This crate provides the [Repository
] abstraction which serves as a hub into all the functionality of git.
It's powerful and won't sacrifice performance while still increasing convenience compared to using the sub-crates individually. Sometimes it may hide complexity under the assumption that the performance difference doesn't matter for all but the fewest tools out there, which would be using the underlying crates directly or file an issue.
The prelude and extensions
With use git_repository::prelude::*
you should be ready to go as it pulls in various extension traits to make functionality
available on objects that may use it.
The method signatures are still complex and may require various arguments for configuration and cache control.
Easy-Mode
Most extensions to existing objects provide an obj_with_extension.easy(&repo).an_easier_version_of_a_method()
or easy(&repo)
method to hide all complex arguments and sacrifice some performance for a lot of convenience.
When starting out, use easy(…)
and migrate to the more detailed method signatures to squeeze out more performance.
Shortcomings & Limitations
- Only one
easy::Object
or derivatives can be held in memory at a time, perEasy*
. - Changes made to the configuration, packs, and alternates aren't picked up automatically if they aren't
made through the underlying
Repository
instance. Run one of the [refresh*()
][prelude::RepositoryAccessExt] to trigger an update. Also note that this is only a consideration for long-running processes.
Design Sketch
Goal is to make the lower-level plumbing available without having to deal with any caches or buffers, and avoid any allocation beyond sizing the buffer to fit the biggest object seen so far.
- no implicit object lookups, thus
Oid
needs to get anObject
first to start out with data viaobject()
- Objects with
Ref
suffix can only exist one at a time unless they are transformed into an owned version of it OR multipleEasy
handles are present, each providing another 'slot' for an object as long as its retrieved through the respectiveEasy
object. ObjectRef
blocks the current buffer, hence many of its operations that use the buffer are consuming- All methods that access a any field from
Easy
's mutableState
are fallible, and returneasy::Result<_>
at least, to avoid panics if the field can't be referenced due to borrow rules ofRefCell
. - Anything attached to
Access
can be detached to lift the object limit or make themSend
-able. They can beattached
to anotherAccess
if needed. git-repository
functions related toAccess
extensions will always return attached versions of return values, likeOid
instead ofgit_hash::ObjectId
,ObjectRef
instead ofgit_odb::data::Object
, orReference
instead ofgit_ref::Reference
.- Obtaining mutable is currently a weak spot as these only work with Arc right now and can't work with
Rc<RefCell>
due to missing GATs, presumably. AllEasy*!Exclusive
types are unable to provide a mutable reference to the underlying repository. However, other ways to adjust theRepository
of long-running applications are possible. For instance, there could be a flag that indicates a newRepository
should be created (for instance, after it was changed) which causes the next server connection to create a new one. This instance is the one to use when spawning newEasyArc
instances.
Terminology
WorkingTree and WorkTree
When reading the documentation of the canonical git-worktree program one gets the impression work tree and working tree are used interchangeably. We use the term work tree only and try to do so consistently as its shorter and assumed to be the same.
Cargo-features
With the optional "unstable" cargo feature
To make using sub-crates easier these are re-exported into the root of this crate. Note that these may change their major version even if this crate doesn't, hence breaking downstream.
git_repository::
- [
hash
] - [
url
] - [
actor
] - [
bstr
][bstr] - [
objs
] - [
odb
] - [
pack
][odb::pack] - [
refs
] - [
interrupt
] - [
tempfile
] - [
lock
] - [
traverse
] - [
diff
] - [
parallel
] - [
Progress
] - [
progress
] - [
interrupt
] - [
protocol
] - [
transport
][protocol::transport]