Merge #8866

8866: Update salsa r=matklad a=jonas-schievink

This updates salsa to include salsa-rs/salsa#265, and removes all cancellation-related code from rust-analyzer

Co-authored-by: Jonas Schievink <jonasschievink@gmail.com>

Author: bors[bot]

Cargo.lock

@@ -10,7 +10,7 @@ edition = "2018"
 doctest = false
 
 [dependencies]
-salsa = "0.16.0"
+salsa = "0.17.0-pre.1"
 rustc-hash = "1.1.0"
 
 syntax = { path = "../syntax", version = "0.0.0" }

crates/base_db/Cargo.toml

@@ -1,5 +1,4 @@
 //! base_db defines basic database traits. The concrete DB is defined by ide.
-mod cancellation;
 mod input;
 mod change;
 pub mod fixture;
@@ -10,14 +9,13 @@ use rustc_hash::FxHashSet;
 use syntax::{ast, Parse, SourceFile, TextRange, TextSize};
 
 pub use crate::{
-    cancellation::Canceled,
     change::Change,
     input::{
         CrateData, CrateDisplayName, CrateGraph, CrateId, CrateName, Dependency, Edition, Env,
         ProcMacro, ProcMacroExpander, ProcMacroId, ProcMacroKind, SourceRoot, SourceRootId,
     },
 };
-pub use salsa;
+pub use salsa::{self, Cancelled};
 pub use vfs::{file_set::FileSet, AnchoredPath, AnchoredPathBuf, FileId, VfsPath};
 
 #[macro_export]
@@ -38,45 +36,6 @@ pub trait Upcast<T: ?Sized> {
     fn upcast(&self) -> &T;
 }
 
-pub trait CheckCanceled {
-    /// Aborts current query if there are pending changes.
-    ///
-    /// rust-analyzer needs to be able to answer semantic questions about the
-    /// code while the code is being modified. A common problem is that a
-    /// long-running query is being calculated when a new change arrives.
-    ///
-    /// We can't just apply the change immediately: this will cause the pending
-    /// query to see inconsistent state (it will observe an absence of
-    /// repeatable read). So what we do is we **cancel** all pending queries
-    /// before applying the change.
-    ///
-    /// We implement cancellation by panicking with a special value and catching
-    /// it on the API boundary. Salsa explicitly supports this use-case.
-    fn check_canceled(&self);
-
-    fn catch_canceled<F, T>(&self, f: F) -> Result<T, Canceled>
-    where
-        Self: Sized + panic::RefUnwindSafe,
-        F: FnOnce(&Self) -> T + panic::UnwindSafe,
-    {
-        // Uncomment to debug missing cancellations.
-        // let _span = profile::heartbeat_span();
-        panic::catch_unwind(|| f(self)).map_err(|err| match err.downcast::<Canceled>() {
-            Ok(canceled) => *canceled,
-            Err(payload) => panic::resume_unwind(payload),
-        })
-    }
-}
-
-impl<T: salsa::Database> CheckCanceled for T {
-    fn check_canceled(&self) {
-        // profile::heartbeat();
-        if self.salsa_runtime().is_current_revision_canceled() {
-            Canceled::throw()
-        }
-    }
-}
-
 #[derive(Clone, Copy, Debug)]
 pub struct FilePosition {
     pub file_id: FileId,
@@ -101,7 +60,7 @@ pub trait FileLoader {
 /// Database which stores all significant input facts: source code and project
 /// model. Everything else in rust-analyzer is derived from these queries.
 #[salsa::query_group(SourceDatabaseStorage)]
-pub trait SourceDatabase: CheckCanceled + FileLoader + std::fmt::Debug {
+pub trait SourceDatabase: FileLoader + std::fmt::Debug {
     // Parses the file into the syntax tree.
     #[salsa::invoke(parse_query)]
     fn parse(&self, file_id: FileId) -> Parse<ast::SourceFile>;

crates/base_db/src/cancellation.rs

@@ -361,7 +361,7 @@ impl<'db> SemanticsImpl<'db> {
         let sa = self.analyze(&parent);
 
         let token = successors(Some(InFile::new(sa.file_id, token)), |token| {
-            self.db.check_canceled();
+            self.db.unwind_if_cancelled();
             let macro_call = token.value.ancestors().find_map(ast::MacroCall::cast)?;
             let tt = macro_call.token_tree()?;
             if !tt.syntax().text_range().contains_range(token.value.text_range()) {

crates/base_db/src/lib.rs

@@ -351,7 +351,7 @@ impl DefCollector<'_> {
         let mut i = 0;
         'outer: loop {
             loop {
-                self.db.check_canceled();
+                self.db.unwind_if_cancelled();
                 loop {
                     if self.resolve_imports() == ReachedFixedPoint::Yes {
                         break;
@@ -836,7 +836,7 @@ impl DefCollector<'_> {
         vis: Visibility,
         import_type: ImportType,
     ) {
-        self.db.check_canceled();
+        self.db.unwind_if_cancelled();
         self.update_recursive(module_id, resolutions, vis, import_type, 0)
     }
 

crates/hir/src/semantics.rs

@@ -119,7 +119,7 @@ impl<'a> InferenceContext<'a> {
     }
 
     fn infer_expr_inner(&mut self, tgt_expr: ExprId, expected: &Expectation) -> Ty {
-        self.db.check_canceled();
+        self.db.unwind_if_cancelled();
 
         let body = Arc::clone(&self.body); // avoid borrow checker problem
         let ty = match &body[tgt_expr] {

crates/hir_def/src/nameres/collector.rs

@@ -112,7 +112,7 @@ fn solve(
     let fuel = std::cell::Cell::new(CHALK_SOLVER_FUEL);
 
     let should_continue = || {
-        context.db.check_canceled();
+        db.unwind_if_cancelled();
         let remaining = fuel.get();
         fuel.set(remaining - 1);
         if remaining == 0 {