instead.
We have not used libgit2 for gitignores since commit 88f7f473
(2021-05-13).
This was quadratic before, and was super slow if thousands of commits were
abandoned.
#4352
This is closer to the original behavior before 5e8d7f8c "rewrite: update
references after rewriting all commits." References can move to divergent
commits, so they should propagate further if there are more rewrites. See
the inline comment for subtle behavior difference.
We could instead replay parent_mapping in topological order, but we would
still need to flatten abandon records.
I'll use this in debug assertion. The extracted function is not named as
new_parents_with() because it's not really about parents.
"Concurrent" operations are not necessarily actually concurrent, so
"divergent" seems like a better name. And "reconcile" seems like a
better term for merging them, though we also sometimes use "merge".
Like https://github.com/martinvonz/jj/pull/4189, this allows extensions the ability to load the repo in an environment where the local filesystem is not accessible. This change allows such extensions to exist at the CLI layer where jj is invoked as a subprocess, rather than a library (common in testing).
Bumps the cargo-dependencies group with 1 update: [tokio](https://github.com/tokio-rs/tokio).
Updates `tokio` from 1.39.3 to 1.40.0
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](https://github.com/tokio-rs/tokio/compare/tokio-1.39.3...tokio-1.40.0)
---
updated-dependencies:
- dependency-name: tokio
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the github-dependencies group with 2 updates: [actions/setup-python](https://github.com/actions/setup-python) and [github/codeql-action](https://github.com/github/codeql-action).
Updates `actions/setup-python` from 5.1.1 to 5.2.0
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/compare/39cd14951b08e74b54015e9e001cdefcf80e669f...f677139bbe7f9c59b41e40162b753c062f5d49a3)
Updates `github/codeql-action` from 3.26.5 to 3.26.6
- [Release notes](https://github.com/github/codeql-action/releases)
- [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
- [Commits](https://github.com/github/codeql-action/compare/2c779ab0d087cd7fe7b826087247c2c81f27bfa6...4dd16135b69a43b6c8efb853346f8437d92d3c93)
---
updated-dependencies:
- dependency-name: actions/setup-python
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: github-dependencies
- dependency-name: github/codeql-action
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: github-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
I just choose "clru" because it already exists in our dependency tree thorough
gix. I don't think LRU is the best cache eviction policy for our use case (a
simpler FIFO-based one might be good enough?), but it wouldn't matter for CLI
or GUI use case. I don't see significant performance degradation with "jj log
--stat -n1000".
RwLock is replaced with Mutex since get() is inherently a mutable operation.
If merge-heavy history was abandoned, intermediate parent chains can have tons
of duplicates, and the process explodes soon. Instead, we can skip any parent
ids that have been remapped.
We can no longer detect cycles reliably, but I think that's okay so long as
the function terminates.
Fixes #4352
This is basically a DFS to find leaf nodes. It will help omit duplicated
parent ids early.
Bumps the cargo-dependencies group with 1 update: [rustix](https://github.com/bytecodealliance/rustix).
Updates `rustix` from 0.38.34 to 0.38.35
- [Release notes](https://github.com/bytecodealliance/rustix/releases)
- [Commits](https://github.com/bytecodealliance/rustix/compare/v0.38.34...v0.38.35)
---
updated-dependencies:
- dependency-name: rustix
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
I played with max-inline-alternation = 3 for a couple of weeks, and it's pretty
good. I think somewhere between 2 and 4 is good default because one or two
remove + add sequences are easy to parse.
We haven't decided how conflict diffs should be rendered, but whatever style
we'll choose, we'll need raw unmaterialized conflict contents.
FileConflict will be changed to not materialize Merge<BString>. I also updated
the revset engine to ignore non-file conflict. It doesn't make sense to grep
conflict description.
I'll add more callers of id.describe(), and the output size wouldn't be large
enough to avoid allocation by using Write API.
ContentHunk is basically a nice wrapper around Vec<u8>. I think it would give
little benefit for type safety.
Bumps the cargo-dependencies group with 1 update: [clap_complete](https://github.com/clap-rs/clap).
Updates `clap_complete` from 4.5.23 to 4.5.24
- [Release notes](https://github.com/clap-rs/clap/releases)
- [Changelog](https://github.com/clap-rs/clap/blob/master/CHANGELOG.md)
- [Commits](https://github.com/clap-rs/clap/compare/clap_complete-v4.5.23...clap_complete-v4.5.24)
---
updated-dependencies:
- dependency-name: clap_complete
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the cargo-dependencies group with 3 updates: [serde](https://github.com/serde-rs/serde), [serde_json](https://github.com/serde-rs/json) and [syn](https://github.com/dtolnay/syn).
Updates `serde` from 1.0.208 to 1.0.209
- [Release notes](https://github.com/serde-rs/serde/releases)
- [Commits](https://github.com/serde-rs/serde/compare/v1.0.208...v1.0.209)
Updates `serde_json` from 1.0.125 to 1.0.127
- [Release notes](https://github.com/serde-rs/json/releases)
- [Commits](https://github.com/serde-rs/json/compare/1.0.125...1.0.127)
Updates `syn` from 2.0.75 to 2.0.76
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/2.0.75...2.0.76)
---
updated-dependencies:
- dependency-name: serde
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
- dependency-name: serde_json
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
- dependency-name: syn
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the github-dependencies group with 1 update: [github/codeql-action](https://github.com/github/codeql-action).
Updates `github/codeql-action` from 3.26.4 to 3.26.5
- [Release notes](https://github.com/github/codeql-action/releases)
- [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
- [Commits](https://github.com/github/codeql-action/compare/f0f3afee809481da311ca3a6ff1ff51d81dbeb24...2c779ab0d087cd7fe7b826087247c2c81f27bfa6)
---
updated-dependencies:
- dependency-name: github/codeql-action
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: github-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Useful for third party tools to override, along with the version.
Signed-off-by: Austin Seipp <aseipp@pobox.com>
I don't think "jj untrack" is frequently used, and I think it is a "file"
command rather than "workspace".
It's been enabled since 8fec7500c32a "cli: enable fileset by default."
If movement commands don't find a target commit, they fail. However,
it's usually not intuitive why they fail because in non-edit mode the
start commit is the parent of the working commit.
Adding the start commit change hash to the error message makes it easier
for the user to figure out what is going on.
Also, specifying 'No **other** descendant...' helps make it clear what
`jj` is really looking for.
Part of #3947
Since only `--name-only` doesn't support copies/renames, it's simpler
to say that than to list the formats that do.
The native backend currently errors out if you ask it about copies. So
does the test backend. I think it's better to return an empty stream
of copies so it doesn't prevent other functionality.
This came up in #4323.
This is useful to see which merges resolve conflicts and to more easily
sort WIP commits.
Some ideas I thought about and decided against:
- `∅` looked too messy
- I considered using green for "empty", and yellow for "non-empty
working copy", but I think the dotted circle is visible enough and
making the working copy stand out is more important.
- There's the option of using `○` for empty commits and `●` for
non-empty, but I personally feel like so many `●`s would look too heavy.
This avoids an MkDocs warning.
I put it into Design Docs, since people who follow the link to the
roadmap might be interested in those.
It's not a perfect place for it, but it seems better than "Technical
Details" or "Contributing" (which might make people think that they have
to read or follow the roadmap before contributing).
This doesn't provide any benefit yet bit I think we've known for a
while that we want to make the backend write methods async. It's just
not been important to Google because we have the local daemon process
that makes our writes pretty fast. Regardless, this first commit just
changes the API and all callers immediately block for now, so it won't
help even on slow backends.
When building this project with [Nix/Crane](https://github.com/ipetkov/crane/discussions/693), if the `jj-cli` dependency is specified in `Cargo.toml` as a git-based crate, `cargo vendor` splits this workspace up into sub-crate directories, which causes `cargo metadata` to fail when searching for relative deps in the workspace root.
This commit simply changes how the crate version is determined, using Cargo's built-in environment variable [`CARGO_PKG_VERSION`](https://doc.rust-lang.org/cargo/reference/environment-variables.html)
MkDocs did not render this list in
https://martinvonz.github.io/jj/prerelease/config/#node-style properly
before.
I don't understand the reason; we have other lists that are formatted
similarly to how this one was, and they look fine in MkDocs. This might
be a bug in one of the MkDocs extensions for lists that we use.
Right now, renamed and copied files don't have any color in the output
of `jj status`, and it makes them stand out. I think it's reasonable to
color renamed files the same as modified files, since renaming is like
modifying the path, and to color copied files the same as added files,
since they're basically just added files that happen to have similar
contents to an existing file.
The question "How do I avoid committing changes to files?" comes up a lot in
chat, and the solution is not obvious. It will be useful to have a description
with an example we can link to.
The wording of the similar question "How can I keep my scratch files in the
repository?" was tweaked to emphasize the difference between keeping untracked
files in the workspace and keeping changes tracked files out of published
history.
Bumps the cargo-dependencies group with 1 update: [whoami](https://github.com/ardaku/whoami).
Updates `whoami` from 1.5.1 to 1.5.2
- [Changelog](https://github.com/ardaku/whoami/blob/v1/CHANGELOG.md)
- [Commits](https://github.com/ardaku/whoami/compare/v1.5.1...v1.5.2)
---
updated-dependencies:
- dependency-name: whoami
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the github-dependencies group with 1 update: [actions/upload-artifact](https://github.com/actions/upload-artifact).
Updates `actions/upload-artifact` from 4.3.6 to 4.4.0
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/834a144ee995460fba8ed112a2fc961b36a5ec5a...50769540e7f4bd5e21e526ee35c689e35e0d6874)
---
updated-dependencies:
- dependency-name: actions/upload-artifact
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: github-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the cargo-dependencies group with 3 updates: [async-trait](https://github.com/dtolnay/async-trait), [indexmap](https://github.com/indexmap-rs/indexmap) and [syn](https://github.com/dtolnay/syn).
Updates `async-trait` from 0.1.81 to 0.1.82
- [Release notes](https://github.com/dtolnay/async-trait/releases)
- [Commits](https://github.com/dtolnay/async-trait/compare/0.1.81...0.1.82)
Updates `indexmap` from 2.4.0 to 2.5.0
- [Changelog](https://github.com/indexmap-rs/indexmap/blob/master/RELEASES.md)
- [Commits](https://github.com/indexmap-rs/indexmap/compare/2.4.0...2.5.0)
Updates `syn` from 2.0.76 to 2.0.77
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/2.0.76...2.0.77)
---
updated-dependencies:
- dependency-name: async-trait
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
- dependency-name: indexmap
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: cargo-dependencies
- dependency-name: syn
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
This is closer to the original behavior before 5e8d7f8c "rewrite: update
references after rewriting all commits." References can move to divergent
commits, so they should propagate further if there are more rewrites. See
the inline comment for subtle behavior difference.
We could instead replay parent_mapping in topological order, but we would
still need to flatten abandon records.
Like https://github.com/martinvonz/jj/pull/4189, this allows extensions the ability to load the repo in an environment where the local filesystem is not accessible. This change allows such extensions to exist at the CLI layer where jj is invoked as a subprocess, rather than a library (common in testing).
Bumps the cargo-dependencies group with 1 update: [tokio](https://github.com/tokio-rs/tokio).
Updates `tokio` from 1.39.3 to 1.40.0
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](https://github.com/tokio-rs/tokio/compare/tokio-1.39.3...tokio-1.40.0)
---
updated-dependencies:
- dependency-name: tokio
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the github-dependencies group with 2 updates: [actions/setup-python](https://github.com/actions/setup-python) and [github/codeql-action](https://github.com/github/codeql-action).
Updates `actions/setup-python` from 5.1.1 to 5.2.0
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/compare/39cd14951b08e74b54015e9e001cdefcf80e669f...f677139bbe7f9c59b41e40162b753c062f5d49a3)
Updates `github/codeql-action` from 3.26.5 to 3.26.6
- [Release notes](https://github.com/github/codeql-action/releases)
- [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
- [Commits](https://github.com/github/codeql-action/compare/2c779ab0d087cd7fe7b826087247c2c81f27bfa6...4dd16135b69a43b6c8efb853346f8437d92d3c93)
---
updated-dependencies:
- dependency-name: actions/setup-python
dependency-type: direct:production
update-type: version-update:semver-minor
dependency-group: github-dependencies
- dependency-name: github/codeql-action
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: github-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
I just choose "clru" because it already exists in our dependency tree thorough
gix. I don't think LRU is the best cache eviction policy for our use case (a
simpler FIFO-based one might be good enough?), but it wouldn't matter for CLI
or GUI use case. I don't see significant performance degradation with "jj log
--stat -n1000".
RwLock is replaced with Mutex since get() is inherently a mutable operation.
Bumps the cargo-dependencies group with 1 update: [rustix](https://github.com/bytecodealliance/rustix).
Updates `rustix` from 0.38.34 to 0.38.35
- [Release notes](https://github.com/bytecodealliance/rustix/releases)
- [Commits](https://github.com/bytecodealliance/rustix/compare/v0.38.34...v0.38.35)
---
updated-dependencies:
- dependency-name: rustix
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the cargo-dependencies group with 1 update: [clap_complete](https://github.com/clap-rs/clap).
Updates `clap_complete` from 4.5.23 to 4.5.24
- [Release notes](https://github.com/clap-rs/clap/releases)
- [Changelog](https://github.com/clap-rs/clap/blob/master/CHANGELOG.md)
- [Commits](https://github.com/clap-rs/clap/compare/clap_complete-v4.5.23...clap_complete-v4.5.24)
---
updated-dependencies:
- dependency-name: clap_complete
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the cargo-dependencies group with 3 updates: [serde](https://github.com/serde-rs/serde), [serde_json](https://github.com/serde-rs/json) and [syn](https://github.com/dtolnay/syn).
Updates `serde` from 1.0.208 to 1.0.209
- [Release notes](https://github.com/serde-rs/serde/releases)
- [Commits](https://github.com/serde-rs/serde/compare/v1.0.208...v1.0.209)
Updates `serde_json` from 1.0.125 to 1.0.127
- [Release notes](https://github.com/serde-rs/json/releases)
- [Commits](https://github.com/serde-rs/json/compare/1.0.125...1.0.127)
Updates `syn` from 2.0.75 to 2.0.76
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](https://github.com/dtolnay/syn/compare/2.0.75...2.0.76)
---
updated-dependencies:
- dependency-name: serde
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
- dependency-name: serde_json
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
- dependency-name: syn
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: cargo-dependencies
...
Signed-off-by: dependabot[bot] <support@github.com>
Bumps the github-dependencies group with 1 update: [github/codeql-action](https://github.com/github/codeql-action).
Updates `github/codeql-action` from 3.26.4 to 3.26.5
- [Release notes](https://github.com/github/codeql-action/releases)
- [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
- [Commits](https://github.com/github/codeql-action/compare/f0f3afee809481da311ca3a6ff1ff51d81dbeb24...2c779ab0d087cd7fe7b826087247c2c81f27bfa6)
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updated-dependencies:
- dependency-name: github/codeql-action
dependency-type: direct:production
update-type: version-update:semver-patch
dependency-group: github-dependencies
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Signed-off-by: dependabot[bot] <support@github.com>
If movement commands don't find a target commit, they fail. However,
it's usually not intuitive why they fail because in non-edit mode the
start commit is the parent of the working commit.
Adding the start commit change hash to the error message makes it easier
for the user to figure out what is going on.
Also, specifying 'No **other** descendant...' helps make it clear what
`jj` is really looking for.
Part of #3947