fix(pnp): align exports resolution with enhanced-resolve

fixtures/pnp/package.json

@@ -2,6 +2,7 @@
   "name": "pnp",
   "packageManager": "yarn@4.3.1",
   "dependencies": {
+    "@user/m1": "link:./shared-name-mismatch",
     "extend": "3.0.2",
     "is-even": "^1.0.0",
     "is-odd": "^3.0.1",

fixtures/pnp/shared-name-mismatch/dist/a.js

@@ -0,0 +1 @@
+module.exports = "feature";

fixtures/pnp/shared-name-mismatch/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "shared-package",
+  "version": "1.0.0",
+  "exports": {
+    ".": "./dist/a.js",
+    "./x": "./dist/a.js"
+  }
+}

fixtures/pnp/yarn.lock

@@ -5,6 +5,12 @@ __metadata:
   version: 8
   cacheKey: 10c0
 
+"@user/m1@link:./shared-name-mismatch::locator=pnp%40workspace%3A.":
+  version: 0.0.0-use.local
+  resolution: "@user/m1@link:./shared-name-mismatch::locator=pnp%40workspace%3A."
+  languageName: node
+  linkType: soft
+
 "extend@npm:3.0.2":
   version: 3.0.2
   resolution: "extend@npm:3.0.2"
@@ -88,6 +94,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "pnp@workspace:."
   dependencies:
+    "@user/m1": "link:./shared-name-mismatch"
     extend: "npm:3.0.2"
     is-even: "npm:^1.0.0"
     is-odd: "npm:^3.0.1"

src/lib.rs

@@ -1022,21 +1022,26 @@ impl<Fs: FileSystem + Send + Sync> ResolverGeneric<Fs> {
     match resolution {
       Ok(pnp::Resolution::Resolved(path, subpath)) => {
         let cached_path = self.cache.value(&path);
-
-        let export_resolution = self.load_package_self(&cached_path, specifier, ctx).await?;
-        // can be found in pnp cached folder
+        let normalized_subpath = subpath
+          .as_deref()
+          .map(|subpath| subpath.trim_start_matches('/'))
+          .filter(|subpath| !subpath.is_empty());
+
+        // Mirror enhanced-resolve's PnP pipeline by resolving exports from the
+        // request-derived subpath instead of PACKAGE_SELF name matching.
+        let exports_subpath =
+          normalized_subpath.map_or_else(String::new, |subpath| format!("/{subpath}"));
+        let export_resolution = self
+          .load_package_exports(specifier, &exports_subpath, &cached_path, ctx)
+          .await?;
         if export_resolution.is_some() {
           return Ok(export_resolution);
         }
-        let is_bare = subpath.is_none();
-
-        let inner_request = subpath.map_or_else(
-          || ".".to_string(),
-          |mut p| {
-            p.insert_str(0, "./");
-            p
-          },
-        );
+
+        let is_bare = normalized_subpath.is_none();
+
+        let inner_request = normalized_subpath
+          .map_or_else(|| ".".to_string(), |subpath| format!("./{subpath}"));
 
         let mut inner_options = self.options().clone();
         if is_bare {

src/tests/pnp.rs

@@ -303,3 +303,43 @@ async fn resolve_pnp_transitive_dep_from_global_cache() {
     "Expected isarray in global cache, got: {isarray}"
   );
 }
+
+#[tokio::test]
+async fn resolve_pnp_should_handle_exports_field_when_using_pnp() {
+  // Mimics enhanced-resolve: "should handle the exports field when using PnP"
+  let fixture = super::fixture_root().join("pnp");
+
+  let resolver = Resolver::new(ResolveOptions {
+    extensions: vec![".js".into()],
+    condition_names: vec!["import".into()],
+    ..ResolveOptions::default()
+  });
+
+  assert_eq!(
+    resolver
+      .resolve(&fixture, "@user/m1")
+      .await
+      .map(|r| r.full_path()),
+    Ok(fixture.join("shared-name-mismatch/dist/a.js"))
+  );
+}
+
+#[tokio::test]
+async fn resolve_pnp_should_handle_exports_field_when_using_pnp_with_sub_path() {
+  // Mimics enhanced-resolve: "should handle the exports field when using PnP (with sub path)"
+  let fixture = super::fixture_root().join("pnp");
+
+  let resolver = Resolver::new(ResolveOptions {
+    extensions: vec![".js".into()],
+    condition_names: vec!["import".into()],
+    ..ResolveOptions::default()
+  });
+
+  assert_eq!(
+    resolver
+      .resolve(&fixture, "@user/m1/x")
+      .await
+      .map(|r| r.full_path()),
+    Ok(fixture.join("shared-name-mismatch/dist/a.js"))
+  );
+}