fix(core): keep the loader initialization APIs for embedders

Cargo.toml

@@ -22,7 +22,7 @@ default = ["napi"]
 #
 # The embedder writes its own thin `#[napi]` forwarders — for `create_resolve`,
 # `load`, `transform`, `OxcTransformer`, `set_tsconfig_path`,
-# `get_tsconfig_path`, `initialize_loader`, `freeze_tsconfig`,
+# `get_tsconfig_path`, `initialize_loader_js`, `freeze_tsconfig_js`,
 # `set_transform_deps`, `get_transform_deps`,
 # `transforms_dep`, `freeze_transform_deps`, `transform_module_runner`, and for
 # watch mode `enable_watch_report` and `take_watch_dependencies` — compiling this crate against

src/lib.rs

@@ -862,8 +862,7 @@ pub fn initialize_loader(path: Option<String>) -> Result<()> {
     set_tsconfig_override(path, false, "setTsconfigPath()")
 }
 
-#[cfg(feature = "napi")]
-#[napi(js_name = "initializeLoader")]
+#[cfg_attr(feature = "napi", napi(js_name = "initializeLoader"))]
 /// Initialize this loader from a frozen tsconfig selection. A missing or empty path
 /// selects discovery without reading environment variables. The optional source
 /// preserves the original diagnostic label: `setTsconfigPath()`, `TS_NODE_PROJECT`,
@@ -946,8 +945,7 @@ pub fn freeze_tsconfig(cwd: String) -> FrozenTsconfig {
     }
 }
 
-#[cfg(feature = "napi")]
-#[napi(js_name = "freezeTsconfig")]
+#[cfg_attr(feature = "napi", napi(js_name = "freezeTsconfig"))]
 /// Freeze this thread's effective tsconfig path and diagnostic source for an
 /// asynchronous loader. An absent path means discovery. This does not parse the
 /// config or emit diagnostics; it prevents later changes to the selected config.

tests/loader_context.rs

@@ -13,7 +13,8 @@ use std::{
 
 use napi::Either;
 use oxc_node::{
-    CapturedLoaderContext, OxcTransformer, get_tsconfig_path, set_transform_deps, set_tsconfig_path,
+    CapturedLoaderContext, OxcTransformer, get_tsconfig_path, initialize_loader_js,
+    set_transform_deps, set_tsconfig_path,
 };
 
 const SOURCE: &str = r#"
@@ -175,3 +176,25 @@ fn nested_contexts_restore_after_errors_and_panics() {
     });
     assert_eq!(get_tsconfig_path(), None);
 }
+
+#[test]
+fn embedders_initialize_loaders_from_a_frozen_selection() {
+    let fixture = Fixture::new();
+    thread::scope(|scope| {
+        scope
+            .spawn(|| {
+                assert!(
+                    error_reason(initialize_loader_js(None, Some("unknown".into())))
+                        .contains("Invalid tsconfig source")
+                );
+                unwrap_oxc(initialize_loader_js(
+                    Some(fixture.config("assign")),
+                    Some("TS_NODE_PROJECT".into()),
+                ));
+                assert_eq!(get_tsconfig_path(), Some(fixture.config("assign")));
+                assert_eq!(setter_calls(&transform(&fixture.transformer())), 1);
+            })
+            .join()
+            .unwrap();
+    });
+}