feat: TOML based config for rust-analyzer
> Important
>
> We don't promise _**any**_ stability with this feature yet, any configs exposed may be removed again, the grouping may change etc.
# TOML Based Config for RA
This PR ( addresses #13529 and this is a follow-up PR on #16639 ) makes rust-analyzer configurable by configuration files called `rust-analyzer.toml`. Files **must** be named `rust-analyzer.toml`. There is not a strict rule regarding where the files should be placed, but it is recommended to put them near a file that triggers server to start (i.e., `Cargo.{toml,lock}`, `rust-project.json`).
## Configuration Types
Previous configuration keys are now split into three different classes.
1. Client keys: These keys only make sense when set by the client (e.g., by setting them in `settings.json` in VSCode). They are but a small portion of this list. One such example is `rust_analyzer.files_watcher`, based on which either the client or the server will be responsible for watching for changes made to project files.
2. Global keys: These keys apply to the entire workspace and can only be set on the very top layers of the hierarchy. The next section gives instructions on which layers these are.
3. Local keys: Keys that can be changed for each crate if desired.
### How Am I Supposed To Know If A Config Is Gl/Loc/Cl ?
#17101
## Configuration Hierarchy
There are 5 levels in the configuration hierarchy. When a key is searched for, it is searched in a bottom-up depth-first fashion.
### Default Configuration
**Scope**: Global, Local, and Client
This is a hard-coded set of configurations. When a configuration key could not be found, then its default value applies.
### User configuration
**Scope**: Global, Local
If you want your configurations to apply to **every** project you have, you can do so by setting them in your `$CONFIG_DIR/rust-analyzer/rust-analyzer.toml` file, where `$CONFIG_DIR` is :
| Platform | Value | Example |
| ------- | ------------------------------------- | ---------------------------------------- |
| Linux | `$XDG_CONFIG_HOME` or `$HOME`/.config | /home/alice/.config |
| macOS | `$HOME`/Library/Application Support | /Users/Alice/Library/Application Support |
| Windows | `{FOLDERID_RoamingAppData}` | C:\Users\Alice\AppData\Roaming |
### Client configuration
**Scope**: Global, Local, and Client
Previously, the only way to configure rust-analyzer was to configure it from the settings of the Client you are using. This level corresponds to that.
> With this PR, you don't need to port anything to benefit from new features. You can continue to use your old settings as they are.
### Workspace Root Configuration
**Scope**: Global, Local
Rust-analyzer already used the path of the workspace you opened in your Client. We used this information to create a configuration file that won't affect your other projects and define global level configurations at the same time.
### Local Configuration
**Scope**: Local
You can also configure rust-analyzer on a crate level. Although it is not an error to define global ( or client ) level keys in such files, they won't be taken into consideration by the server. Defined local keys will affect the crate in which they are defined and crate's descendants. Internally, a Rust project is split into what we call `SourceRoot`s. This, although with exceptions, is equal to splitting a project into crates.
> You may choose to have more than one `rust-analyzer.toml` files within a `SourceRoot`, but among them, the one closer to the project root will be
fix: do not resolve prelude within block modules
fix#17338 (continuing from #17251).
In #17251, we injected preludes into non-top-level modules, which leading to r-a to directly resolve names in preludes in block modules. This PR fix it by checking whether the module is a pseudo-module introduced by blocks. (similar to what we do for extern preludes)
Feat: hide double underscored symbols from symbol search
Fixes#17272 by changing the default behavior of query to skip results that start with `__` (two underscores).
Not sure if this has any far reaching implications - a review would help to understand if this is the right place to do the filtering, and if it's fine to do it by default on the query.
If you type `__` as your search, then we'll show the matching double unders, just in case you actually need the symbol.
Fix: infer type of async block with tail return expr
Fixes#17106
The `infer_async_block` method calls the `infer_block` method internally, which returns the never type without coercion when `tail_expr` is `None` and `ctx.diverges` is `Diverges::Always`.This is the reason for the bug in this issue.
cfce2bb46d/crates/hir-ty/src/infer/expr.rs (L1411-L1413)
This PR solves the bug by adding a process to coerce after calling `infer_block` method.
This code passes all the tests, including tests I added for this isuue, however, I am not sure if this solution is right. I think that this solution is an ad hoc solution. So, I would appreciate to have your review.
I apologize if I'm off the mark, but `infer_async_block` method should be rewritten to share code with the process of infering type of `expr::Closure` instead of the `infer_block` method. That way it will be closer to the infer process of rustc.
When viewing traces, it's slightly confusing when the span name doesn't
match the function name. Ensure the names are consistent.
(It might be worth moving most of these to use #[tracing::instrument]
so the name can never go stale. @davidbarsky suggested that is marginally
slower, so I've just done the simple change here.)
Support hovering limits for adts
Fix#17009
1. Currently, r-a supports limiting the number of struct fields displayed when hovering. This PR extends it to support enum variants and union fields. Since the display of these three (ADTs) is similar, this PR extends 'hover_show_structFields' to 'hover_show_adtFieldsOrVariants'.
2. This PR also resolved the problem that the layout of ADT was not restricted by display limitations when hovering on the Self type.
3. Additionally, this PR changes the default value of display limitations to `10` (instead of the original `null`), which helps users discover this feature.
It is bitset semantically --- many categorical things can be true about
a reference at the same time.
In parciular, a reference can be a "test" and a "write" at the same
time.
