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.
Currently, we only provide functions to read references directly from a
repository's reference store via e.g. `git_reference_lookup`. But in
some cases, we may want to read files not connected to the current
repository, e.g. when looking up HEAD of connected work trees. This
commit implements `git_reference__read_head`, which will read out and
allocate a reference at an arbitrary path.
Error messages should be sentence fragments, and therefore:
1. Should not begin with a capital letter,
2. Should not conclude with punctuation, and
3. Should not end a sentence and begin a new one
Introduce GIT_OPT_ENABLE_SYMBOLIC_REF_TARGET_VALIDATION option.
Setting this option to 0 allows
validation of a symbolic ref's target to be bypassed.
This option is enabled by default.
This mechanism is added primarily to address a discrepancy between git
behaviour and libgit2 behaviour, whereby the former allows the symbolic
ref target to carry an arbitrary string and the latter does not, so:
$ git symbolic-ref refs/heads/foo bar
$ cat .git/refs/heads/foo
ref: bar
where as attempting the same via libgit2 raises an error:
The given reference name 'bar' is not valid
this mechanism also allows those that might want to make use of
git's more lenient treatment of symbolic ref targets to do so.
If we cannot dwim the input, set the error message to be explicit about
that. Otherwise we leave the error for the last failed lookup, which
can be rather unexpected as it mentions a remote when the user thought
they were trying to look up a branch.
We want to use the "checkout: moving from ..." message in order to let
git know when a change of branch has happened. Make the convenience
functions for this goal write this message.
The signature for the reflog is not something which changes
dynamically. Almost all uses will be NULL, since we want for the
repository's default identity to be used, making it noise.
In order to allow for changing the identity, we instead provide
git_repository_set_ident() and git_repository_ident() which allow a user
to override the choice of signature.
Make our overflow checking look more like gcc and clang's, so that
we can substitute it out with the compiler instrinsics on platforms
that support it. This means dropping the ability to pass `NULL` as
an out parameter.
As a result, the macros also get updated to reflect this as well.
A transaction allows you to lock multiple references and set up changes
for them before applying the changes all at once (or as close as the
backend supports).
This can be used for replication purposes, or for making sure some
operations run when the reference is locked and thus cannot be changed.
This fixes two issues I found when core.precomposeunicode is enabled:
* When creating a reference with a NFD string, the returned
git_reference would return this NFD string as the reference’s
name. But when looking up the reference later, the name would
then be returned as NFC string.
* Renaming a reference would not honor the core.precomposeunicode and
apply no normalization to the new reference name.
Change the name to _matching() intead of _if(), and force _set_target()
to be a conditional update. If the user doesn't care about the old
value, they should use git_reference_create().
Any well-behaved program should write a descriptive message to the
reflog whenever it updates a reference. Let's make this more prominent
by removing the version without the reflog parameters.
This changes the behavior of callbacks so that the callback error
code is not converted into GIT_EUSER and instead we propagate the
return value through to the caller. Instead of using the
giterr_capture and giterr_restore functions, we now rely on all
functions to pass back the return value from a callback.
To avoid having a return value with no error message, the user
can call the public giterr_set_str or some such function to set
an error message. There is a new helper 'giterr_set_callback'
that functions can invoke after making a callback which ensures
that some error message was set in case the callback did not set
one.
In places where the sign of the callback return value is
meaningful (e.g. positive to skip, negative to abort), only the
negative values are returned back to the caller, obviously, since
the other values allow for continuing the loop.
The hardest parts of this were in the checkout code where positive
return values were overloaded as meaningful values for checkout.
I fixed this by adding an output parameter to many of the internal
checkout functions and removing the overload. This added some
code, but it is probably a better implementation.
There is some funkiness in the network code where user provided
callbacks could be returning a positive or a negative value and
we want to rely on that to cancel the loop. There are still a
couple places where an user error might get turned into GIT_EUSER
there, I think, though none exercised by the tests.
