Summary:
Similar to D7121487 (af8ecd5f80) but works for mutation store. This makes sure at the Rust
layer, mutation entries won't get lost after rebasing or metaeditting a set of
commits where a subset of the commits being edited has mutation relations.
Unlike the Python layer, the Rust layer works for mutation chains. Therefore
some of the tests changes.
Reviewed By: markbt
Differential Revision: D22174991
fbshipit-source-id: d62f7c1071fc71f939ec8771ac5968b992aa253c
Summary:
Enforcing 1:1 handling is causing trouble for multiple reasons:
- Test cases like "Metaedit with descendant folded commits" in
test-mutation.t requires handling non-1:1 entries.
- Currently operations like `metaedit-copy` uses two predecessors (edited,
copied). It is considered 1:1 rewrite (rewriting 1 commit to
another 1 commit). However, it does not use multiple records, therefore
cannot be distinguished from `fold`, which is not 1:1 rewrite and also
has multiple predecessors. We want to include the `metaedit-copy`
entries in the 1:1 DAG too.
Therefore lift the 1:1 restriction and let's see how it works.
Reviewed By: markbt
Differential Revision: D22175008
fbshipit-source-id: 84d870dbcc433a0d0e5611a83c93781bfa59d035
Summary: This allows other kinds of DAG to implement the operations.
Reviewed By: sfilipco
Differential Revision: D21626220
fbshipit-source-id: 896c5ccebb1672324d346dfca6bcac9b4d3b4929
Summary:
This decouples DagAlgorithm from the IdMap + IdDag backend, making it possible
to support other kinds of backends of DagAlgorithm (ex. a revlog backend).
Reviewed By: sfilipco
Differential Revision: D21626200
fbshipit-source-id: f53cc271a200062e9c02f739b6453e1d7de84e6d
Summary:
Part of the mutation graph (excluding split and fold) can fit in the DAG
abstraction. Add a method to do that. This allows cross-dag calculations
like:
changelogdag = ... # suppose available by segmented changelog
# mutdag and changelogdag are independent (might have different nodes),
# with full DAG operations on either of them.
mutdag = mutation.getdag(...)
mutdag.heads(mutdag.descendants([node])) & changelogdag.descendants([node2]) # now possible
Comparing to the current situation, this has some advantages:
- No need to couple the "visibility", "filtered node" logic to the mutation
layer. The unknown nodes can be filtered out naturally by a set "&"
operation.
- DAG operations like heads, roots can be performed on mutdag when it's
previously impossible. We also get operations like visualization for free.
There are some limitations, though:
- The DAG cannot represent non 1:1 modifications (fold, split) losslessly.
Those relationships are simply ignored for now.
- The MemNameDag is not lazy. Reading a long chain of amends might be slow.
For most normal use-cases it is probably okay. If it becomes an issue we
can seek for other solutions, for example, store part of mutationstore
directly in a DAG format on disk, or have fast paths to bypass long
predecessor chain calculation.
Reviewed By: DurhamG
Differential Revision: D21486521
fbshipit-source-id: 03624c8e9803eb1852b3034b8f245555ec582e85
Summary: Move the MutationEntry type to the Mercurial types crate. This will allow us to use it from Mononoke.
Reviewed By: quark-zju
Differential Revision: D20871338
fbshipit-source-id: 8de3bb8a2673673bc4c8a6cc7578a0a76358c14a
Summary:
The mutation store stores entries with a floating-point timestamp. This
pattern was copied from obsmarkers.
However, Mercurial uses integer timestamps in the commit metadata (the
parser supports floats for historical reasons, but only stores integer
timestamps). Mononoke also uses integer timestamps in its `DateTime`
type.
To keep things simple, switch to using integer timestamps for mutation
entries. Existing entries with floating point timestamps are truncated.
Add a new entry format version that encodes the timestamp as an integer.
For now, continue to generate the old version so that old clients can
read entries created by new clients.
Reviewed By: quark-zju
Differential Revision: D20444366
fbshipit-source-id: 4d6d9851aacb314abea19b87c9d0130c47fdf512
Summary:
Tracking the origin of mutation entries did not prove useful, and just creates
an un-necessary overhead. Remove the tracking and repurpose the field as a
version field.
Reviewed By: quark-zju
Differential Revision: D20444365
fbshipit-source-id: 65ff11ee8cfe77d5e67a83d03a510541d58ef69b
Summary:
I thought the index function could be the bottleneck. However, the Log reading
(xxhash, decoding vlqs) can be much slower for very long entries. Therefore
using bytes as the lag threshold is better. It does leaked the Log
implementation details (how it encodes an entry) to some extend, though.
Reverts D20042045 and D20043116 logically. The lagging calculation is using
the new Index::get_original_meta API, which is easier to verify correctness
(In fact, it seems the old code is wrong - it might skip Index flushes if
sync() is called multiple times without flushing).
This should mitigate an issue where a huge entry (generated by `hg trace`) in
blackbox does not get indexed in time and cause performance regressions.
Reviewed By: DurhamG
Differential Revision: D20286508
fbshipit-source-id: 7cd694b58b95537490047fb1834c16b30d102f18
Summary:
D20042045 changes the meaning of "lag_threshold". Update the value in mutation
store accordingly.
Reviewed By: DurhamG
Differential Revision: D20043116
fbshipit-source-id: 154e6dc2aa88ab0a9a9b21929ae5fa6163dcd403
Summary: Username as utf8, so let's make mutationmarker treat them as such.
Reviewed By: xavierd
Differential Revision: D19649887
fbshipit-source-id: 3f8b2db434a57ee8ee3017de8d925c19a2002b20
Summary:
This diff replaces eden's dependencies on failure::Error with anyhow::Error.
Failure's error type requires all errors to have an implementation of failure's own failure::Fail trait in order for cause chains and backtraces to work. The necessary methods for this functionality have made their way into the standard library error trait, so modern error libraries build directly on std::error::Error rather than something like failure::Fail. Once we are no longer tied to failure 0.1's Fail trait, different parts of the codebase will be free to use any std::error::Error-based libraries they like while still working nicely together.
Reviewed By: xavierd
Differential Revision: D18576093
fbshipit-source-id: e2d862b659450f2969520d9b74877913fabb2e5d
Summary:
This diff replaces code of the form:
```
use failure::Fail;
#[derive(Fail, Debug)]
pub enum ErrorKind {
#[fail(display = "something failed {} times", _0)]
Failed(usize),
}
```
with:
```
use thiserror::Error;
#[derive(Error, Debug)]
pub enum ErrorKind {
#[error("something failed {0} times")]
Failed(usize),
}
```
The former emits an implementation of failure 0.1's `Fail` trait while the latter emits an impl of `std::error::Error`. Failure provides a blanket impl of `Fail` for any type that implements `Error`, so these `Error` impls are strictly more general. Each of these error types will continue to have exactly the same `Fail` impl that it did before this change, but now also has the appropriate `std::error::Error` impl which sets us up for dropping our various dependencies on `Fail` throughout the codebase.
Reviewed By: Imxset21
Differential Revision: D18523700
fbshipit-source-id: 0e43b10d5dfa79820663212391ecbf4aeaac2d41
Summary:
This diff is preparation for migrating off of failure::Fail / failure::Error for errors in favor of errors that implement std::error::Error. The Fallible terminology is unique to failure and in non-failure code we should be using Result<T>. To minimize the size of the eventual diff that removes failure, this codemod replaces all use of Fallible with Result by:
- In modules that do not use Result<T, E>, we import `failure::Fallible as Result`;
- In modules that use a mix of Result<T, E> and Fallible<T> (only 5) we define `type Result<T, E = failure::Error> = std::result::Result<T, E>` to allow both Result<T> and Result<T, E> to work simultaneously.
Reviewed By: Imxset21
Differential Revision: D18499758
fbshipit-source-id: 9f5a54c47f81fdeedbc6003cef42a1194eee55bf
Summary:
In preparation for merging fb-mercurial sources to the Eden repository,
move everything from the top-level directory into an `eden/scm`
subdirectory.
