The current signature of `git_worktree_prune` accepts a flags field to
alter its behavior. This is not as flexible as we'd like it to be when
we want to enable passing additional options in the future. As the
function has not been part of any release yet, we are still free to
alter its current signature. This commit does so by using our usual
pattern of an options structure, which is easily extendable without
breaking the API.
When creating a new worktree, we do have a potential race with us
creating the worktree and another process trying to delete the same
worktree as it is being created. As such, the upstream git project has
introduced a flag `git worktree add --locked`, which will cause the
newly created worktree to be locked immediately after its creation. This
mitigates the race condition.
We want to be able to mirror the same behavior. As such, a new flag
`locked` is added to the options structure of `git_worktree_add` which
allows the user to enable this behavior.
The `git_worktree_add` function currently accepts only a path and name
for the new work tree. As we may want to expand these parameters in
future versions without adding additional parameters to the function for
every option, this commit introduces our typical pattern of an options
struct. Right now, this structure is still empty, which will change with
the next commit.
Whenever we rename a branch, we update the repository's symbolic HEAD
reference if it currently points to the branch that is to be renamed.
But with the introduction of worktrees, we also have to iterate over all
HEADs of linked worktrees to adjust them. Do so.
It is possible to specify submodule URLs relative to the repository
location. E.g. having a submodule with URL "../submodule" will look for
the submodule at "repo/../submodule".
With the introduction of worktrees, though, we cannot simply resolve the
URL relative to the repository location itself. If the repository for
which a URL is to be resolved is a working tree, we have to resolve the
URL relative to the parent's repository path. Otherwise, the URL would
change depending on where the working tree is located.
Fix this by special-casing when we have a working tree while getting the
URL base.
References for a repository are usually created inside of its gitdir.
When using worktrees, though, these references are not to be created
inside the worktree gitdir, but instead inside the gitdir of its parent
repository, which is the commondir. Like this, branches will still be
available after the worktree itself has been deleted.
The filesystem refdb currently still creates new references inside of
the gitdir. Fix this and have it create references in commondir.
The three link files "worktree/.git", ".git/worktrees/<name>/commondir"
and ".git/worktrees/<name>/gitdir" should always contain absolute and
resolved paths. Adjust the logic creating new worktrees to first use
`git_path_prettify_dir` before writing out these files, so that paths
are resolved first.
The working tree's parent path should not point to the parent's gitdir,
but to the parent's working directory. Pointing to the gitdir would not
make any sense, as the parent's working directory is actually equal to
both repository's common directory.
Fix the issue.
While we already provide functionality to look up a worktree from a
repository, we cannot do so the other way round. That is given a
repository, we want to look up its worktree if it actually exists.
Getting the worktree of a repository is useful when we want to get
certain meta information like the parent's location, getting the locked
status, etc.
When opening a worktree via the gitdir of its parent repository
we fail to correctly set up the worktree's working directory. The
problem here is two-fold: we first fail to see that the gitdir
actually is a gitdir of a working tree and then subsequently
fail to determine the working tree location from the gitdir.
The first problem of not noticing a gitdir belongs to a worktree
can be solved by checking for the existence of a `gitdir` file in
the gitdir. This file points back to the gitlink file located in
the working tree's working directory. As this file only exists
for worktrees, it should be sufficient indication of the gitdir
belonging to a worktree.
The second problem, that is determining the location of the
worktree's working directory, can then be solved by reading the
`gitdir` file in the working directory's gitdir. When we now
resolve relative paths and strip the final `.git` component, we
have the actual worktree's working directory location.
The `path_repository` variable is actually confusing to think
about, as it is not always clear what the repository actually is.
It may either be the path to the folder containing worktree and
.git directory, the path to .git itself, a worktree or something
entirely different. Actually, the intent of the variable is to
hold the path to the gitdir, which is either the .git directory
or the bare repository.
Rename the variable to `gitdir` to avoid confusion. While at it,
also rename `path_gitlink` to `gitlink` to improve consistency.
If a branch is already checked out in a working tree we are not
allowed to check out that branch in another repository. Introduce
this restriction when setting a repository's HEAD.
Implement `git_repository_head_for_worktree` and
`git_repository_head_detached_for_worktree` for directly accessing a
worktree's HEAD without opening it as a `git_repository` first.
Implement the `git_worktree_prune` function. This function can be
used to delete working trees from a repository. According to the
flags passed to it, it can either delete the working tree's
gitdir only or both gitdir and the working directory.
Working trees support locking by creating a file `locked` inside
the tree's gitdir with an optional reason inside. Support this
feature by adding functions to get and set the locking status.
Add a new function that checks wether a given `struct
git_worktree` is valid. The validation includes checking if the
gitdir, parent directory and common directory are present.
Introduce a new `struct git_worktree`, which holds information
about a possible working tree connected to a repository.
Introduce functions to allow opening working trees for a
repository.
A repository's configuartion file can always be found in the
GIT_COMMON_DIR, which has been newly introduced. For normal
repositories this does change nothing, but for working trees this
change allows to access the shared configuration file.
The refdb_fs_backend is not aware of the git commondir, which
stores common objects like the o bject database and packed/loose
refereensces when worktrees are used.
Make refdb_fs_backend aware of the common directory by
introducing a new commonpath variable that points to the actual
common path of the database and using it instead of the gitdir
for the mentioned objects.
The commondir variable stores the path to the common directory.
The common directory is used to store objects and references
shared across multiple repositories. A current use case is the
newly introduced `git worktree` feature, which sets up a separate
working copy, where the backing git object store and references
are pointed to by the common directory.
