This will really become necessary when we implement generics, but even now, it
allows us to reason 'backwards' to infer types of expressions that we didn't
understand for some reason.
We use ena, the union-find implementation extracted from rustc, to keep track of
type variables.
350: Super simple macro support r=matklad a=matklad
Super simple support for macros, mostly for figuring out how to fit them into the current architecture. Expansion is hard-coded and string based (mid-term, we should try to copy-paste macro-by-example expander from rustc).
Ideally, we should handle
* highlighting inside the macro (done)
* extend selection inside the macro
* completion inside the macro
* indexing structs, produced by the macro
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
341: Bump languageserver-types from 0.53.0 to 0.53.1 r=matklad a=dependabot[bot]
Bumps [languageserver-types](https://github.com/gluon-lang/languageserver-types) from 0.53.0 to 0.53.1.
<details>
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- [`c78120b`](c78120bf28) Add `Clone` impl for HoverContents and related
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343: Bump arrayvec from 0.4.9 to 0.4.10 r=matklad a=dependabot[bot]
Bumps [arrayvec](https://github.com/bluss/arrayvec) from 0.4.9 to 0.4.10.
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344: Bump itertools from 0.7.11 to 0.8.0 r=matklad a=dependabot[bot]
Bumps [itertools](https://github.com/bluss/rust-itertools) from 0.7.11 to 0.8.0.
<details>
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325: implement translate_offset_with_edit r=matklad a=vemoo
- Implement `translate_offset_with_edit` to resolve#105
- Add proptest impls for text, offsets and edits and use them in tests for `translate_offset_with_edit` and `LineIndex`
- Added benchmark for `translate_offset_with_edit`
Co-authored-by: Bernardo <berublan@gmail.com>
332: Struct types r=matklad a=flodiebold
Infer types for struct fields, and add basic field completions. There's also some code for enums, but I focused on getting structs working.
There's still ways to go before this becomes useful: There's no autoderef (or even reference types) and no inference for `self`, for example.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
We need to be able to get the receiver even if there is no field name yet, and
currently "a." wouldn't get parsed as a field name at all. This seems to help.
326: resolved#324: remove unnecessary braces in use statement. r=matklad a=gfreezy
Add inspection for unnecessary braces in use statement
Co-authored-by: gfreezy <gfreezy@gmail.com>
327: Beginnings of type inference r=flodiebold a=flodiebold
I was a bit bored, so I thought I'd try to start implementing the type system and see how far I come 😉 This is obviously still extremely WIP, only very basic stuff working, but I thought I'd post this now to get some feedback as to whether this approach makes sense at all.
There's no user-visible effect yet, but the type inference has tests similar to the ones for the parser. My next step will probably be to implement struct types, after which this could probably be used to complete fields.
I realize this may all get thrown away when/if the compiler query system gets usable, but I feel like there are lots of IDE features that could be implemented with somewhat working type inference in the meantime 😄
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
302: WIP: Support tracing lsp requests. r=DJMcNab a=DJMcNab
EDIT: We need to work out a better way to handle settings before this can be merged. Help wanted
TODO: Debug why decorations are sent even when highlightingOn is disabled
This makes the log volume so high its impossible to work with anyway.
(Continuation of #84 [#99 only disabled using it, not making sure we don't send it]).
These logs can be used in https://microsoft.github.io/language-server-protocol/inspector/
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
This improving this code is not a good use of people-time, and this
might be the most performant approach nonwithstanding
an api for this use case being added to walkdir
315: Split completion into manageable components r=matklad a=matklad
The main idea here is to do completion in two phases:
* first, we figure out surrounding context
* then, we run a series of completers on the given context.
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
306: Finish weird exprs r=DJMcNab a=DJMcNab
Fix#290.
Note that I'm not certain my use of `p.nth(1) == Ident` is entirely consistent with `libsyntax` - in the original, [`is_union_item`](9622f9dc47/src/libsyntax/parse/parser.rs (L4593-L4596)) uses `t.is_ident() && !t.is_reserved_ident()`, whereas we effectively only do `is_ident`. However, I cannot find the definition of `is_reserved_ident` (even searching the rust repository only gives uses, no definitions), so this will have to do unless someone else can find it :|.
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
This isn't working properly because we don't dynamically disable or enable it
TODO: work out why highlighting can be enabled mid session.
TODO: Improve settings handling
273: Add a test to ensure that we can parse each file r=matklad a=DJMcNab
Note that this has a non-spurious failure in ra_analysis/src/mock_analysis.
Probably fixes#195.
If my understanding is correct, fixes#214 and fixes#225.
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
This fixes a common problem when running under VS Code, the user
doesn't have permissions to create a `log` directory in the CWD.
The old behavior can be re-enabled by setting RA_INTERNAL_MODE=1
The cast expression expected any type via types::type_() function,
but the language spec does only allow TypeNoBounds (types without direct extra bounds
via `+`).
**Example:**
```rust
fn test() {
6i8 as i32 + 5;
}
```
This fails, because the types::type_() function which should parse the type after the
as keyword is greedy, and takes all plus sign after path types as extra.
My proposed fix is to replace the not implemented `type_no_plus()` just calls (`type_()`)
function, which is used at several places. The replacement is `type_with_bounds_cond(p: &mut Parser, allow_bounds: bool)`, which passes the condition to relevant sub-parsers.
This function is then called by `type_()` and the new public `type_no_bounds()`.
271: Implement format hook r=matklad a=DJMcNab
Tentatively: fixes#155.
However, this does add all changes in staged files, which might not be desirable. However, I think we can't solve that without explicit support in rustfmt for it, so it should be fine.
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
267: Fix the extend keybinding r=DJMcNab a=DJMcNab
Make the extend selection keybinding less annoying for users not used to Injelli-J (myself included). Also fixes a minor style issue and runs `npm update`.
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
265: Refactor symbol resolve API r=matklad a=matklad
Introduce ReferenceResolution to avoid nesting to many non-nominal
types.
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
256: Improve/add use_item documentation r=matklad a=DJMcNab
Adds some documentation to use_item explaining all code paths (use imports are hard, especially with the ongoing discussion of anchored v. uniform paths - see https://github.com/rust-lang/rust/issues/55618 for what appears to be the latest developments)
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
253: Fix diagnostic fixes showing up everywhere r=matklad a=flodiebold
The LSP code action request always returned the fixes for all diagnostics anywhere in the file, because of a shadowed variable.
There's no test yet; I wasn't sure where to add it. I tried adding one in `heavy_tests`, but that's a bit uncomfortable because the code action response contains the (random) file paths. I could make it work, but wanted to ask beforehand what you think.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
250: Improve the suggestion for test functions r=DJMcNab a=DJMcNab
I haven't fully updated the previous commented out test - I don't know why it was commented out so some clarification would be welcome.
Co-authored-by: Daniel McNab <36049421+djmcnab@users.noreply.github.com>
Co-authored-by: DJMcNab <36049421+djmcnab@users.noreply.github.com>
252: Improve 'introduce variable' r=matklad a=flodiebold
- make it possible to extract a prefix of an expression statement (e.g.
`<|>foo.bar()<|>.baz()`)
- don't turn the last expression in a block into a let statement
- also fix a few typos
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
- make it possible to extract a prefix of an expression statement (e.g.
<|>foo.bar()<|>.baz())
- don't turn the last expression in a block into a let statement
"volatile" means "changes every time". That is, all transitive
rev-deps of volatile queries will be executed every time. We actually
need "dependencies".
Note that VSCode asks for completion after *first* `:` as well:
use crate:
we use hacks to protect against that, and to give completions only
after the second `:`.
207: Finish implementing char validation r=aochagavia a=aochagavia
The only thing missing right now are good integration tests (and maybe more descriptive error messages)
Co-authored-by: Adolfo Ochagavía <github@adolfo.ochagavia.xyz>
167: Attempt to extract useful comments from function signatures r=matklad a=kjeremy
I'm trying to extract useful function comments for signature info. This will also be useful for hover. This is a WIP (and actually works pretty well!) but I don't think it's the right approach long term so some guidance would be appreciated so that we could also get comments for say types and variable instances etc.
Currently `test_fn_signature_with_simple_doc` fails due to a bug in `extend` but we probably shouldn't use this approach anyway. Maybe comments should be attached to nodes somehow? I'm also thinking that maybe the markdown bits should live in the language server.
Thoughts?
Co-authored-by: Jeremy A. Kolb <jkolb@ara.com>
176: Move completio to ra_analysis r=matklad a=matklad
While we should handle completion for isolated file, it's better
achieved by using empty Analysis, rather than working only with &File:
we need memoization for type inference even inside a single file.
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
While we should handle completion for isolated file, it's better
achieved by using empty Analysis, rather than working only with &File:
we need memoization for type inference even inside a single file.
This is a first step towards queryifing completion and resolve.
Some code currently duplicates ra_editor: the plan is to move all
completion from ra_editor, but it'll take more than one commit.
157: Introduce ModuleId r=matklad a=matklad
Previously, module was synonym with a file, and so a module could have
had several parents. This commit introduces a separate module concept,
such that each module has only one parent, but a single file can
correspond to different modules.
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
Previously, module was synonym with a file, and so a module could have
had several parents. This commit introduces a separate module concept,
such that each module has only one parent, but a single file can
correspond to different modules.
156: Cargo Update run r=kjeremy a=kjeremy
Bump relative-path to 0.4.0
Failure 0.1.3 to fix leak with downcast
Updated everything else too
Co-authored-by: Jeremy A. Kolb <jkolb@ara.com>
138: Fix some clippy lints r=matklad a=alanhdu
I went ahead and fixed all the clippy lints (there were a couple I thought would be better unfixed and added `cfg` statements to allow them) and also re-enabled clippy and rustfmt in CI.
They were disabled with `no time to explain, disable clippy checks`, so hopefully this won't go against whatever the reason at the time was 😆.
One question about the CI though: right now, it's an allowed failure that runs against the latest nightly each time. Would it be better to pin it to a specific nightly (or use the `beta` versions) to lower the churn?
Co-authored-by: Alan Du <alanhdu@gmail.com>
143: Implement Find All References and Rename for local variables r=matklad a=kjeremy
Expose `find_all_refs` in `Analysis`. This currently only works for local variables.
Use this in the LSP to implement find all references and rename.
Co-authored-by: Jeremy A. Kolb <jkolb@ara.com>
128: Add a test to verify if the generated codes are up-to-date. r=matklad a=mominul
This test checks if the generated codes are up-to-date every time during `cargo test`.
I have confirmed that the test works by manually editing the `grammar.ron` file.
Closes#126
Thanks!
Co-authored-by: Muhammad Mominul Huque <mominul2082@gmail.com>
127: Improve folding r=matklad a=aochagavia
I was messing around with adding support for multiline comments in folding and ended up changing a bunch of other things.
First of all, I am not convinced of folding groups of successive items. For instance, I don't see why it is worthwhile to be able to fold something like the following:
```rust
use foo;
use bar;
```
Furthermore, this causes problems if you want to fold a multiline import:
```rust
use foo::{
quux
};
use bar;
```
The problem is that now there are two possible folds at the same position: we could fold the first use or we could fold the import group. IMO, the only place where folding groups makes sense is when folding comments. Therefore I have **removed folding import groups in favor of folding multiline imports**.
Regarding folding comments, I made it a bit more robust by requiring that comments can only be folded if they have the same flavor. So if you have a bunch of `//` comments followed by `//!` comments, you will get two separate fold groups instead of a single one.
Finally, I rewrote the API in such a way that it should be trivial to add new folds. You only need to:
* Create a new FoldKind
* Add it to the `fold_kind` function that converts from `SyntaxKind` to `FoldKind`
Fixes#113
Co-authored-by: Adolfo Ochagavía <github@adolfo.ochagavia.xyz>
Implements a pretty barebones function signature help mechanism in
the language server.
Users can use `Analysis::resolve_callback()` to get basic information
about a call site.
Fixes#102
116: Collapse comments upon join r=matklad a=aochagavia
Todo:
- [x] Write tests
- [x] Resolve fixmes
- [x] Implement `comment_start_length` using the parser
I left a bunch of questions as fixmes. Can someone take a look at them? Also, I would love to use the parser to calculate the length of the leading characters in a comment (`//`, `///`, `//!`, `/*`), so any hints are greatly appreciated.
Co-authored-by: Adolfo Ochagavía <aochagavia92@gmail.com>
Co-authored-by: Adolfo Ochagavía <github@adolfo.ochagavia.xyz>
118: Remove error publishing through publishDecorations r=matklad a=aochagavia
The errors are already reported by `publishDiagnostics`
Closes#109
Co-authored-by: Adolfo Ochagavía <aochagavia92@gmail.com>
98: WIP: Add resolve_local_name to resolve names in a function scope r=kjeremy a=kjeremy
First step to resolving #80
Co-authored-by: Jeremy A. Kolb <jkolb@ara.com>
93: Support leading pipe in match arms r=matklad a=DJMcNab
This adds support for match arms of the form:
```rust
<...>
| X | Y => <...>,
| X => <...>,
| 1..2 => <...>,
etc
```
# Implementation discussion
This just naïvely 'eats' a leading pipe if one is available. The equivalent line in the reference `libsyntax` is in [`parse_arm`](441519536c/src/libsyntax/parse/parser.rs (L3552)).
As noted in the comment linked above, this feature was formally introduced as a result of rust-lang/rfcs#1925. This feature is in active use in the [`rust-analyzer` codebase](c87fcb4ea5/crates/ra_syntax/src/syntax_kinds/generated.rs (L231))
I have added some tests for this feature, but maybe more would be required
EDIT: Always looking for feedback - is this PR description over-engineered?
Co-authored-by: Daniel McNab <36049421+djmcnab@users.noreply.github.com>
67: Salsa r=matklad a=matklad
The aim of this PR is to transition from rather ad-hock FileData and ModuleMap caching strategy to something resembling a general-purpose red-green engine.
Ideally, we shouldn't recompute ModuleMap at all, unless the set of mod decls or files changes.
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
69: Incremental reparsing for single tokens r=matklad a=darksv
Implement incremental reparsing for `WHITESPACE`, `COMMENT`, `DOC_COMMENT`, `IDENT`, `STRING` and `RAW_STRING`. This allows to avoid reparsing whole blocks when a change was made only within these tokens.
Co-authored-by: darksv <darek969-12@o2.pl>
This commit is an example of fixing a common parser error: infinite
loop due to error recovery.
This error typically happens when we parse a list of items and fail to
parse a specific item at the current position.
One choices is to skip a token and try to parse a list item at the
next position. This is a good, but not universal, default. When
parsing a list of arguments in a function call, you, for example,
don't want to skip over `fn`, because it's most likely that it is a
function declaration, and not a mistyped arg:
```
fn foo() {
quux(1, 2
fn bar() {
}
```
Another choice is to bail out of the loop immediately, but it isn't
perfect either: sometimes skipping over garbage helps:
```
quux(1, foo:, 92) // should skip over `:`, b/c that's part of `foo::bar`
```
In general, parser tries to balance these two cases, though we don't
have a definitive strategy yet.
However, if the parser accidentally neither skips over a token, nor
breaks out of the loop, then it becomes stuck in the loop infinitely
(there's an internal counter to self-check this situation and panic
though), and that's exactly what is demonstrated by the test.
To fix such situation, first of all, add the test case to tests/data/parser/{err,fuzz-failures}.
Then, run
```
RUST_BACKTRACE=short cargo test --package libsyntax2
````
to verify that parser indeed panics, and to get an idea what grammar
production is the culprit (look for `_list` functions!).
In this case, I see
```
10: libsyntax2::grammar::expressions::atom::match_arm_list
at crates/libsyntax2/src/grammar/expressions/atom.rs:309
```
and that's look like it might be a culprit. I verify it by adding
`eprintln!("loopy {:?}", p.current());` and indeed I see that this is
printed repeatedly.
Diagnosing this a bit shows that the problem is that
`pattern::pattern` function does not consume anything if the next
token is `let`. That is a good default to make cases like
```
let
let foo = 92;
```
where the user hasn't typed the pattern yet, to parse in a reasonable
they correctly.
For match arms, pretty much the single thing we expect is a pattern,
so, for a fix, I introduce a special variant of pattern that does not
do recovery.
As described in #61, fuzz testing some parts of this would be ~~fun~~
helpful. So, I started with the most trivial fuzzer I could think of:
Put random stuff into File::parse and see what happens.
To speed things up, I also did
cp src/**/*.rs fuzz/corpus/parser/
in the `crates/libsyntax2/` directory (running the fuzzer once will
generate the necessary directories).
56: Unify lookahead naming between parser and lexer. r=matklad a=zachlute
Resolves Issue #26.
I wanted to play around with libsyntax2, and fixing a random issue seemed like a good way to mess around in the code.
This PR mostly does what's suggested in that issue. I elected to go with `at` and `at_str` instead of trying to do any fancy overloading shenanigans, because...uh, well, frankly I don't really know how to do any fancy overloading shenanigans. The only really questionable bit is `nth_is_p`, which could also have potentially been named `nth_at_p`, but `is` seemed more apropos.
I also added simple tests for `Ptr` so I could be less terrified I broke something.
Comments and criticisms very welcome. I'm still pretty new to Rust.
Co-authored-by: Zach Lute <zach.lute@gmail.com>
