When dealing with proc macros, there are two very different kinds of
errors:
* first, usual errors of "proc macro panicked on this particular input"
* second, the proc macro server might day if the user, eg, kills it
First kind of errors are expected and are a normal output, while the
second kind are genuine IO-errors.
For this reason, we use a curious nested result here: `Result<Result<T,
E1>, E2>` pattern, which is 100% inspired by http://sled.rs/errors.html
I don't think there's anything wrong with project_model depending on
proc_macro_api directly -- fundamentally, both are about gluing our pure
data model to the messy outside world.
However, it's easy enough to avoid the dependency, so why not.
As an additional consideration, `proc_macro_api` now pulls in `base_db`.
project_model should definitely not depend on that!
The current logic used to transfer global_excludes into vfs exclusions
only transfers global_excludes that are the parent of an item in
dirs.include.
This commit additionally adds an item from global_exclude to the vfs
exclusions if the global_exclude is a child of an included item.
Conceptually, using a *message* here is wrong, because this is a
"status", rather than "point in time" thing. But statuses are an LSP
extension, while messages are stable. As a compromise, send message only
for more critical `metadata` failures, and only once per state change.
In some situations we reloaded the workspace in the tests after having reported
to be ready. There's two fixes here:
1. Add a version to the VFS config and include that version in progress reports,
so that we don't think we're done prematurely;
2. Delay status transitions until after changes are applied. Otherwise the last
change during loading can potentially trigger a workspace reload, if it contains
interesting changes.
I've noticed a bunch of "main loop too long" warnings in console when
typing in Cargo.toml. Profiling showed that the culprit is `rustc
--print cfg` call.
I moved it to the background project loading phase, where it belongs.
This highlighted a problem: we generally use single `cfg`, while it
really should be per crate.
After we started reporting progress when running cargo check during
loading, it is possible to crash the client with two identical progress
tokens.
This points to a deeper issue: we might be running several cargo checks
concurrently, which doesn't make sense.
This commit linearizes all workspace fetches, making sure no updates are
lost.
As an additional touch, it also normalizes progress & result reporting,
to make sure they stand in sync.
Rather than eagerly converting JSON, we losslessly keep it as is, and
change the shape of user-submitted data at the last moment.
This also allows us to remove a bunch of wrong Defaults
