The `ChangeIdIndex` type is currently in defined in the `revset`
module because that's the only placed it's used. However, I'd like to
start using it directly from `index`. The idea is to make it possible
to create a `ChangeIdIndex` given a set of heads, without first
creating a `Revset`.
I'll probably add change id lookup methods to CompositeIndex. The Index trait
won't gain resolve_change_id_prefix(), but I also renamed its resolve_prefix()
for consistency.
It seems generally useful to optimize revset expressions in
`evaluate_programmatic()` so the caller doesn't have to remember to do
it. It should generally be cheap to do so even if it's often not
needed.
`RevsetExpression::resolve()` is meant for programmatically created
expressions. In particular, it may not contain symbols. Let's try to
clarify that by renaming the function and documenting it.
As discussed in Discord, it's less useful if remote_branches() included
Git-tracking branches. Users wouldn't consider the backing Git repo as
a remote.
We could allow explicit 'remote_branches(remote=exact:"git")' query by changing
the default remote pattern to something like 'remote=~exact:"git"'. I don't
know which will be better overall, but we don't have support for negative
patterns anyway.
This isn't important, but I'm going to change remote_targets to store RemoteRef
instead of RefTarget, so I went ahead and change the other field types as well.
There's a subtle behavior change. Unlike the original remove_remote_branch(),
remote_views entry is not discarded when the branches map becomes empty. The
reasoning here is that the remote view can be added/removed when the remote
is added/removed respectively, though that's not implemented yet. Since the
serialized data cannot represent an empty remote, such view may generate
non-unique content hash.
These functions depend heavily on the underlying data structure, and I haven't
decided abstract View API to access to per-remote data types. Let's use the
underlying data type for now.
Since both has_id() and resolve_prefix() do binary search, their costs are
practically the same. I think has_id() would complete with fewer ops, but such
level of optimization wouldn't be needed here. More importantly, this ensures
that unreachable commits aren't imported by GitBackend::read_commit().
This adds a new `revset-aliases.immutable_heads()s` config for
defining the set of immutable commits. The set is defined as the
configured revset, as well as its ancestors, and the root commit
commit (even if the configured set is empty).
This patch also adds enforcement of the config where we already had
checks preventing rewrite of the root commit. The working-copy commit
is implicitly assumed to be writable in most cases. Specifically, we
won't prevent amending the working copy even if the user includes it
in the config but we do prevent `jj edit @` in that case. That seems
good enough to me. Maybe we should emit a warning when the working
copy is in the set of immutable commits.
Maybe we should add support for something more like [Mercurial's
phases](https://wiki.mercurial-scm.org/Phases), which is propagated on
push and pull. There's already some affordance for that in the view
object's `public_heads` field. However, this is simpler, especially
since we can't propagate the phase to Git remotes, and seems like a
good start. Also, it lets you say that commits authored by other users
are immutable, for example.
For now, the functionality is in the CLI library. I'm not sure if we
want to move it into the library crate. I'm leaning towards letting
library users do whatever they want without being restricted by
immutable commits. I do think we should move the functionality into a
future `ui-lib` or `ui-util` crate. That crate would have most of the
functionality in the current `cli_util` module (but in a
non-CLI-specific form).
I originally attempted to embed function parameters in RevsetAliasId. That's
probably why these getters return id. Let's move id construction to callers
since the id only serves as a recursion blocker.
Since we have overloaded operator symbols, we need to deduplicate them
upfront. Legacy and compat operators are also removed from the suggestion.
It's a bit ugly to mutate the error struct before calling Error::renamed_rule(),
but I think it's still better than reimplementing message formatting function.
Since e7e49527efdf "git: ensure that remote branches never diverge", the last
known "refs/remotes" ref should be synced with the corresponding remote branch.
So we can always trust the branch@remote expression. We don't need "refs/tags"
lookup either since tags should have been imported by git::import_refs().
FWIW, I'm thinking of reorganizing view.git_refs() map as per-remote views.
It would be nice if we can get rid of revsets and template keywords exposing
low-level Git ref primitives.
Suppose "x::y" is the operator that defaults to "root()::visible_heads()"
respectively, "::" is identical to "all()". Since we've just changed the
behavior of "..y", ".." is now "root()..visible_heads()" meaning "~root()".
This is what I proposed in #2095. @ is now an operator to concatenate symbols.
Unlike the other operators, lhs/rhs of @ is not a target of alias substitution.
'x' in 'x@y' doesn't look like a named variable, though it's technically
possible to allow definition of an alias expanded to a symbol of specific remote
or vice versa. This will probably apply to the kind:pattern syntax, where
aliases are expanded due to the current implementation restriction. I've added
a TODO comment about that.
`revset::parse()` already has a `RevsetWorkspaceContext` argument, so
I think it makes sense to put that and the other context arguments
into a larger `RevsetParseContext` object.
We resolve file paths into repo-relative paths while parsing the
revset expression, so I think it's consistent to also resolve which
workspace "@" refers to while parsing it. That means we won't need the
workspace context both while parsing and while resolving symbols.
In order to break things like `author("martinvonz@")` (thanks to @yuja
for catching this), I also changed the parsing of working-copy
expressions so they are not allowed to be
quoted. `author(martinvonz@)` will therefore be an error now. That
seems like a small improvement anyway, since we have recently talked
about making `root` and `[workspace]@` not parsed as other symbols.
Per discussion in #2107, I believe "exact" is preferred.
We can also change the default to exact match, but it doesn't always make
sense. Exact match would be useful for branches(), but not for description().
We could define default per predicate function, but I'm pretty sure I cannot
remember which one is which.
git-branchless calls it a substring, so let's do the same.
FWIW, I copied literal:_ from Mercurial, but it's exact:_ in git-branchless.
I have no idea which one is preferred. Since this feature isn't released, we
can freely change it if exact:_ makes more sense.
https://github.com/arxanas/git-branchless/wiki/Reference:-Revsets#patterns
The syntax is slightly different from Mercurial. In Mercurial, a pattern must
be quoted like "<kind>:<needle>". In JJ, <kind> is a separate parsing node, and
it must not appear in a quoted string. This allows us to report unknown prefix
as an error.
There's another subtle behavior difference. In Mercurial, branch(unknown) is
an error, whereas our branches(literal:unknown) is resolved to an empty set.
I think erroring out doesn't make sense for JJ since branches() by default
performs substring matching, so its behavior is more like a filter.
The parser abuses DAG range syntax for now. It can be rewritten once we remove
the deprecated x:y range syntax.