refactor(linter/plugins): use fixed-size allocators when ExternalLinter exists

apps/oxlint/src/raw_fs.rs

@@ -14,7 +14,7 @@ use oxc_linter::RuntimeFileSystem;
 /// Identical to `OsFileSystem`, except that `read_to_arena_str` reads the file's contents into
 /// start of the allocator, instead of the end. This conforms to what raw transfer needs.
 ///
-/// Must only be used in conjunction with `AllocatorPool` with `fixed_size` feature enabled,
+/// Must only be used in conjunction with `AllocatorPool` created with `new_fixed_size`,
 /// which wraps `Allocator`s with a custom `Drop` impl, which makes `read_to_arena_str` safe.
 ///
 /// This is a temporary solution. When we replace `bumpalo` with our own allocator, all strings

crates/oxc_linter/Cargo.toml

@@ -17,7 +17,7 @@ description.workspace = true
 default = []
 ruledocs = ["oxc_macros/ruledocs"] # Enables the `ruledocs` feature for conditional compilation
 language_server = ["oxc_data_structures/rope"] # For the Runtime to support needed information for the language server
-oxlint2 = ["dep:oxc_ast_macros", "oxc_ast_visit/serialize", "tokio/rt-multi-thread"]
+oxlint2 = ["dep:oxc_ast_macros", "oxc_allocator/fixed_size", "oxc_ast_visit/serialize", "tokio/rt-multi-thread"]
 disable_oxlint2 = []
 force_test_reporter = []
 

crates/oxc_linter/src/service/runtime.rs

@@ -265,7 +265,21 @@ impl Runtime {
         let _ = rayon::ThreadPoolBuilder::new().build_global();
 
         let thread_count = rayon::current_num_threads();
-        let allocator_pool = AllocatorPool::new(thread_count);
+
+        // If an external linter is used (JS plugins), we must use fixed-size allocators,
+        // for compatibility with raw transfer
+        let allocator_pool = if linter.has_external_linter() {
+            #[cfg(all(feature = "oxlint2", not(feature = "disable_oxlint2")))]
+            {
+                AllocatorPool::new_fixed_size(thread_count)
+            }
+            #[cfg(not(all(feature = "oxlint2", not(feature = "disable_oxlint2"))))]
+            {
+                panic!("`oxlint2` feature must be enabled when using external linters");
+            }
+        } else {
+            AllocatorPool::new(thread_count)
+        };
 
         let resolver = options.cross_module.then(|| {
             Self::get_resolver(options.tsconfig.or_else(|| Some(options.cwd.join("tsconfig.json"))))