feat: Implement diagnostics pull model

crates/rust-analyzer/src/diagnostics.rs

@@ -173,21 +173,6 @@ pub(crate) fn fetch_native_diagnostics(
     let _p = tracing::info_span!("fetch_native_diagnostics").entered();
     let _ctx = stdx::panic_context::enter("fetch_native_diagnostics".to_owned());
 
-    let convert_diagnostic =
-        |line_index: &crate::line_index::LineIndex, d: ide::Diagnostic| lsp_types::Diagnostic {
-            range: lsp::to_proto::range(line_index, d.range.range),
-            severity: Some(lsp::to_proto::diagnostic_severity(d.severity)),
-            code: Some(lsp_types::NumberOrString::String(d.code.as_str().to_owned())),
-            code_description: Some(lsp_types::CodeDescription {
-                href: lsp_types::Url::parse(&d.code.url()).unwrap(),
-            }),
-            source: Some("rust-analyzer".to_owned()),
-            message: d.message,
-            related_information: None,
-            tags: d.unused.then(|| vec![lsp_types::DiagnosticTag::UNNECESSARY]),
-            data: None,
-        };
-
     // the diagnostics produced may point to different files not requested by the concrete request,
     // put those into here and filter later
     let mut odd_ones = Vec::new();
@@ -246,3 +231,22 @@ pub(crate) fn fetch_native_diagnostics(
     }
     diagnostics
 }
+
+pub(crate) fn convert_diagnostic(
+    line_index: &crate::line_index::LineIndex,
+    d: ide::Diagnostic,
+) -> lsp_types::Diagnostic {
+    lsp_types::Diagnostic {
+        range: lsp::to_proto::range(line_index, d.range.range),
+        severity: Some(lsp::to_proto::diagnostic_severity(d.severity)),
+        code: Some(lsp_types::NumberOrString::String(d.code.as_str().to_owned())),
+        code_description: Some(lsp_types::CodeDescription {
+            href: lsp_types::Url::parse(&d.code.url()).unwrap(),
+        }),
+        source: Some("rust-analyzer".to_owned()),
+        message: d.message,
+        related_information: None,
+        tags: d.unused.then(|| vec![lsp_types::DiagnosticTag::UNNECESSARY]),
+        data: None,
+    }
+}

crates/rust-analyzer/src/handlers/dispatch.rs

@@ -120,6 +120,30 @@ impl RequestDispatcher<'_> {
         self.on_with_thread_intent::<true, ALLOW_RETRYING, R>(ThreadIntent::Worker, f)
     }
 
+    /// Dispatches a non-latency-sensitive request onto the thread pool. When the VFS is marked not
+    /// ready this will return a default constructed [`R::Result`].
+    pub(crate) fn on_or<const ALLOW_RETRYING: bool, R>(
+        &mut self,
+        f: fn(GlobalStateSnapshot, R::Params) -> anyhow::Result<R::Result>,
+        default: impl FnOnce() -> R::Result,
+    ) -> &mut Self
+    where
+        R: lsp_types::request::Request<
+                Params: DeserializeOwned + panic::UnwindSafe + Send + fmt::Debug,
+                Result: Serialize,
+            > + 'static,
+    {
+        if !self.global_state.vfs_done {
+            if let Some(lsp_server::Request { id, .. }) =
+                self.req.take_if(|it| it.method == R::METHOD)
+            {
+                self.global_state.respond(lsp_server::Response::new_ok(id, default()));
+            }
+            return self;
+        }
+        self.on_with_thread_intent::<true, ALLOW_RETRYING, R>(ThreadIntent::Worker, f)
+    }
+
     /// Dispatches a non-latency-sensitive request onto the thread pool. When the VFS is marked not
     /// ready this will return the parameter as is.
     pub(crate) fn on_identity<const ALLOW_RETRYING: bool, R, Params>(

crates/rust-analyzer/src/handlers/request.rs

@@ -4,6 +4,7 @@
 use std::{
     fs,
     io::Write as _,
+    ops::Not,
     process::{self, Stdio},
 };
 
@@ -14,7 +15,7 @@ use ide::{
     FilePosition, FileRange, HoverAction, HoverGotoTypeData, InlayFieldsToResolve, Query,
     RangeInfo, ReferenceCategory, Runnable, RunnableKind, SingleResolve, SourceChange, TextEdit,
 };
-use ide_db::SymbolKind;
+use ide_db::{FxHashMap, SymbolKind};
 use itertools::Itertools;
 use lsp_server::ErrorCode;
 use lsp_types::{
@@ -36,6 +37,7 @@ use vfs::{AbsPath, AbsPathBuf, FileId, VfsPath};
 
 use crate::{
     config::{Config, RustfmtConfig, WorkspaceSymbolConfig},
+    diagnostics::convert_diagnostic,
     global_state::{FetchWorkspaceRequest, GlobalState, GlobalStateSnapshot},
     hack_recover_crate_name,
     line_index::LineEndings,
@@ -473,6 +475,68 @@ pub(crate) fn handle_on_type_formatting(
     Ok(Some(change))
 }
 
+pub(crate) fn handle_document_diagnostics(
+    snap: GlobalStateSnapshot,
+    params: lsp_types::DocumentDiagnosticParams,
+) -> anyhow::Result<lsp_types::DocumentDiagnosticReportResult> {
+    let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
+    let source_root = snap.analysis.source_root_id(file_id)?;
+    let line_index = snap.file_line_index(file_id)?;
+    let config = snap.config.diagnostics(Some(source_root));
+    if !config.enabled {
+        return Ok(lsp_types::DocumentDiagnosticReportResult::Report(
+            lsp_types::DocumentDiagnosticReport::Full(
+                lsp_types::RelatedFullDocumentDiagnosticReport {
+                    related_documents: None,
+                    full_document_diagnostic_report: lsp_types::FullDocumentDiagnosticReport {
+                        result_id: None,
+                        items: vec![],
+                    },
+                },
+            ),
+        ));
+    }
+    let supports_related = snap.config.text_document_diagnostic_related_document_support();
+
+    let mut related_documents = FxHashMap::default();
+    let diagnostics = snap
+        .analysis
+        .full_diagnostics(&config, AssistResolveStrategy::None, file_id)?
+        .into_iter()
+        .filter_map(|d| {
+            let file = d.range.file_id;
+            let diagnostic = convert_diagnostic(&line_index, d);
+            if file == file_id {
+                return Some(diagnostic);
+            }
+            if supports_related {
+                related_documents.entry(file).or_insert_with(Vec::new).push(diagnostic);
+            }
+            None
+        });
+    Ok(lsp_types::DocumentDiagnosticReportResult::Report(
+        lsp_types::DocumentDiagnosticReport::Full(lsp_types::RelatedFullDocumentDiagnosticReport {
+            full_document_diagnostic_report: lsp_types::FullDocumentDiagnosticReport {
+                result_id: None,
+                items: diagnostics.collect(),
+            },
+            related_documents: related_documents.is_empty().not().then(|| {
+                related_documents
+                    .into_iter()
+                    .map(|(id, items)| {
+                        (
+                            to_proto::url(&snap, id),
+                            lsp_types::DocumentDiagnosticReportKind::Full(
+                                lsp_types::FullDocumentDiagnosticReport { result_id: None, items },
+                            ),
+                        )
+                    })
+                    .collect()
+            }),
+        }),
+    ))
+}
+
 pub(crate) fn handle_document_symbol(
     snap: GlobalStateSnapshot,
     params: lsp_types::DocumentSymbolParams,

crates/rust-analyzer/src/lsp/capabilities.rs

@@ -155,7 +155,15 @@ pub fn server_capabilities(config: &Config) -> ServerCapabilities {
             "ssr": true,
             "workspaceSymbolScopeKindFiltering": true,
         })),
-        diagnostic_provider: None,
+        diagnostic_provider: Some(lsp_types::DiagnosticServerCapabilities::Options(
+            lsp_types::DiagnosticOptions {
+                identifier: None,
+                inter_file_dependencies: true,
+                // FIXME
+                workspace_diagnostics: false,
+                work_done_progress_options: WorkDoneProgressOptions { work_done_progress: None },
+            },
+        )),
         inline_completion_provider: None,
     }
 }
@@ -380,6 +388,15 @@ impl ClientCapabilities {
         .unwrap_or_default()
     }
 
+    pub fn text_document_diagnostic(&self) -> bool {
+        (|| -> _ { self.0.text_document.as_ref()?.diagnostic.as_ref() })().is_some()
+    }
+
+    pub fn text_document_diagnostic_related_document_support(&self) -> bool {
+        (|| -> _ { self.0.text_document.as_ref()?.diagnostic.as_ref()?.related_document_support })()
+            == Some(true)
+    }
+
     pub fn code_action_group(&self) -> bool {
         self.experimental_bool("codeActionGroup")
     }

crates/rust-analyzer/src/main_loop.rs

@@ -417,6 +417,8 @@ impl GlobalState {
                 }
             }
 
+            let supports_diagnostic_pull_model = self.config.text_document_diagnostic();
+
             let client_refresh = became_quiescent || state_changed;
             if client_refresh {
                 // Refresh semantic tokens if the client supports it.
@@ -434,11 +436,21 @@ impl GlobalState {
                 if self.config.inlay_hints_refresh() {
                     self.send_request::<lsp_types::request::InlayHintRefreshRequest>((), |_, _| ());
                 }
+
+                if supports_diagnostic_pull_model {
+                    self.send_request::<lsp_types::request::WorkspaceDiagnosticRefresh>(
+                        (),
+                        |_, _| (),
+                    );
+                }
             }
 
             let project_or_mem_docs_changed =
                 became_quiescent || state_changed || memdocs_added_or_removed;
-            if project_or_mem_docs_changed && self.config.publish_diagnostics(None) {
+            if project_or_mem_docs_changed
+                && !supports_diagnostic_pull_model
+                && self.config.publish_diagnostics(None)
+            {
                 self.update_diagnostics();
             }
             if project_or_mem_docs_changed && self.config.test_explorer() {
@@ -1080,6 +1092,17 @@ impl GlobalState {
             .on_latency_sensitive::<NO_RETRY, lsp_request::SemanticTokensRangeRequest>(handlers::handle_semantic_tokens_range)
             // FIXME: Some of these NO_RETRY could be retries if the file they are interested didn't change.
             // All other request handlers
+            .on_or::<NO_RETRY, lsp_request::DocumentDiagnosticRequest>(handlers::handle_document_diagnostics, || lsp_types::DocumentDiagnosticReportResult::Report(
+                lsp_types::DocumentDiagnosticReport::Full(
+                    lsp_types::RelatedFullDocumentDiagnosticReport {
+                        related_documents: None,
+                        full_document_diagnostic_report: lsp_types::FullDocumentDiagnosticReport {
+                            result_id: None,
+                            items: vec![],
+                        },
+                    },
+                ),
+            ))
             .on::<RETRY, lsp_request::DocumentSymbolRequest>(handlers::handle_document_symbol)
             .on::<RETRY, lsp_request::FoldingRangeRequest>(handlers::handle_folding_range)
             .on::<NO_RETRY, lsp_request::SignatureHelpRequest>(handlers::handle_signature_help)