Follows up 7552f939c6 "tests: disable most gpg integration tests on Windows."
I couldn't find this test failing in a few samples before, but it does now.
This removes the special handling of the working-copy commit. By
recording when an empty/emptied commit was abanoned, we rebase
descendants correctly and create a new empty working-copy commit on
top.
This partially reverts changes in a9f489ccdf "Switch to ignore crate for
gitignore handling." Since child ignore object no longer needs to access the
root to resolve the prefix path, it's simpler to store a matcher per node.
With the current implementation, the file3 pattern is set to the prefix
"foo/foo/bar". I don't know if (unrooted) "baz" prefixed with "foo/foo/bar"
should match "foo/bar/baz", but apparently it is. Anyway, that wouldn't be
the case in practice because adjacent .gitignore files shouldn't be loaded.
We do clone Operation object in several places, and I'm going to add one more
.clone() in the templater. Since the underlying metadata has many fields, I
think it's better to wrap it with Arc just like a Commit object.
The default immutable_heads() includes tags(), which makes sense, but computing
heads(tags()) can be expensive because the tags() set is usually sparse. For
example, "jj bench revset 'heads(tags())'" took 157ms in my linux stable
mirror. We can of course optimize the heads evaluation by using bit set or
segmented index, but the query includes many historical heads if the repository
has per-release branches, which are uninteresting anyway. So, this patch
replaces heads(immutable_heads()) with trunk().
The reason we include heads(immutable_heads()) is to mitigate the following
problem. Suppose trunk() is the branch to be based off, I think using trunk()
here is pretty good.
```
A B
*---*----* trunk() ⊆ immutable_heads()
\
* C
```
https://github.com/martinvonz/jj/pull/2247#discussion_r1335078879
In my linux stable mirror, this makes the default log revset evaluation super
fast. immutable_heads(), if configured properly, includes many historical
branch heads which are also the visible heads.
revsets/immutable_heads()..
---------------------------
0 12.27 117.1±0.77m
3 1.00 9.5±0.08m
I'm going to add pre-filtering to the 'roots..heads' evaluation path, and
difference_by() will be used there to calculate 'heads ~ roots'.
Union and intersection iterators are slightly changed so that all iterators
prioritize iter1's item.
This adds a guard to the gpg signing tests which will skip the test if
`gpg` is not installed on the system.
This is done in order to avoid requiring all collaborators to have setup
all the tools on their local machines that are required to test commit
signing.
When doing things like testing snapshot performance differences,
this allows you to turn off the monitor, no matter what the enabled
user or repository configuration has, e.g.
jj st --config-toml='core.fsmonitor="none"'
Signed-off-by: Austin Seipp <aseipp@pobox.com>
Consider this code:
```
struct NoContentHash {}
#[derive(ContentHash)]
enum Hashable {
NoCanHash(NoContentHash),
Empty,
}
```
Before this commit, it generates an error like this:
```
error[E0277]: the trait bound `NoContentHash: ContentHash` is not satisfied
--> lib/src/content_hash.rs:150:10
|
150 | #[derive(ContentHash)]
| ^^^^^^^^^^^ the trait `ContentHash` is not implemented for `NoContentHash`
151 | enum Hashable {
152 | NoCanHash(NoContentHash),
| --------- required by a bound introduced by this call
|
= help: the following other types implement trait `ContentHash`:
bool
i32
i64
u8
u32
u64
std::collections::HashMap<K, V>
BTreeMap<K, V>
and 35 others
For more information about this error, try `rustc --explain E0277`.
```
After this commit, it generates a better error message:
```
error[E0277]: the trait bound `NoContentHash: ContentHash` is not satisfied
--> lib/src/content_hash.rs:152:15
|
152 | NoCanHash(NoContentHash),
| ^^^^^^^^^^^^^ the trait `ContentHash` is not implemented for `NoContentHash`
|
= help: the following other types implement trait `ContentHash`:
bool
i32
i64
u8
u32
u64
std::collections::HashMap<K, V>
BTreeMap<K, V>
and 35 others
For more information about this error, try `rustc --explain E0277`.
error: could not compile `jj-lib` (lib) due to 1 previous error
```
It also works for enum variants with named fields:
```
error[E0277]: the trait bound `NoContentHash: ContentHash` is not satisfied
--> lib/src/content_hash.rs:152:23
|
152 | NoCanHash { named: NoContentHash },
| ^^^^^^^^^^^^^ the trait `ContentHash` is not implemented for `NoContentHash`
|
= help: the following other types implement trait `ContentHash`:
bool
i32
i64
u8
u32
u64
std::collections::HashMap<K, V>
BTreeMap<K, V>
and 35 others
For more information about this error, try `rustc --explain E0277`.
```
This is a no-op in terms of function, but provides a nicer way to derive the
ContentHash trait for structs using the `#[derive(ContentHash)]` syntax used
for other traits such as `Debug`.
This commit only adds the macro. A subsequent commit will replace uses of
`content_hash!{}` with `#[derive(ContentHash)]`.
The new macro generates nice error messages, just like the old macro:
```
error[E0277]: the trait bound `NotImplemented: content_hash::ContentHash` is not satisfied
--> lib/src/content_hash.rs:265:16
|
265 | z: NotImplemented,
| ^^^^^^^^^^^^^^ the trait `content_hash::ContentHash` is not implemented for `NotImplemented`
|
= help: the following other types implement trait `content_hash::ContentHash`:
bool
i32
i64
u8
u32
u64
std::collections::HashMap<K, V>
BTreeMap<K, V>
and 38 others
```
This commit does two things to make proc macros re-exported by jj_lib useable
by deps:
1. jj_lib needs to be able refer to itself as `jj_lib` which it does
by adding an `extern crate self as jj_lib` declaration.
2. jj_lib::content_hash needs to re-export the `digest::Update` type so that
users of jj_lib can use the `#[derive(ContentHash)]` proc macro without
directly depending on the digest crate. This is done by re-exporting it
as `DigestUpdate`.
#3054
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.
I think the conclusion from #2600 is that at least auto-rebasing
should not simplify merge commits that merge a commit with its
ancestor. Let's start by adding an option for that in the library.
The shortest change id prefix will become a few digits longer, but I think
that's acceptable. Entries included in the "revsets.short-prefixes" set are
unaffected.
The reachable set is calculated eagerly, but this is still faster as we no
longer need to sort the reachable entries by change id. The lazy version will
save another ~100ms in mid-size repos.
"jj log" without working copy snapshot:
```
% hyperfine --sort command --warmup 3 --runs 20 -L bin jj-0,jj-1,jj-2 \
-s "target/release-with-debug/{bin} -R ~/mirrors/linux debug reindex" \
"target/release-with-debug/{bin} -R ~/mirrors/linux \
--ignore-working-copy log -r.. -l100 --config-toml='revsets.short-prefixes=\"\"'"
Benchmark 1: target/release-with-debug/jj-0 -R ~/mirrors/linux --ignore-working-copy log -r.. -l100 --config-toml='revsets.short-prefixes=""'
Time (mean ± σ): 353.6 ms ± 11.9 ms [User: 266.7 ms, System: 87.0 ms]
Range (min … max): 329.0 ms … 365.6 ms 20 runs
Benchmark 2: target/release-with-debug/jj-1 -R ~/mirrors/linux --ignore-working-copy log -r.. -l100 --config-toml='revsets.short-prefixes=""'
Time (mean ± σ): 271.3 ms ± 9.9 ms [User: 183.8 ms, System: 87.7 ms]
Range (min … max): 250.5 ms … 282.7 ms 20 runs
Relative speed comparison
1.99 ± 0.16 target/release-with-debug/jj-0 -R ~/mirrors/linux --ignore-working-copy log -r.. -l100 --config-toml='revsets.short-prefixes=""'
1.53 ± 0.12 target/release-with-debug/jj-1 -R ~/mirrors/linux --ignore-working-copy log -r.. -l100 --config-toml='revsets.short-prefixes=""'
```
"jj status" with working copy snapshot (watchman enabled):
```
% hyperfine --sort command --warmup 3 --runs 20 -L bin jj-0,jj-1,jj-2 \
-s "target/release-with-debug/{bin} -R ~/mirrors/linux debug reindex" \
"target/release-with-debug/{bin} -R ~/mirrors/linux \
status --config-toml='revsets.short-prefixes=\"\"'"
Benchmark 1: target/release-with-debug/jj-0 -R ~/mirrors/linux status --config-toml='revsets.short-prefixes=""'
Time (mean ± σ): 396.6 ms ± 10.1 ms [User: 300.7 ms, System: 94.0 ms]
Range (min … max): 373.6 ms … 408.0 ms 20 runs
Benchmark 2: target/release-with-debug/jj-1 -R ~/mirrors/linux status --config-toml='revsets.short-prefixes=""'
Time (mean ± σ): 318.6 ms ± 12.6 ms [User: 219.1 ms, System: 94.1 ms]
Range (min … max): 294.2 ms … 333.0 ms 20 runs
Relative speed comparison
1.85 ± 0.14 target/release-with-debug/jj-0 -R ~/mirrors/linux status --config-toml='revsets.short-prefixes=""'
1.48 ± 0.12 target/release-with-debug/jj-1 -R ~/mirrors/linux status --config-toml='revsets.short-prefixes=""'
```
These methods are basically the same as the commit_id versions, but
resolve_change_id_prefix() is a bit more involved as we need to gather matches
from multiple segments.
In resolve_change_id_prefix(), I've implemented two different ways of
collecting the overflow items. I don't think they impact the performance,
but we can switch to the alternative method as needed.
This basically means that the change ids are interned. We'll implement binary
search over the sorted change ids table. The table could be sorted differently
for better cache locality, but it is in lexicographical order for simplicity.
With my testing, the cost of the id lookup isn't dominant.
Unlike the parent entries, the size of the per-id overflow items isn't saved.
That's s because the number of the same-change-id commits is either 1 or many.
It doesn't make sense to allocate 8 bytes for each change id. Instead, we'll
pay extra indirection cost to determine the size.
I'm going to add change id overflow table whose elements are of LocalPosition
type. Let's make sure that the serialization code would break if we changed
the underlying data type.
Apparently, gix has 100ms timeout. Since this test tries to create contended
situation, it's possible that the ref lock can't be acquired. I've added
upper bound to the retry loop at b37293fa68 "tests: add upper bound to
test_concurrent_read_write_commit() loop", so ignoring arbitrary errors
should be okay.
The problem can be reproduced on my Linux machine by inserting 10ms sleep() to
gix and increasing the concurrency.
Fixes#3069
This is for completeness and to avoid accidents such as someone calling
`ContentHash::hash(1234u32.to_le_bytes())` and expecting it to hash properly as
a u32 instead of a 4 byte slice, which produces a different hash due to hashing
the length of the slice before its contents.
