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-rw-r--r--docs/dev/README.md111
-rw-r--r--docs/dev/architecture.md4
-rw-r--r--docs/dev/debugging.md14
-rw-r--r--docs/dev/guide.md8
-rw-r--r--docs/dev/lsp-extensions.md445
-rw-r--r--docs/dev/lsp-features.md72
-rw-r--r--docs/dev/syntax.md42
7 files changed, 586 insertions, 110 deletions
diff --git a/docs/dev/README.md b/docs/dev/README.md
index f230dc1db..1de5a2aab 100644
--- a/docs/dev/README.md
+++ b/docs/dev/README.md
@@ -30,7 +30,7 @@ https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Fwg-rls-2.2E0
30 30
31* [good-first-issue](https://github.com/rust-analyzer/rust-analyzer/labels/good%20first%20issue) 31* [good-first-issue](https://github.com/rust-analyzer/rust-analyzer/labels/good%20first%20issue)
32 are good issues to get into the project. 32 are good issues to get into the project.
33* [E-mentor](https://github.com/rust-analyzer/rust-analyzer/issues?q=is%3Aopen+is%3Aissue+label%3AE-mentor) 33* [E-has-instructions](https://github.com/rust-analyzer/rust-analyzer/issues?q=is%3Aopen+is%3Aissue+label%3AE-has-instructions)
34 issues have links to the code in question and tests. 34 issues have links to the code in question and tests.
35* [E-easy](https://github.com/rust-analyzer/rust-analyzer/issues?q=is%3Aopen+is%3Aissue+label%3AE-easy), 35* [E-easy](https://github.com/rust-analyzer/rust-analyzer/issues?q=is%3Aopen+is%3Aissue+label%3AE-easy),
36 [E-medium](https://github.com/rust-analyzer/rust-analyzer/issues?q=is%3Aopen+is%3Aissue+label%3AE-medium), 36 [E-medium](https://github.com/rust-analyzer/rust-analyzer/issues?q=is%3Aopen+is%3Aissue+label%3AE-medium),
@@ -74,7 +74,7 @@ relevant test and execute it (VS Code includes an action for running a single
74test). 74test).
75 75
76However, launching a VS Code instance with locally build language server is 76However, launching a VS Code instance with locally build language server is
77possible. There's **"Run Extension (Dev Server)"** launch configuration for this. 77possible. There's **"Run Extension (Debug Build)"** launch configuration for this.
78 78
79In general, I use one of the following workflows for fixing bugs and 79In general, I use one of the following workflows for fixing bugs and
80implementing features. 80implementing features.
@@ -86,7 +86,7 @@ then just do printf-driven development/debugging. As a sanity check after I'm
86done, I use `cargo xtask install --server` and **Reload Window** action in VS 86done, I use `cargo xtask install --server` and **Reload Window** action in VS
87Code to sanity check that the thing works as I expect. 87Code to sanity check that the thing works as I expect.
88 88
89If the problem concerns only the VS Code extension, I use **Run Extension** 89If the problem concerns only the VS Code extension, I use **Run Installed Extension**
90launch configuration from `launch.json`. Notably, this uses the usual 90launch configuration from `launch.json`. Notably, this uses the usual
91`rust-analyzer` binary from `PATH`. For this it is important to have the following 91`rust-analyzer` binary from `PATH`. For this it is important to have the following
92in `setting.json` file: 92in `setting.json` file:
@@ -117,6 +117,109 @@ Additionally, I use `cargo run --release -p rust-analyzer -- analysis-stats
117path/to/some/rust/crate` to run a batch analysis. This is primarily useful for 117path/to/some/rust/crate` to run a batch analysis. This is primarily useful for
118performance optimizations, or for bug minimization. 118performance optimizations, or for bug minimization.
119 119
120# Code Style & Review Process
121
122Our approach to "clean code" is two fold:
123
124* We generally don't block PRs on style changes.
125* At the same time, all code in rust-analyzer is constantly refactored.
126
127It is explicitly OK for reviewer to flag only some nits in the PR, and than send a follow up cleanup PR for things which are easier to explain by example, cc-ing the original author.
128Sending small cleanup PRs (like rename a single local variable) is encouraged.
129
130## Scale of Changes
131
132Everyone knows that it's better to send small & focused pull requests.
133The problem is, sometimes you *have* to, eg, rewrite the whole compiler, and that just doesn't fit into a set of isolated PRs.
134
135The main thing too keep an eye on is the boundaries between various components.
136There are three kinds of changes:
137
1381. Internals of a single component are changed.
139 Specifically, you don't change any `pub` items.
140 A good example here would be an addition of a new assist.
141
1422. API of a component is expanded.
143 Specifically, you add a new `pub` function which wasn't there before.
144 A good example here would be expansion of assist API, for example, to implement lazy assists or assists groups.
145
1463. A new dependency between components is introduced.
147 Specifically, you add a `pub use` reexport from another crate or you add a new line to `[dependencies]` section of `Cargo.toml`.
148 A good example here would be adding reference search capability to the assists crates.
149
150For the first group, the change is generally merged as long as:
151
152* it works for the happy case,
153* it has tests,
154* it doesn't panic for unhappy case.
155
156For the second group, the change would be subjected to quite a bit of scrutiny and iteration.
157The new API needs to be right (or at least easy to change later).
158The actual implementation doesn't matter that much.
159It's very important to minimize the amount of changed lines of code for changes of the second kind.
160Often, you start doing change of the first kind, only to realise that you need to elevate to a change of the second kind.
161In this case, we'll probably ask you to split API changes into a separate PR.
162
163Changes of the third group should be pretty rare, so we don't specify any specific process for them.
164That said, adding an innocent-looking `pub use` is a very simple way to break encapsulation, keep an eye on it!
165
166Note: if you enjoyed this abstract hand-waving about boundaries, you might appreciate
167https://www.tedinski.com/2018/02/06/system-boundaries.html
168
169## Order of Imports
170
171We separate import groups with blank lines
172
173```
174mod x;
175mod y;
176
177use std::{ ... }
178
179use crate_foo::{ ... }
180use crate_bar::{ ... }
181
182use crate::{}
183
184use super::{} // but prefer `use crate::`
185```
186
187## Order of Items
188
189Optimize for the reader who sees the file for the first time, and wants to get the general idea about what's going on.
190People read things from top to bottom, so place most important things first.
191
192Specifically, if all items except one are private, always put the non-private item on top.
193
194Put `struct`s and `enum`s first, functions and impls last.
195
196Do
197
198```
199// Good
200struct Foo {
201 bars: Vec<Bar>
202}
203
204struct Bar;
205```
206
207rather than
208
209```
210// Not as good
211struct Bar;
212
213struct Foo {
214 bars: Vec<Bar>
215}
216```
217
218## Documentation
219
220For `.md` and `.adoc` files, prefer a sentence-per-line format, don't wrap lines.
221If the line is too long, you want to split the sentence in two :-)
222
120# Logging 223# Logging
121 224
122Logging is done by both rust-analyzer and VS Code, so it might be tricky to 225Logging is done by both rust-analyzer and VS Code, so it might be tricky to
@@ -134,7 +237,7 @@ To log all communication between the server and the client, there are two choice
134 237
135* you can log on the server side, by running something like 238* you can log on the server side, by running something like
136 ``` 239 ```
137 env RUST_LOG=gen_lsp_server=trace code . 240 env RA_LOG=gen_lsp_server=trace code .
138 ``` 241 ```
139 242
140* you can log on the client side, by enabling `"rust-analyzer.trace.server": 243* you can log on the client side, by enabling `"rust-analyzer.trace.server":
diff --git a/docs/dev/architecture.md b/docs/dev/architecture.md
index 3a337c574..cee916c09 100644
--- a/docs/dev/architecture.md
+++ b/docs/dev/architecture.md
@@ -46,7 +46,7 @@ can be quickly updated for small modifications.
46 46
47Some of the components of this repository are generated through automatic 47Some of the components of this repository are generated through automatic
48processes. `cargo xtask codegen` runs all generation tasks. Generated code is 48processes. `cargo xtask codegen` runs all generation tasks. Generated code is
49commited to the git repository. 49committed to the git repository.
50 50
51In particular, `cargo xtask codegen` generates: 51In particular, `cargo xtask codegen` generates:
52 52
@@ -114,7 +114,7 @@ is responsible for guessing a HIR for a particular source position.
114Underneath, HIR works on top of salsa, using a `HirDatabase` trait. 114Underneath, HIR works on top of salsa, using a `HirDatabase` trait.
115 115
116`ra_hir_xxx` crates have a strong ECS flavor, in that they work with raw ids and 116`ra_hir_xxx` crates have a strong ECS flavor, in that they work with raw ids and
117directly query the databse. 117directly query the database.
118 118
119The top-level `ra_hir` façade crate wraps ids into a more OO-flavored API. 119The top-level `ra_hir` façade crate wraps ids into a more OO-flavored API.
120 120
diff --git a/docs/dev/debugging.md b/docs/dev/debugging.md
index bece6a572..59a83f7d7 100644
--- a/docs/dev/debugging.md
+++ b/docs/dev/debugging.md
@@ -22,11 +22,11 @@ where **only** the `rust-analyzer` extension being debugged is enabled.
22 22
23## Debug TypeScript VSCode extension 23## Debug TypeScript VSCode extension
24 24
25- `Run Extension` - runs the extension with the globally installed `rust-analyzer` binary. 25- `Run Installed Extension` - runs the extension with the globally installed `rust-analyzer` binary.
26- `Run Extension (Dev Server)` - runs extension with the locally built LSP server (`target/debug/rust-analyzer`). 26- `Run Extension (Debug Build)` - runs extension with the locally built LSP server (`target/debug/rust-analyzer`).
27 27
28TypeScript debugging is configured to watch your source edits and recompile. 28TypeScript debugging is configured to watch your source edits and recompile.
29To apply changes to an already running debug process press <kbd>Ctrl+Shift+P</kbd> and run the following command in your `[Extension Development Host]` 29To apply changes to an already running debug process, press <kbd>Ctrl+Shift+P</kbd> and run the following command in your `[Extension Development Host]`
30 30
31``` 31```
32> Developer: Reload Window 32> Developer: Reload Window
@@ -47,7 +47,7 @@ To apply changes to an already running debug process press <kbd>Ctrl+Shift+P</kb
47 debug = 2 47 debug = 2
48 ``` 48 ```
49 49
50- Select `Run Extension (Dev Server)` to run your locally built `target/debug/rust-analyzer`. 50- Select `Run Extension (Debug Build)` to run your locally built `target/debug/rust-analyzer`.
51 51
52- In the original VSCode window once again select the `Attach To Server` debug configuration. 52- In the original VSCode window once again select the `Attach To Server` debug configuration.
53 53
@@ -76,11 +76,11 @@ Make sure you open a rust file in the `[Extension Development Host]` and try aga
76 76
77Make sure you have run `echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope`. 77Make sure you have run `echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope`.
78 78
79By default this should reset back to 1 everytime you log in. 79By default this should reset back to 1 every time you log in.
80 80
81### Breakpoints are never being hit 81### Breakpoints are never being hit
82 82
83Check your version of `lldb` if it's version 6 and lower use the `classic` adapter type. 83Check your version of `lldb`. If it's version 6 and lower, use the `classic` adapter type.
84It's `lldb.adapterType` in settings file. 84It's `lldb.adapterType` in settings file.
85 85
86If you're running `lldb` version 7 change the lldb adapter type to `bundled` or `native`. 86If you're running `lldb` version 7, change the lldb adapter type to `bundled` or `native`.
diff --git a/docs/dev/guide.md b/docs/dev/guide.md
index abbe4c154..c3252f1f6 100644
--- a/docs/dev/guide.md
+++ b/docs/dev/guide.md
@@ -26,7 +26,7 @@ properties hold:
26 26
27## IDE API 27## IDE API
28 28
29To see the bigger picture of how the IDE features works, let's take a look at the [`AnalysisHost`] and 29To see the bigger picture of how the IDE features work, let's take a look at the [`AnalysisHost`] and
30[`Analysis`] pair of types. `AnalysisHost` has three methods: 30[`Analysis`] pair of types. `AnalysisHost` has three methods:
31 31
32* `default()` for creating an empty analysis instance 32* `default()` for creating an empty analysis instance
@@ -131,7 +131,7 @@ mapping between `SourceRoot` IDs (which are assigned by the client) and actual
131analyzer. 131analyzer.
132 132
133Note that `mod`, `#[path]` and `include!()` can only reference files from the 133Note that `mod`, `#[path]` and `include!()` can only reference files from the
134same source root. It is of course is possible to explicitly add extra files to 134same source root. It is of course possible to explicitly add extra files to
135the source root, even `/dev/random`. 135the source root, even `/dev/random`.
136 136
137## Language Server Protocol 137## Language Server Protocol
@@ -192,7 +192,7 @@ task will be canceled as soon as the main loop calls `apply_change` on the
192[`schedule`]: https://github.com/rust-analyzer/rust-analyzer/blob/guide-2019-01/crates/ra_lsp_server/src/main_loop.rs#L426-L455 192[`schedule`]: https://github.com/rust-analyzer/rust-analyzer/blob/guide-2019-01/crates/ra_lsp_server/src/main_loop.rs#L426-L455
193[The task]: https://github.com/rust-analyzer/rust-analyzer/blob/guide-2019-01/crates/ra_lsp_server/src/main_loop/handlers.rs#L205-L223 193[The task]: https://github.com/rust-analyzer/rust-analyzer/blob/guide-2019-01/crates/ra_lsp_server/src/main_loop/handlers.rs#L205-L223
194 194
195This concludes the overview of the analyzer's programing *interface*. Next, lets 195This concludes the overview of the analyzer's programing *interface*. Next, let's
196dig into the implementation! 196dig into the implementation!
197 197
198## Salsa 198## Salsa
@@ -480,7 +480,7 @@ throughout the analyzer:
480## Source Map pattern 480## Source Map pattern
481 481
482Due to an obscure edge case in completion, IDE needs to know the syntax node of 482Due to an obscure edge case in completion, IDE needs to know the syntax node of
483an use statement which imported the given completion candidate. We can't just 483a use statement which imported the given completion candidate. We can't just
484store the syntax node as a part of name resolution: this will break 484store the syntax node as a part of name resolution: this will break
485incrementality, due to the fact that syntax changes after every file 485incrementality, due to the fact that syntax changes after every file
486modification. 486modification.
diff --git a/docs/dev/lsp-extensions.md b/docs/dev/lsp-extensions.md
new file mode 100644
index 000000000..647cf6107
--- /dev/null
+++ b/docs/dev/lsp-extensions.md
@@ -0,0 +1,445 @@
1# LSP Extensions
2
3This document describes LSP extensions used by rust-analyzer.
4It's a best effort document, when in doubt, consult the source (and send a PR with clarification ;-) ).
5We aim to upstream all non Rust-specific extensions to the protocol, but this is not a top priority.
6All capabilities are enabled via `experimental` field of `ClientCapabilities` or `ServerCapabilities`.
7Requests which we hope to upstream live under `experimental/` namespace.
8Requests, which are likely to always remain specific to `rust-analyzer` are under `rust-analyzer/` namespace.
9
10If you want to be notified about the changes to this document, subscribe to [#4604](https://github.com/rust-analyzer/rust-analyzer/issues/4604).
11
12## `initializationOptions`
13
14As `initializationOptions`, `rust-analyzer` expects `"rust-analyzer"` section of the configuration.
15That is, `rust-analyzer` usually sends `"workspace/configuration"` request with `{ "items": ["rust-analyzer"] }` payload.
16`initializationOptions` should contain the same data that would be in the first item of the result.
17It's OK to not send anything, then all the settings would take their default values.
18However, some settings can not be changed after startup at the moment.
19
20## Snippet `TextEdit`
21
22**Issue:** https://github.com/microsoft/language-server-protocol/issues/724
23
24**Client Capability:** `{ "snippetTextEdit": boolean }`
25
26If this capability is set, `WorkspaceEdit`s returned from `codeAction` requests might contain `SnippetTextEdit`s instead of usual `TextEdit`s:
27
28```typescript
29interface SnippetTextEdit extends TextEdit {
30 insertTextFormat?: InsertTextFormat;
31}
32```
33
34```typescript
35export interface TextDocumentEdit {
36 textDocument: VersionedTextDocumentIdentifier;
37 edits: (TextEdit | SnippetTextEdit)[];
38}
39```
40
41When applying such code action, the editor should insert snippet, with tab stops and placeholder.
42At the moment, rust-analyzer guarantees that only a single edit will have `InsertTextFormat.Snippet`.
43
44### Example
45
46"Add `derive`" code action transforms `struct S;` into `#[derive($0)] struct S;`
47
48### Unresolved Questions
49
50* Where exactly are `SnippetTextEdit`s allowed (only in code actions at the moment)?
51* Can snippets span multiple files (so far, no)?
52
53## `CodeAction` Groups
54
55**Issue:** https://github.com/microsoft/language-server-protocol/issues/994
56
57**Client Capability:** `{ "codeActionGroup": boolean }`
58
59If this capability is set, `CodeAction` returned from the server contain an additional field, `group`:
60
61```typescript
62interface CodeAction {
63 title: string;
64 group?: string;
65 ...
66}
67```
68
69All code-actions with the same `group` should be grouped under single (extendable) entry in lightbulb menu.
70The set of actions `[ { title: "foo" }, { group: "frobnicate", title: "bar" }, { group: "frobnicate", title: "baz" }]` should be rendered as
71
72```
73💡
74 +-------------+
75 | foo |
76 +-------------+-----+
77 | frobnicate >| bar |
78 +-------------+-----+
79 | baz |
80 +-----+
81```
82
83Alternatively, selecting `frobnicate` could present a user with an additional menu to choose between `bar` and `baz`.
84
85### Example
86
87```rust
88fn main() {
89 let x: Entry/*cursor here*/ = todo!();
90}
91```
92
93Invoking code action at this position will yield two code actions for importing `Entry` from either `collections::HashMap` or `collection::BTreeMap`, grouped under a single "import" group.
94
95### Unresolved Questions
96
97* Is a fixed two-level structure enough?
98* Should we devise a general way to encode custom interaction protocols for GUI refactorings?
99
100## Parent Module
101
102**Issue:** https://github.com/microsoft/language-server-protocol/issues/1002
103
104**Server Capability:** `{ "parentModule": boolean }`
105
106This request is send from client to server to handle "Goto Parent Module" editor action.
107
108**Method:** `experimental/parentModule`
109
110**Request:** `TextDocumentPositionParams`
111
112**Response:** `Location | Location[] | LocationLink[] | null`
113
114
115### Example
116
117```rust
118// src/main.rs
119mod foo;
120// src/foo.rs
121
122/* cursor here*/
123```
124
125`experimental/parentModule` returns a single `Link` to the `mod foo;` declaration.
126
127### Unresolved Question
128
129* An alternative would be to use a more general "gotoSuper" request, which would work for super methods, super classes and super modules.
130 This is the approach IntelliJ Rust is takeing.
131 However, experience shows that super module (which generally has a feeling of navigation between files) should be separate.
132 If you want super module, but the cursor happens to be inside an overriden function, the behavior with single "gotoSuper" request is surprising.
133
134## Join Lines
135
136**Issue:** https://github.com/microsoft/language-server-protocol/issues/992
137
138**Server Capability:** `{ "joinLines": boolean }`
139
140This request is send from client to server to handle "Join Lines" editor action.
141
142**Method:** `experimental/joinLines`
143
144**Request:**
145
146```typescript
147interface JoinLinesParams {
148 textDocument: TextDocumentIdentifier,
149 /// Currently active selections/cursor offsets.
150 /// This is an array to support multiple cursors.
151 ranges: Range[],
152}
153```
154
155**Response:** `TextEdit[]`
156
157### Example
158
159```rust
160fn main() {
161 /*cursor here*/let x = {
162 92
163 };
164}
165```
166
167`experimental/joinLines` yields (curly braces are automagically removed)
168
169```rust
170fn main() {
171 let x = 92;
172}
173```
174
175### Unresolved Question
176
177* What is the position of the cursor after `joinLines`?
178 Currently this is left to editor's discretion, but it might be useful to specify on the server via snippets.
179 However, it then becomes unclear how it works with multi cursor.
180
181## On Enter
182
183**Issue:** https://github.com/microsoft/language-server-protocol/issues/1001
184
185**Server Capability:** `{ "onEnter": boolean }`
186
187This request is send from client to server to handle <kbd>Enter</kbd> keypress.
188
189**Method:** `experimental/onEnter`
190
191**Request:**: `TextDocumentPositionParams`
192
193**Response:**
194
195```typescript
196SnippetTextEdit[]
197```
198
199### Example
200
201```rust
202fn main() {
203 // Some /*cursor here*/ docs
204 let x = 92;
205}
206```
207
208`experimental/onEnter` returns the following snippet
209
210```rust
211fn main() {
212 // Some
213 // $0 docs
214 let x = 92;
215}
216```
217
218The primary goal of `onEnter` is to handle automatic indentation when opening a new line.
219This is not yet implemented.
220The secondary goal is to handle fixing up syntax, like continuing doc strings and comments, and escaping `\n` in string literals.
221
222As proper cursor positioning is raison-d'etat for `onEnter`, it uses `SnippetTextEdit`.
223
224### Unresolved Question
225
226* How to deal with synchronicity of the request?
227 One option is to require the client to block until the server returns the response.
228 Another option is to do a OT-style merging of edits from client and server.
229 A third option is to do a record-replay: client applies heuristic on enter immediatelly, then applies all user's keypresses.
230 When the server is ready with the response, the client rollbacks all the changes and applies the recorded actions on top of the correct response.
231* How to deal with multiple carets?
232* Should we extend this to arbitrary typed events and not just `onEnter`?
233
234## Structural Search Replace (SSR)
235
236**Server Capability:** `{ "ssr": boolean }`
237
238This request is send from client to server to handle structural search replace -- automated syntax tree based transformation of the source.
239
240**Method:** `experimental/ssr`
241
242**Request:**
243
244```typescript
245interface SsrParams {
246 /// Search query.
247 /// The specific syntax is specified outside of the protocol.
248 query: string,
249 /// If true, only check the syntax of the query and don't compute the actual edit.
250 parseOnly: bool,
251}
252```
253
254**Response:**
255
256```typescript
257WorkspaceEdit
258```
259
260### Example
261
262SSR with query `foo($a:expr, $b:expr) ==>> ($a).foo($b)` will transform, eg `foo(y + 5, z)` into `(y + 5).foo(z)`.
263
264### Unresolved Question
265
266* Probably needs search without replace mode
267* Needs a way to limit the scope to certain files.
268
269## Matching Brace
270
271**Issue:** https://github.com/microsoft/language-server-protocol/issues/999
272
273**Server Capability:** `{ "matchingBrace": boolean }`
274
275This request is send from client to server to handle "Matching Brace" editor action.
276
277**Method:** `experimental/matchingBrace`
278
279**Request:**
280
281```typescript
282interface MatchingBraceParams {
283 textDocument: TextDocumentIdentifier,
284 /// Position for each cursor
285 positions: Position[],
286}
287```
288
289**Response:**
290
291```typescript
292Position[]
293```
294
295### Example
296
297```rust
298fn main() {
299 let x: Vec<()>/*cursor here*/ = vec![]
300}
301```
302
303`experimental/matchingBrace` yields the position of `<`.
304In many cases, matching braces can be handled by the editor.
305However, some cases (like disambiguating between generics and comparison operations) need a real parser.
306Moreover, it would be cool if editors didn't need to implement even basic language parsing
307
308### Unresolved Question
309
310* Should we return a a nested brace structure, to allow paredit-like actions of jump *out* of the current brace pair?
311 This is how `SelectionRange` request works.
312* Alternatively, should we perhaps flag certain `SelectionRange`s as being brace pairs?
313
314## Runnables
315
316**Issue:** https://github.com/microsoft/language-server-protocol/issues/944
317
318**Server Capability:** `{ "runnables": { "kinds": string[] } }`
319
320This request is send from client to server to get the list of things that can be run (tests, binaries, `cargo check -p`).
321
322**Method:** `experimental/runnables`
323
324**Request:**
325
326```typescript
327interface RunnablesParams {
328 textDocument: TextDocumentIdentifier;
329 /// If null, compute runnables for the whole file.
330 position?: Position;
331}
332```
333
334**Response:** `Runnable[]`
335
336```typescript
337interface Runnable {
338 label: string;
339 /// If this Runnable is associated with a specific function/module, etc, the location of this item
340 location?: LocationLink;
341 /// Running things is necessary technology specific, `kind` needs to be advertised via server capabilities,
342 // the type of `args` is specific to `kind`. The actual running is handled by the client.
343 kind: string;
344 args: any;
345}
346```
347
348rust-analyzer supports only one `kind`, `"cargo"`. The `args` for `"cargo"` look like this:
349
350```typescript
351{
352 workspaceRoot?: string;
353 cargoArgs: string[];
354 executableArgs: string[];
355}
356```
357
358## Analyzer Status
359
360**Method:** `rust-analyzer/analyzerStatus`
361
362**Request:** `null`
363
364**Response:** `string`
365
366Returns internal status message, mostly for debugging purposes.
367
368## Collect Garbage
369
370**Method:** `rust-analyzer/collectGarbage`
371
372**Request:** `null`
373
374**Response:** `null`
375
376Frees some caches. For internal use, and is mostly broken at the moment.
377
378## Syntax Tree
379
380**Method:** `rust-analyzer/syntaxTree`
381
382**Request:**
383
384```typescript
385interface SyntaxTeeParams {
386 textDocument: TextDocumentIdentifier,
387 range?: Range,
388}
389```
390
391**Response:** `string`
392
393Returns textual representation of a parse tree for the file/selected region.
394Primarily for debugging, but very useful for all people working on rust-analyzer itself.
395
396## Expand Macro
397
398**Method:** `rust-analyzer/expandMacro`
399
400**Request:**
401
402```typescript
403interface ExpandMacroParams {
404 textDocument: TextDocumentIdentifier,
405 position: Position,
406}
407```
408
409**Response:**
410
411```typescript
412interface ExpandedMacro {
413 name: string,
414 expansion: string,
415}
416```
417
418Expands macro call at a given position.
419
420## Inlay Hints
421
422**Method:** `rust-analyzer/inlayHints`
423
424This request is send from client to server to render "inlay hints" -- virtual text inserted into editor to show things like inferred types.
425Generally, the client should re-query inlay hints after every modification.
426Note that we plan to move this request to `experimental/inlayHints`, as it is not really Rust-specific, but the current API is not necessary the right one.
427Upstream issue: https://github.com/microsoft/language-server-protocol/issues/956
428
429**Request:**
430
431```typescript
432interface InlayHintsParams {
433 textDocument: TextDocumentIdentifier,
434}
435```
436
437**Response:** `InlayHint[]`
438
439```typescript
440interface InlayHint {
441 kind: "TypeHint" | "ParameterHint" | "ChainingHint",
442 range: Range,
443 label: string,
444}
445```
diff --git a/docs/dev/lsp-features.md b/docs/dev/lsp-features.md
deleted file mode 100644
index 00b0867d7..000000000
--- a/docs/dev/lsp-features.md
+++ /dev/null
@@ -1,72 +0,0 @@
1# Supported LSP features
2
3This list documents LSP features, supported by rust-analyzer.
4
5## General
6- [x] [initialize](https://microsoft.github.io/language-server-protocol/specification#initialize)
7- [x] [initialized](https://microsoft.github.io/language-server-protocol/specification#initialized)
8- [x] [shutdown](https://microsoft.github.io/language-server-protocol/specification#shutdown)
9- [ ] [exit](https://microsoft.github.io/language-server-protocol/specification#exit)
10- [x] [$/cancelRequest](https://microsoft.github.io/language-server-protocol/specification#cancelRequest)
11
12## Workspace
13- [ ] [workspace/workspaceFolders](https://microsoft.github.io/language-server-protocol/specification#workspace_workspaceFolders)
14- [ ] [workspace/didChangeWorkspaceFolders](https://microsoft.github.io/language-server-protocol/specification#workspace_didChangeWorkspaceFolders)
15- [x] [workspace/didChangeConfiguration](https://microsoft.github.io/language-server-protocol/specification#workspace_didChangeConfiguration)
16- [ ] [workspace/configuration](https://microsoft.github.io/language-server-protocol/specification#workspace_configuration)
17- [x] [workspace/didChangeWatchedFiles](https://microsoft.github.io/language-server-protocol/specification#workspace_didChangeWatchedFiles)
18- [x] [workspace/symbol](https://microsoft.github.io/language-server-protocol/specification#workspace_symbol)
19- [ ] [workspace/applyEdit](https://microsoft.github.io/language-server-protocol/specification#workspace_applyEdit)
20
21## Text Synchronization
22- [x] [textDocument/didOpen](https://microsoft.github.io/language-server-protocol/specification#textDocument_didOpen)
23- [x] [textDocument/didChange](https://microsoft.github.io/language-server-protocol/specification#textDocument_didChange)
24- [ ] [textDocument/willSave](https://microsoft.github.io/language-server-protocol/specification#textDocument_willSave)
25- [ ] [textDocument/willSaveWaitUntil](https://microsoft.github.io/language-server-protocol/specification#textDocument_willSaveWaitUntil)
26- [x] [textDocument/didSave](https://microsoft.github.io/language-server-protocol/specification#textDocument_didSave)
27- [x] [textDocument/didClose](https://microsoft.github.io/language-server-protocol/specification#textDocument_didClose)
28
29## Diagnostics
30- [x] [textDocument/publishDiagnostics](https://microsoft.github.io/language-server-protocol/specification#textDocument_publishDiagnostics)
31
32## Lanuguage Features
33- [x] [textDocument/completion](https://microsoft.github.io/language-server-protocol/specification#textDocument_completion)
34 - open close: false
35 - change: Full
36 - will save: false
37 - will save wait until: false
38 - save: false
39- [x] [completionItem/resolve](https://microsoft.github.io/language-server-protocol/specification#completionItem_resolve)
40 - resolve provider: none
41 - trigger characters: `:`, `.`
42- [x] [textDocument/hover](https://microsoft.github.io/language-server-protocol/specification#textDocument_hover)
43- [x] [textDocument/signatureHelp](https://microsoft.github.io/language-server-protocol/specification#textDocument_signatureHelp)
44 - trigger characters: `(`, `,`
45- [ ] [textDocument/declaration](https://microsoft.github.io/language-server-protocol/specification#textDocument_declaration)
46- [x] [textDocument/definition](https://microsoft.github.io/language-server-protocol/specification#textDocument_definition)
47- [x] [textDocument/typeDefinition](https://microsoft.github.io/language-server-protocol/specification#textDocument_typeDefinition)
48- [x] [textDocument/implementation](https://microsoft.github.io/language-server-protocol/specification#textDocument_implementation)
49- [x] [textDocument/references](https://microsoft.github.io/language-server-protocol/specification#textDocument_references)
50- [x] [textDocument/documentHighlight](https://microsoft.github.io/language-server-protocol/specification#textDocument_documentHighlight)
51- [x] [textDocument/documentSymbol](https://microsoft.github.io/language-server-protocol/specification#textDocument_documentSymbol)
52- [x] [textDocument/codeAction](https://microsoft.github.io/language-server-protocol/specification#textDocument_codeAction)
53- [x] [textDocument/selectionRange](https://github.com/Microsoft/language-server-protocol/issues/613)
54 - rust-analyzer.syntaxTree
55 - rust-analyzer.matchingBrace
56 - rust-analyzer.parentModule
57 - rust-analyzer.joinLines
58 - rust-analyzer.run
59 - rust-analyzer.analyzerStatus
60- [x] [textDocument/codeLens](https://microsoft.github.io/language-server-protocol/specification#textDocument_codeLens)
61- [x] [codeLens/resolve](https://microsoft.github.io/language-server-protocol/specification#codeLens_resolve)
62- [ ] [documentLink/resolve](https://microsoft.github.io/language-server-protocol/specification#documentLink_resolve)
63- [ ] [textDocument/documentColor](https://microsoft.github.io/language-server-protocol/specification#textDocument_documentColor)
64- [ ] [textDocument/colorPresentation](https://microsoft.github.io/language-server-protocol/specification#textDocument_colorPresentation)
65- [x] [textDocument/formatting](https://microsoft.github.io/language-server-protocol/specification#textDocument_formatting)
66- [ ] [textDocument/rangeFormatting](https://microsoft.github.io/language-server-protocol/specification#textDocument_rangeFormatting)
67- [x] [textDocument/onTypeFormatting](https://microsoft.github.io/language-server-protocol/specification#textDocument_onTypeFormatting)
68 - first trigger character: `=`
69 - more trigger character `.`
70- [x] [textDocument/rename](https://microsoft.github.io/language-server-protocol/specification#textDocument_rename)
71- [x] [textDocument/prepareRename](https://microsoft.github.io/language-server-protocol/specification#textDocument_prepareRename)
72- [x] [textDocument/foldingRange](https://microsoft.github.io/language-server-protocol/specification#textDocument_foldingRange)
diff --git a/docs/dev/syntax.md b/docs/dev/syntax.md
index 33973ffec..c2864bbbc 100644
--- a/docs/dev/syntax.md
+++ b/docs/dev/syntax.md
@@ -64,7 +64,7 @@ struct Token {
64} 64}
65``` 65```
66 66
67All the difference bettwen the above sketch and the real implementation are strictly due to optimizations. 67All the difference between the above sketch and the real implementation are strictly due to optimizations.
68 68
69Points of note: 69Points of note:
70* The tree is untyped. Each node has a "type tag", `SyntaxKind`. 70* The tree is untyped. Each node has a "type tag", `SyntaxKind`.
@@ -72,7 +72,7 @@ Points of note:
72* Trivia and non-trivia tokens are not distinguished on the type level. 72* Trivia and non-trivia tokens are not distinguished on the type level.
73* Each token carries its full text. 73* Each token carries its full text.
74* The original text can be recovered by concatenating the texts of all tokens in order. 74* The original text can be recovered by concatenating the texts of all tokens in order.
75* Accessing a child of particular type (for example, parameter list of a function) generarly involves linerary traversing the children, looking for a specific `kind`. 75* Accessing a child of particular type (for example, parameter list of a function) generally involves linerary traversing the children, looking for a specific `kind`.
76* Modifying the tree is roughly `O(depth)`. 76* Modifying the tree is roughly `O(depth)`.
77 We don't make special efforts to guarantree that the depth is not liner, but, in practice, syntax trees are branchy and shallow. 77 We don't make special efforts to guarantree that the depth is not liner, but, in practice, syntax trees are branchy and shallow.
78* If mandatory (grammar wise) node is missing from the input, it's just missing from the tree. 78* If mandatory (grammar wise) node is missing from the input, it's just missing from the tree.
@@ -123,7 +123,7 @@ To more compactly store the children, we box *both* interior nodes and tokens, a
123`Either<Arc<Node>, Arc<Token>>` as a single pointer with a tag in the last bit. 123`Either<Arc<Node>, Arc<Token>>` as a single pointer with a tag in the last bit.
124 124
125To avoid allocating EVERY SINGLE TOKEN on the heap, syntax trees use interning. 125To avoid allocating EVERY SINGLE TOKEN on the heap, syntax trees use interning.
126Because the tree is fully imutable, it's valid to structuraly share subtrees. 126Because the tree is fully immutable, it's valid to structurally share subtrees.
127For example, in `1 + 1`, there will be a *single* token for `1` with ref count 2; the same goes for the ` ` whitespace token. 127For example, in `1 + 1`, there will be a *single* token for `1` with ref count 2; the same goes for the ` ` whitespace token.
128Interior nodes are shared as well (for example in `(1 + 1) * (1 + 1)`). 128Interior nodes are shared as well (for example in `(1 + 1) * (1 + 1)`).
129 129
@@ -134,8 +134,8 @@ Currently, the interner is created per-file, but it will be easy to use a per-th
134 134
135We use a `TextSize`, a newtyped `u32`, to store the length of the text. 135We use a `TextSize`, a newtyped `u32`, to store the length of the text.
136 136
137We currently use `SmolStr`, an small object optimized string to store text. 137We currently use `SmolStr`, a small object optimized string to store text.
138This was mostly relevant *before* we implmented tree interning, to avoid allocating common keywords and identifiers. We should switch to storing text data alongside the interned tokens. 138This was mostly relevant *before* we implemented tree interning, to avoid allocating common keywords and identifiers. We should switch to storing text data alongside the interned tokens.
139 139
140#### Alternative designs 140#### Alternative designs
141 141
@@ -162,12 +162,12 @@ Explicit trivia nodes, like in `rowan`, are used by IntelliJ.
162 162
163##### Accessing Children 163##### Accessing Children
164 164
165As noted before, accesing a specific child in the node requires a linear traversal of the children (though we can skip tokens, beacuse the tag is encoded in the pointer itself). 165As noted before, accessing a specific child in the node requires a linear traversal of the children (though we can skip tokens, because the tag is encoded in the pointer itself).
166It is possible to recover O(1) access with another representation. 166It is possible to recover O(1) access with another representation.
167We explicitly store optional and missing (required by the grammar, but not present) nodes. 167We explicitly store optional and missing (required by the grammar, but not present) nodes.
168That is, we use `Option<Node>` for children. 168That is, we use `Option<Node>` for children.
169We also remove trivia tokens from the tree. 169We also remove trivia tokens from the tree.
170This way, each child kind genrerally occupies a fixed position in a parent, and we can use index access to fetch it. 170This way, each child kind generally occupies a fixed position in a parent, and we can use index access to fetch it.
171The cost is that we now need to allocate space for all not-present optional nodes. 171The cost is that we now need to allocate space for all not-present optional nodes.
172So, `fn foo() {}` will have slots for visibility, unsafeness, attributes, abi and return type. 172So, `fn foo() {}` will have slots for visibility, unsafeness, attributes, abi and return type.
173 173
@@ -193,7 +193,7 @@ Modeling this with immutable trees is possible, but annoying.
193### Syntax Nodes 193### Syntax Nodes
194 194
195A function green tree is not super-convenient to use. 195A function green tree is not super-convenient to use.
196The biggest problem is acessing parents (there are no parent pointers!). 196The biggest problem is accessing parents (there are no parent pointers!).
197But there are also "identify" issues. 197But there are also "identify" issues.
198Let's say you want to write a code which builds a list of expressions in a file: `fn collect_exrepssions(file: GreenNode) -> HashSet<GreenNode>`. 198Let's say you want to write a code which builds a list of expressions in a file: `fn collect_exrepssions(file: GreenNode) -> HashSet<GreenNode>`.
199For the input like 199For the input like
@@ -207,7 +207,7 @@ fn main() {
207} 207}
208``` 208```
209 209
210both copies of the `x + 2` expression are representing by equal (and, with interning in mind, actualy the same) green nodes. 210both copies of the `x + 2` expression are representing by equal (and, with interning in mind, actually the same) green nodes.
211Green trees just can't differentiate between the two. 211Green trees just can't differentiate between the two.
212 212
213`SyntaxNode` adds parent pointers and identify semantics to green nodes. 213`SyntaxNode` adds parent pointers and identify semantics to green nodes.
@@ -285,9 +285,9 @@ They also point to the parent (and, consequently, to the root) with an owning `R
285In other words, one needs *one* arc bump when initiating a traversal. 285In other words, one needs *one* arc bump when initiating a traversal.
286 286
287To get rid of allocations, `rowan` takes advantage of `SyntaxNode: !Sync` and uses a thread-local free list of `SyntaxNode`s. 287To get rid of allocations, `rowan` takes advantage of `SyntaxNode: !Sync` and uses a thread-local free list of `SyntaxNode`s.
288In a typical traversal, you only directly hold a few `SyntaxNode`s at a time (and their ancesstors indirectly), so a free list proportional to the depth of the tree removes all allocations in a typical case. 288In a typical traversal, you only directly hold a few `SyntaxNode`s at a time (and their ancestors indirectly), so a free list proportional to the depth of the tree removes all allocations in a typical case.
289 289
290So, while traversal is not exactly incrementing a pointer, it's still prety cheep: tls + rc bump! 290So, while traversal is not exactly incrementing a pointer, it's still pretty cheap: TLS + rc bump!
291 291
292Traversal also yields (cheap) owned nodes, which improves ergonomics quite a bit. 292Traversal also yields (cheap) owned nodes, which improves ergonomics quite a bit.
293 293
@@ -308,15 +308,15 @@ struct SyntaxData {
308} 308}
309``` 309```
310 310
311This allows using true pointer equality for comparision of identities of `SyntaxNodes`. 311This allows using true pointer equality for comparison of identities of `SyntaxNodes`.
312rust-analyzer used to have this design as well, but since we've switch to cursors. 312rust-analyzer used to have this design as well, but we've since switched to cursors.
313The main problem with memoizing the red nodes is that it more than doubles the memory requirenments for fully realized syntax trees. 313The main problem with memoizing the red nodes is that it more than doubles the memory requirements for fully realized syntax trees.
314In contrast, cursors generally retain only a path to the root. 314In contrast, cursors generally retain only a path to the root.
315C# combats increased memory usage by using weak references. 315C# combats increased memory usage by using weak references.
316 316
317### AST 317### AST
318 318
319`GreenTree`s are untyped and homogeneous, because it makes accomodating error nodes, arbitrary whitespace and comments natural, and because it makes possible to write generic tree traversals. 319`GreenTree`s are untyped and homogeneous, because it makes accommodating error nodes, arbitrary whitespace and comments natural, and because it makes possible to write generic tree traversals.
320However, when working with a specific node, like a function definition, one would want a strongly typed API. 320However, when working with a specific node, like a function definition, one would want a strongly typed API.
321 321
322This is what is provided by the AST layer. AST nodes are transparent wrappers over untyped syntax nodes: 322This is what is provided by the AST layer. AST nodes are transparent wrappers over untyped syntax nodes:
@@ -397,7 +397,7 @@ impl HasVisbility for FnDef {
397Points of note: 397Points of note:
398 398
399* Like `SyntaxNode`s, AST nodes are cheap to clone pointer-sized owned values. 399* Like `SyntaxNode`s, AST nodes are cheap to clone pointer-sized owned values.
400* All "fields" are optional, to accomodate incomplete and/or erroneous source code. 400* All "fields" are optional, to accommodate incomplete and/or erroneous source code.
401* It's always possible to go from an ast node to an untyped `SyntaxNode`. 401* It's always possible to go from an ast node to an untyped `SyntaxNode`.
402* It's possible to go in the opposite direction with a checked cast. 402* It's possible to go in the opposite direction with a checked cast.
403* `enum`s allow modeling of arbitrary intersecting subsets of AST types. 403* `enum`s allow modeling of arbitrary intersecting subsets of AST types.
@@ -437,13 +437,13 @@ impl GreenNodeBuilder {
437} 437}
438``` 438```
439 439
440The parser, ultimatelly, needs to invoke the `GreenNodeBuilder`. 440The parser, ultimately, needs to invoke the `GreenNodeBuilder`.
441There are two principal sources of inputs for the parser: 441There are two principal sources of inputs for the parser:
442 * source text, which contains trivia tokens (whitespace and comments) 442 * source text, which contains trivia tokens (whitespace and comments)
443 * token trees from macros, which lack trivia 443 * token trees from macros, which lack trivia
444 444
445Additionaly, input tokens do not correspond 1-to-1 with output tokens. 445Additionally, input tokens do not correspond 1-to-1 with output tokens.
446For example, two consequtive `>` tokens might be glued, by the parser, into a single `>>`. 446For example, two consecutive `>` tokens might be glued, by the parser, into a single `>>`.
447 447
448For these reasons, the parser crate defines a callback interfaces for both input tokens and output trees. 448For these reasons, the parser crate defines a callback interfaces for both input tokens and output trees.
449The explicit glue layer then bridges various gaps. 449The explicit glue layer then bridges various gaps.
@@ -491,7 +491,7 @@ Syntax errors are not stored directly in the tree.
491The primary motivation for this is that syntax tree is not necessary produced by the parser, it may also be assembled manually from pieces (which happens all the time in refactorings). 491The primary motivation for this is that syntax tree is not necessary produced by the parser, it may also be assembled manually from pieces (which happens all the time in refactorings).
492Instead, parser reports errors to an error sink, which stores them in a `Vec`. 492Instead, parser reports errors to an error sink, which stores them in a `Vec`.
493If possible, errors are not reported during parsing and are postponed for a separate validation step. 493If possible, errors are not reported during parsing and are postponed for a separate validation step.
494For example, parser accepts visibility modifiers on trait methods, but then a separate tree traversal flags all such visibilites as erroneous. 494For example, parser accepts visibility modifiers on trait methods, but then a separate tree traversal flags all such visibilities as erroneous.
495 495
496### Macros 496### Macros
497 497
@@ -501,7 +501,7 @@ Specifically, `TreeSink` constructs the tree in lockstep with draining the origi
501In the process, it records which tokens of the tree correspond to which tokens of the input, by using text ranges to identify syntax tokens. 501In the process, it records which tokens of the tree correspond to which tokens of the input, by using text ranges to identify syntax tokens.
502The end result is that parsing an expanded code yields a syntax tree and a mapping of text-ranges of the tree to original tokens. 502The end result is that parsing an expanded code yields a syntax tree and a mapping of text-ranges of the tree to original tokens.
503 503
504To deal with precedence in cases like `$expr * 1`, we use special invisible parenthesis, which are explicitelly handled by the parser 504To deal with precedence in cases like `$expr * 1`, we use special invisible parenthesis, which are explicitly handled by the parser
505 505
506### Whitespace & Comments 506### Whitespace & Comments
507 507