clear source texts

crates/ruff_benchmark/benches/ty.rs

@@ -141,7 +141,7 @@ fn benchmark_incremental(criterion: &mut Criterion) {
                 &case.file_path,
                 format!(
                     "{}\n# A comment\n",
-                    source_text(&case.db, case.file).as_str()
+                    source_text(&case.db, case.file).load().as_str()
                 ),
             )
             .unwrap();

crates/ruff_db/src/diagnostic/render.rs

@@ -8,10 +8,11 @@ use ruff_source_file::{LineIndex, OneIndexed, SourceCode};
 use ruff_text_size::{TextRange, TextSize};
 
 use crate::diagnostic::stylesheet::{DiagnosticStylesheet, fmt_styled};
+use crate::source::SourceTextRef;
 use crate::{
     Db,
     files::File,
-    source::{SourceText, line_index, source_text},
+    source::{line_index, source_text},
     system::SystemPath,
 };
 
@@ -644,7 +645,7 @@ impl FileResolver for &dyn Db {
 
     fn input(&self, file: File) -> Input {
         Input {
-            text: source_text(*self, file),
+            text: source_text(*self, file).load(),
             line_index: line_index(*self, file),
         }
     }
@@ -657,7 +658,7 @@ impl FileResolver for &dyn Db {
 /// line index for efficiently querying its contents.
 #[derive(Clone, Debug)]
 pub struct Input {
-    pub(crate) text: SourceText,
+    pub(crate) text: SourceTextRef,
     pub(crate) line_index: LineIndex,
 }
 
@@ -2158,7 +2159,7 @@ watermelon
             let span = self.path(path);
 
             let file = span.expect_ty_file();
-            let text = source_text(&self.db, file);
+            let text = source_text(&self.db, file).load();
             let line_index = line_index(&self.db, file);
             let source = SourceCode::new(text.as_str(), &line_index);
 

crates/ruff_db/src/parsed.rs

@@ -30,7 +30,7 @@ pub fn parsed_module(db: &dyn Db, file: File) -> ParsedModule {
 }
 
 pub fn parsed_module_impl(db: &dyn Db, file: File) -> Parsed<ModModule> {
-    let source = source_text(db, file);
+    let source = source_text(db, file).load();
     let ty = file.source_type(db);
 
     let target_version = db.python_version();

crates/ruff_db/src/source.rs

@@ -1,6 +1,7 @@
 use std::ops::Deref;
 use std::sync::Arc;
 
+use arc_swap::ArcSwapOption;
 use countme::Count;
 
 use ruff_notebook::Notebook;
@@ -11,7 +12,7 @@ use crate::Db;
 use crate::files::{File, FilePath};
 
 /// Reads the source text of a python text file (must be valid UTF8) or notebook.
-#[salsa::tracked]
+#[salsa::tracked(no_eq)]
 pub fn source_text(db: &dyn Db, file: File) -> SourceText {
     let path = file.path(db);
     let _span = tracing::trace_span!("source_text", file = %path).entered();
@@ -38,11 +39,11 @@ pub fn source_text(db: &dyn Db, file: File) -> SourceText {
     };
 
     SourceText {
-        inner: Arc::new(SourceTextInner {
+        inner: Arc::new(ArcSwapOption::new(Some(Arc::new(SourceTextInner {
             kind,
             read_error,
-            count: Count::new(),
-        }),
+            _count: Count::new(),
+        })))),
     }
 }
 
@@ -65,12 +66,37 @@ fn is_notebook(path: &FilePath) -> bool {
 /// The file containing the source text can either be a text file or a notebook.
 ///
 /// Cheap cloneable in `O(1)`.
-#[derive(Clone, Eq, PartialEq)]
+#[derive(Clone)]
 pub struct SourceText {
+    inner: Arc<ArcSwapOption<SourceTextInner>>,
+}
+
+impl PartialEq for SourceText {
+    fn eq(&self, other: &Self) -> bool {
+        Arc::ptr_eq(&self.inner, &other.inner)
+    }
+}
+
+impl Eq for SourceText {}
+
+impl SourceText {
+    pub fn load(&self) -> SourceTextRef {
+        SourceTextRef {
+            inner: self.inner.load_full().unwrap(),
+        }
+    }
+
+    pub fn clear(&self) {
+        self.inner.store(None);
+    }
+}
+
+#[derive(Clone, PartialEq, Eq)]
+pub struct SourceTextRef {
     inner: Arc<SourceTextInner>,
 }
 
-impl SourceText {
+impl SourceTextRef {
     /// Returns the python code as a `str`.
     pub fn as_str(&self) -> &str {
         match &self.inner.kind {
@@ -98,7 +124,7 @@ impl SourceText {
     }
 }
 
-impl Deref for SourceText {
+impl Deref for SourceTextRef {
     type Target = str;
 
     fn deref(&self) -> &str {
@@ -106,7 +132,7 @@ impl Deref for SourceText {
     }
 }
 
-impl std::fmt::Debug for SourceText {
+impl std::fmt::Debug for SourceTextRef {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let mut dbg = f.debug_tuple("SourceText");
 
@@ -123,11 +149,18 @@ impl std::fmt::Debug for SourceText {
     }
 }
 
-#[derive(Eq, PartialEq)]
 struct SourceTextInner {
-    count: Count<SourceText>,
     kind: SourceTextKind,
     read_error: Option<SourceTextError>,
+    _count: Count<SourceText>,
+}
+
+impl Eq for SourceTextInner {}
+
+impl PartialEq for SourceTextInner {
+    fn eq(&self, other: &Self) -> bool {
+        self.kind.eq(&other.kind) && self.read_error.eq(&other.read_error)
+    }
 }
 
 #[derive(Eq, PartialEq)]
@@ -161,7 +194,7 @@ pub enum SourceTextError {
 pub fn line_index(db: &dyn Db, file: File) -> LineIndex {
     let _span = tracing::trace_span!("line_index", ?file).entered();
 
-    let source = source_text(db, file);
+    let source = source_text(db, file).load();
 
     LineIndex::from_source_text(&source)
 }
@@ -188,11 +221,11 @@ mod tests {
 
         let file = system_path_to_file(&db, path).unwrap();
 
-        assert_eq!(source_text(&db, file).as_str(), "x = 10");
+        assert_eq!(source_text(&db, file).load().as_str(), "x = 10");
 
         db.write_file(path, "x = 20").unwrap();
 
-        assert_eq!(source_text(&db, file).as_str(), "x = 20");
+        assert_eq!(source_text(&db, file).load().as_str(), "x = 20");
 
         Ok(())
     }
@@ -206,13 +239,13 @@ mod tests {
 
         let file = system_path_to_file(&db, path).unwrap();
 
-        assert_eq!(source_text(&db, file).as_str(), "x = 10");
+        assert_eq!(source_text(&db, file).load().as_str(), "x = 10");
 
         // Change the file permission only
         file.set_permissions(&mut db).to(Some(0o777));
 
         db.clear_salsa_events();
-        assert_eq!(source_text(&db, file).as_str(), "x = 10");
+        assert_eq!(source_text(&db, file).load().as_str(), "x = 10");
 
         let events = db.take_salsa_events();
 
@@ -234,7 +267,7 @@ mod tests {
 
         let file = system_path_to_file(&db, path).unwrap();
         let index = line_index(&db, file);
-        let source = source_text(&db, file);
+        let source = source_text(&db, file).load();
 
         assert_eq!(index.line_count(), 2);
         assert_eq!(
@@ -276,7 +309,7 @@ mod tests {
         )?;
 
         let file = system_path_to_file(&db, path).unwrap();
-        let source = source_text(&db, file);
+        let source = source_text(&db, file).load();
 
         assert!(source.is_notebook());
         assert_eq!(source.as_str(), "x = 10\n");

crates/ruff_linter/src/checkers/ast/mod.rs

@@ -21,6 +21,7 @@
 //! represents the lint-rule analysis phase. In the future, these steps may be separated into
 //! distinct passes over the AST.
 
+use std::borrow::Cow;
 use std::cell::RefCell;
 use std::path::Path;
 
@@ -667,8 +668,8 @@ impl SemanticSyntaxContext for Checker<'_> {
         }
     }
 
-    fn source(&self) -> &str {
-        self.source()
+    fn source(&self) -> Cow<'_, str> {
+        Cow::Borrowed(self.source())
     }
 
     fn future_annotations_or_stub(&self) -> bool {

crates/ruff_python_formatter/src/lib.rs

@@ -172,7 +172,7 @@ pub fn formatted_file(db: &dyn Db, file: File) -> Result<Option<String>, FormatM
     }
 
     let comment_ranges = CommentRanges::from(parsed.tokens());
-    let source = source_text(db.upcast(), file);
+    let source = source_text(db.upcast(), file).load();
 
     let formatted = format_node(&parsed, &comment_ranges, &source, options)?;
     let printed = formatted.print()?;

crates/ruff_python_parser/src/semantic_errors.rs

@@ -3,6 +3,7 @@
 //! This checker is not responsible for traversing the AST itself. Instead, its
 //! [`SemanticSyntaxChecker::visit_stmt`] and [`SemanticSyntaxChecker::visit_expr`] methods should
 //! be called in a parent `Visitor`'s `visit_stmt` and `visit_expr` methods, respectively.
+use std::borrow::Cow;
 use std::fmt::Display;
 
 use ruff_python_ast::{
@@ -1698,7 +1699,7 @@ pub trait SemanticSyntaxContext {
     fn python_version(&self) -> PythonVersion;
 
     /// Returns the source text under analysis.
-    fn source(&self) -> &str;
+    fn source(&self) -> Cow<'_, str>;
 
     /// Return the [`TextRange`] at which a name is declared as `global` in the current scope.
     fn global(&self, name: &str) -> Option<TextRange>;

crates/ruff_python_parser/tests/fixtures.rs

@@ -1,3 +1,4 @@
+use std::borrow::Cow;
 use std::cell::RefCell;
 use std::cmp::Ordering;
 use std::fmt::{Formatter, Write};
@@ -519,8 +520,8 @@ impl SemanticSyntaxContext for SemanticSyntaxCheckerVisitor<'_> {
         self.diagnostics.borrow_mut().push(error);
     }
 
-    fn source(&self) -> &str {
-        self.source
+    fn source(&self) -> Cow<'_, str> {
+        Cow::Borrowed(self.source)
     }
 
     fn global(&self, _name: &str) -> Option<TextRange> {

crates/ty/tests/file_watching.rs

@@ -643,7 +643,7 @@ fn changed_file() -> anyhow::Result<()> {
     let foo_path = case.project_path("foo.py");
 
     let foo = case.system_file(&foo_path)?;
-    assert_eq!(source_text(case.db(), foo).as_str(), foo_source);
+    assert_eq!(source_text(case.db(), foo).load().as_str(), foo_source);
     case.assert_indexed_project_files([foo]);
 
     update_file(&foo_path, "print('Version 2')")?;
@@ -654,7 +654,10 @@ fn changed_file() -> anyhow::Result<()> {
 
     case.apply_changes(changes, None);
 
-    assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 2')");
+    assert_eq!(
+        source_text(case.db(), foo).load().as_str(),
+        "print('Version 2')"
+    );
     case.assert_indexed_project_files([foo]);
 
     Ok(())
@@ -1262,8 +1265,14 @@ fn hard_links_in_project() -> anyhow::Result<()> {
     let bar_path = case.project_path("bar.py");
     let bar = case.system_file(&bar_path).unwrap();
 
-    assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 1')");
-    assert_eq!(source_text(case.db(), bar).as_str(), "print('Version 1')");
+    assert_eq!(
+        source_text(case.db(), foo).load().as_str(),
+        "print('Version 1')"
+    );
+    assert_eq!(
+        source_text(case.db(), bar).load().as_str(),
+        "print('Version 1')"
+    );
     case.assert_indexed_project_files([bar, foo]);
 
     // Write to the hard link target.
@@ -1273,11 +1282,17 @@ fn hard_links_in_project() -> anyhow::Result<()> {
 
     case.apply_changes(changes, None);
 
-    assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 2')");
+    assert_eq!(
+        source_text(case.db(), foo).load().as_str(),
+        "print('Version 2')"
+    );
 
     // macOS is the only platform that emits events for every hardlink.
     if cfg!(target_os = "macos") {
-        assert_eq!(source_text(case.db(), bar).as_str(), "print('Version 2')");
+        assert_eq!(
+            source_text(case.db(), bar).load().as_str(),
+            "print('Version 2')"
+        );
     }
 
     Ok(())
@@ -1334,8 +1349,14 @@ fn hard_links_to_target_outside_project() -> anyhow::Result<()> {
     let bar_path = case.project_path("bar.py");
     let bar = case.system_file(&bar_path).unwrap();
 
-    assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 1')");
-    assert_eq!(source_text(case.db(), bar).as_str(), "print('Version 1')");
+    assert_eq!(
+        source_text(case.db(), foo).load().as_str(),
+        "print('Version 1')"
+    );
+    assert_eq!(
+        source_text(case.db(), bar).load().as_str(),
+        "print('Version 1')"
+    );
 
     // Write to the hard link target.
     update_file(foo_path, "print('Version 2')").context("Failed to update foo.py")?;
@@ -1344,7 +1365,10 @@ fn hard_links_to_target_outside_project() -> anyhow::Result<()> {
 
     case.apply_changes(changes, None);
 
-    assert_eq!(source_text(case.db(), bar).as_str(), "print('Version 2')");
+    assert_eq!(
+        source_text(case.db(), bar).load().as_str(),
+        "print('Version 2')"
+    );
 
     Ok(())
 }
@@ -1450,7 +1474,10 @@ mod unix {
         let baz_project = case.project_path("bar/baz.py");
         let baz_file = baz.file().unwrap();
 
-        assert_eq!(source_text(case.db(), baz_file).as_str(), "def baz(): ...");
+        assert_eq!(
+            source_text(case.db(), baz_file).load().as_str(),
+            "def baz(): ..."
+        );
         assert_eq!(
             baz_file.path(case.db()).as_system_path(),
             Some(&*baz_project)
@@ -1467,7 +1494,7 @@ mod unix {
         case.apply_changes(changes, None);
 
         assert_eq!(
-            source_text(case.db(), baz_file).as_str(),
+            source_text(case.db(), baz_file).load().as_str(),
             "def baz(): print('Version 2')"
         );
 
@@ -1480,7 +1507,7 @@ mod unix {
         case.apply_changes(changes, None);
 
         assert_eq!(
-            source_text(case.db(), baz_file).as_str(),
+            source_text(case.db(), baz_file).load().as_str(),
             "def baz(): print('Version 3')"
         );
 
@@ -1533,11 +1560,14 @@ mod unix {
         let patched_bar_baz_file = case.system_file(&patched_bar_baz).unwrap();
 
         assert_eq!(
-            source_text(case.db(), patched_bar_baz_file).as_str(),
+            source_text(case.db(), patched_bar_baz_file).load().as_str(),
             "def baz(): ..."
         );
 
-        assert_eq!(source_text(case.db(), baz_file).as_str(), "def baz(): ...");
+        assert_eq!(
+            source_text(case.db(), baz_file).load().as_str(),
+            "def baz(): ..."
+        );
         assert_eq!(baz_file.path(case.db()).as_system_path(), Some(&*bar_baz));
 
         case.assert_indexed_project_files([patched_bar_baz_file]);
@@ -1564,10 +1594,10 @@ mod unix {
         //
         // That's why I think it's fine to not support this case for now.
 
-        let patched_baz_text = source_text(case.db(), patched_bar_baz_file);
+        let patched_baz_text = source_text(case.db(), patched_bar_baz_file).load();
         let did_update_patched_baz = patched_baz_text.as_str() == "def baz(): print('Version 2')";
 
-        let bar_baz_text = source_text(case.db(), baz_file);
+        let bar_baz_text = source_text(case.db(), baz_file).load();
         let did_update_bar_baz = bar_baz_text.as_str() == "def baz(): print('Version 2')";
 
         assert!(
@@ -1641,12 +1671,12 @@ mod unix {
         let baz_original_file = case.system_file(&baz_original).unwrap();
 
         assert_eq!(
-            source_text(case.db(), baz_original_file).as_str(),
+            source_text(case.db(), baz_original_file).load().as_str(),
             "def baz(): ..."
         );
 
         assert_eq!(
-            source_text(case.db(), baz_site_packages).as_str(),
+            source_text(case.db(), baz_site_packages).load().as_str(),
             "def baz(): ..."
         );
         assert_eq!(
@@ -1665,7 +1695,7 @@ mod unix {
         case.apply_changes(changes, None);
 
         assert_eq!(
-            source_text(case.db(), baz_original_file).as_str(),
+            source_text(case.db(), baz_original_file).load().as_str(),
             "def baz(): print('Version 2')"
         );
 
@@ -1677,7 +1707,7 @@ mod unix {
         // it doesn't seem worth doing considering that as prominent tools like PyCharm don't support it.
         // Pyright does support it, thanks to chokidar.
         assert_ne!(
-            source_text(case.db(), baz_site_packages).as_str(),
+            source_text(case.db(), baz_site_packages).load().as_str(),
             "def baz(): print('Version 2')"
         );
 

crates/ty_ide/src/inlay_hints.rs

@@ -216,7 +216,7 @@ mod tests {
         fn inlay_hints(&self) -> String {
             let hints = inlay_hints(&self.db, self.file, self.range);
 
-            let mut buf = source_text(&self.db, self.file).as_str().to_string();
+            let mut buf = source_text(&self.db, self.file).load().as_str().to_string();
 
             let mut offset = 0;
 

crates/ty_project/src/lib.rs

@@ -479,7 +479,7 @@ impl Project {
         // Abort checking if there are IO errors.
         let source = source_text(db.upcast(), file);
 
-        if let Some(read_error) = source.read_error() {
+        if let Some(read_error) = source.load().read_error() {
             diagnostics.push(
                 IOErrorDiagnostic {
                     file: Some(file),
@@ -525,6 +525,8 @@ impl Project {
             .open_fileset(db)
             .is_none_or(|files| !files.contains(&file))
         {
+            source.clear();
+
             // Drop the AST now that we are done checking this file. It is not currently open,
             // so it is unlikely to be accessed again soon. If any queries need to access the AST
             // from across files, it will be re-parsed.
@@ -747,7 +749,7 @@ mod tests {
         db.memory_file_system().remove_file(path)?;
         file.sync(&mut db);
 
-        assert_eq!(source_text(&db, file).as_str(), "");
+        assert_eq!(source_text(&db, file).load().as_str(), "");
         assert_eq!(
             db.project()
                 .check_file_impl(&db, file)
@@ -764,7 +766,7 @@ mod tests {
         // content returned by `source_text` remains unchanged, but the diagnostics should get updated.
         db.write_file(path, "").unwrap();
 
-        assert_eq!(source_text(&db, file).as_str(), "");
+        assert_eq!(source_text(&db, file).load().as_str(), "");
         assert_eq!(
             db.project()
                 .check_file_impl(&db, file)

crates/ty_python_semantic/src/semantic_index/builder.rs

@@ -1,3 +1,4 @@
+use std::borrow::Cow;
 use std::cell::{OnceCell, RefCell};
 use std::sync::Arc;
 
@@ -2274,8 +2275,9 @@ impl SemanticSyntaxContext for SemanticIndexBuilder<'_, '_> {
         self.python_version
     }
 
-    fn source(&self) -> &str {
-        self.source_text().as_str()
+    fn source(&self) -> Cow<'_, str> {
+        let source_text = self.source_text().load();
+        Cow::Owned(source_text.as_str().to_string())
     }
 
     // We handle the one syntax error that relies on this method (`LoadBeforeGlobalDeclaration`)
@@ -2364,7 +2366,7 @@ impl SemanticSyntaxContext for SemanticIndexBuilder<'_, '_> {
     }
 
     fn in_notebook(&self) -> bool {
-        self.source_text().is_notebook()
+        self.source_text().load().is_notebook()
     }
 
     fn report_semantic_error(&self, error: SemanticSyntaxError) {

crates/ty_python_semantic/src/suppression.rs

@@ -89,7 +89,7 @@ declare_lint! {
 #[salsa::tracked(returns(ref))]
 pub(crate) fn suppressions(db: &dyn Db, file: File) -> Suppressions {
     let parsed = parsed_module(db.upcast(), file).load(db.upcast());
-    let source = source_text(db.upcast(), file);
+    let source = source_text(db.upcast(), file).load();
 
     let mut builder = SuppressionsBuilder::new(&source, db.lint_registry());
     let mut line_start = TextSize::default();

crates/ty_python_semantic/src/types/definition.rs

@@ -32,7 +32,7 @@ impl TypeDefinition<'_> {
         match self {
             Self::Module(module) => {
                 let file = module.file()?;
-                let source = source_text(db.upcast(), file);
+                let source = source_text(db.upcast(), file).load();
                 Some(FileRange::new(file, TextRange::up_to(source.text_len())))
             }
             Self::Class(definition)

crates/ty_python_semantic/src/types/string_annotation.rs

@@ -137,7 +137,7 @@ pub(crate) fn parse_string_annotation(
     let _span = tracing::trace_span!("parse_string_annotation", string=?string_expr.range(), ?file)
         .entered();
 
-    let source = source_text(db.upcast(), file);
+    let source = source_text(db.upcast(), file).load();
 
     if let Some(string_literal) = string_expr.as_single_part_string() {
         let prefix = string_literal.flags.prefix();

crates/ty_server/src/document/location.rs

@@ -31,14 +31,14 @@ impl ToLink for NavigationTarget {
     ) -> Option<lsp_types::LocationLink> {
         let file = self.file();
         let uri = file_to_url(db.upcast(), file)?;
-        let source = source_text(db.upcast(), file);
+        let source = source_text(db.upcast(), file).load();
         let index = line_index(db.upcast(), file);
 
         let target_range = self.full_range().to_lsp_range(&source, &index, encoding);
         let selection_range = self.focus_range().to_lsp_range(&source, &index, encoding);
 
         let src = src.map(|src| {
-            let source = source_text(db.upcast(), src.file());
+            let source = source_text(db.upcast(), src.file()).load();
             let index = line_index(db.upcast(), src.file());
 
             src.range().to_lsp_range(&source, &index, encoding)

crates/ty_server/src/document/range.rs

@@ -163,7 +163,7 @@ impl FileRangeExt for FileRange {
     fn to_location(&self, db: &dyn Db, encoding: PositionEncoding) -> Option<Location> {
         let file = self.file();
         let uri = file_to_url(db, file)?;
-        let source = source_text(db.upcast(), file);
+        let source = source_text(db.upcast(), file).load();
         let line_index = line_index(db.upcast(), file);
 
         let range = self.range().to_lsp_range(&source, &line_index, encoding);

crates/ty_server/src/server/api/diagnostics.rs

@@ -180,7 +180,7 @@ fn to_lsp_diagnostic(
     let range = if let Some(span) = diagnostic.primary_span() {
         let file = span.expect_ty_file();
         let index = line_index(db.upcast(), file);
-        let source = source_text(db.upcast(), file);
+        let source = source_text(db.upcast(), file).load();
 
         span.range()
             .map(|range| range.to_lsp_range(&source, &index, encoding))

crates/ty_server/src/server/api/requests/completion.rs

@@ -39,7 +39,7 @@ impl BackgroundDocumentRequestHandler for CompletionRequestHandler {
             return Ok(None);
         };
 
-        let source = source_text(db, file);
+        let source = source_text(db, file).load();
         let line_index = line_index(db, file);
         let offset = params.text_document_position.position.to_text_size(
             &source,

crates/ty_server/src/server/api/requests/goto_type_definition.rs

@@ -37,7 +37,7 @@ impl BackgroundDocumentRequestHandler for GotoTypeDefinitionRequestHandler {
             return Ok(None);
         };
 
-        let source = source_text(db, file);
+        let source = source_text(db, file).load();
         let line_index = line_index(db, file);
         let offset = params.text_document_position_params.position.to_text_size(
             &source,

crates/ty_server/src/server/api/requests/hover.rs

@@ -37,7 +37,7 @@ impl BackgroundDocumentRequestHandler for HoverRequestHandler {
             return Ok(None);
         };
 
-        let source = source_text(db, file);
+        let source = source_text(db, file).load();
         let line_index = line_index(db, file);
         let offset = params.text_document_position_params.position.to_text_size(
             &source,

crates/ty_server/src/server/api/requests/inlay_hints.rs

@@ -37,7 +37,7 @@ impl BackgroundDocumentRequestHandler for InlayHintRequestHandler {
         };
 
         let index = line_index(db, file);
-        let source = source_text(db, file);
+        let source = source_text(db, file).load();
 
         let range = params
             .range

crates/ty_test/src/assertion.rs

@@ -37,7 +37,7 @@
 use crate::db::Db;
 use ruff_db::files::File;
 use ruff_db::parsed::parsed_module;
-use ruff_db::source::{SourceText, line_index, source_text};
+use ruff_db::source::{SourceTextRef, line_index, source_text};
 use ruff_python_trivia::{CommentRanges, Cursor};
 use ruff_source_file::{LineIndex, OneIndexed};
 use ruff_text_size::{Ranged, TextRange, TextSize};
@@ -49,13 +49,13 @@ use std::str::FromStr;
 #[derive(Debug)]
 pub(crate) struct InlineFileAssertions {
     comment_ranges: CommentRanges,
-    source: SourceText,
+    source: SourceTextRef,
     lines: LineIndex,
 }
 
 impl InlineFileAssertions {
     pub(crate) fn from_file(db: &Db, file: File) -> Self {
-        let source = source_text(db, file);
+        let source = source_text(db, file).load();
         let lines = line_index(db, file);
         let parsed = parsed_module(db, file).load(db);
         let comment_ranges = CommentRanges::from(parsed.tokens());

crates/ty_test/src/matcher.rs

@@ -6,7 +6,7 @@ use crate::diagnostic::SortedDiagnostics;
 use colored::Colorize;
 use ruff_db::diagnostic::{Diagnostic, DiagnosticId};
 use ruff_db::files::File;
-use ruff_db::source::{SourceText, line_index, source_text};
+use ruff_db::source::{SourceTextRef, line_index, source_text};
 use ruff_source_file::{LineIndex, OneIndexed};
 use std::cmp::Ordering;
 use std::ops::Range;
@@ -204,14 +204,14 @@ fn discard_todo_metadata(ty: &str) -> std::borrow::Cow<'_, str> {
 
 struct Matcher {
     line_index: LineIndex,
-    source: SourceText,
+    source: SourceTextRef,
 }
 
 impl Matcher {
     fn from_file(db: &Db, file: File) -> Self {
         Self {
             line_index: line_index(db, file),
-            source: source_text(db, file),
+            source: source_text(db, file).load(),
         }
     }
 

crates/ty_wasm/src/lib.rs

@@ -219,7 +219,7 @@ impl Workspace {
 
     #[wasm_bindgen(js_name = "sourceText")]
     pub fn source_text(&self, file_id: &FileHandle) -> Result<String, Error> {
-        let source_text = ruff_db::source::source_text(&self.db, file_id.file);
+        let source_text = ruff_db::source::source_text(&self.db, file_id.file).load();
 
         Ok(source_text.to_string())
     }
@@ -230,7 +230,7 @@ impl Workspace {
         file_id: &FileHandle,
         position: Position,
     ) -> Result<Vec<LocationLink>, Error> {
-        let source = source_text(&self.db, file_id.file);
+        let source = source_text(&self.db, file_id.file).load();
         let index = line_index(&self.db, file_id.file);
 
         let offset = position.to_text_size(&source, &index, self.position_encoding)?;
@@ -269,7 +269,7 @@ impl Workspace {
 
     #[wasm_bindgen]
     pub fn hover(&self, file_id: &FileHandle, position: Position) -> Result<Option<Hover>, Error> {
-        let source = source_text(&self.db, file_id.file);
+        let source = source_text(&self.db, file_id.file).load();
         let index = line_index(&self.db, file_id.file);
 
         let offset = position.to_text_size(&source, &index, self.position_encoding)?;
@@ -299,7 +299,7 @@ impl Workspace {
         file_id: &FileHandle,
         position: Position,
     ) -> Result<Vec<Completion>, Error> {
-        let source = source_text(&self.db, file_id.file);
+        let source = source_text(&self.db, file_id.file).load();
         let index = line_index(&self.db, file_id.file);
 
         let offset = position.to_text_size(&source, &index, self.position_encoding)?;
@@ -317,7 +317,7 @@ impl Workspace {
     #[wasm_bindgen(js_name = "inlayHints")]
     pub fn inlay_hints(&self, file_id: &FileHandle, range: Range) -> Result<Vec<InlayHint>, Error> {
         let index = line_index(&self.db, file_id.file);
-        let source = source_text(&self.db, file_id.file);
+        let source = source_text(&self.db, file_id.file).load();
 
         let result = inlay_hints(
             &self.db,
@@ -440,7 +440,7 @@ impl Range {
         position_encoding: PositionEncoding,
     ) -> Self {
         let index = line_index(db.upcast(), file_range.file());
-        let source = source_text(db.upcast(), file_range.file());
+        let source = source_text(db.upcast(), file_range.file()).load();
 
         Self::from_text_range(file_range.range(), &index, &source, position_encoding)
     }