fix(resolver): allow builtins to be imported via subpath imports

src/resolver/resolver.zig

@@ -1569,10 +1569,15 @@ pub const Resolver = struct {
 
         // Find the parent directory with the "package.json" file
         var dir_info_package_json: ?*DirInfo = dir_info;
-        while (dir_info_package_json != null and dir_info_package_json.?.package_json == null) : (dir_info_package_json = dir_info_package_json.?.getParent()) {}
+        while (dir_info_package_json != null and dir_info_package_json.?.package_json == null)
+            dir_info_package_json = dir_info_package_json.?.getParent();
 
         // Check for subpath imports: https://nodejs.org/api/packages.html#subpath-imports
-        if (dir_info_package_json != null and strings.hasPrefix(import_path, "#") and !forbid_imports and dir_info_package_json.?.package_json.?.imports != null) {
+        if (dir_info_package_json != null and
+            strings.hasPrefixComptime(import_path, "#") and
+            !forbid_imports and
+            dir_info_package_json.?.package_json.?.imports != null)
+        {
             return r.loadPackageImports(import_path, dir_info_package_json.?, kind, global_cache);
         }
 
@@ -2871,7 +2876,9 @@ pub const Resolver = struct {
 
         const esmodule = ESModule{
             .conditions = switch (kind) {
-                ast.ImportKind.require, ast.ImportKind.require_resolve => r.opts.conditions.require,
+                ast.ImportKind.require,
+                ast.ImportKind.require_resolve,
+                => r.opts.conditions.require,
                 else => r.opts.conditions.import,
             },
             .allocator = r.allocator,
@@ -2881,7 +2888,15 @@ pub const Resolver = struct {
 
         const esm_resolution = esmodule.resolveImports(import_path, imports_map.root);
 
-        if (esm_resolution.status == .PackageResolve)
+        if (esm_resolution.status == .PackageResolve) {
+            if (JSC.HardcodedModule.Aliases.get(esm_resolution.path, .bun)) |builtin| {
+                return .{
+                    .success = .{
+                        .path_pair = .{ .primary = bun.fs.Path.init(builtin.path) },
+                    },
+                };
+            }
+
             return r.loadNodeModules(
                 esm_resolution.path,
                 kind,
@@ -2889,6 +2904,7 @@ pub const Resolver = struct {
                 global_cache,
                 true,
             );
+        }
 
         if (r.handleESMResolution(esm_resolution, package_json.source.path.name.dir, kind, package_json, "")) |result| {
             return .{ .success = result };

test/js/bun/resolve/package.json

@@ -0,0 +1,8 @@
+{
+  "name": "hello",
+  "imports": {
+    "#async_hooks": "async_hooks",
+    "#bun": "bun",
+    "#bun_test": "bun:test"
+  }
+}

test/js/bun/resolve/resolve-test.js

@@ -51,20 +51,20 @@ it("#imports with wildcard", async () => {
 });
 
 it("import.meta.resolve", async () => {
-  expect(await import.meta.resolve("./resolve-test.test.js")).toBe(import.meta.path);
+  expect(await import.meta.resolve("./resolve-test.js")).toBe(import.meta.path);
 
-  expect(await import.meta.resolve("./resolve-test.test.js", import.meta.path)).toBe(import.meta.path);
+  expect(await import.meta.resolve("./resolve-test.js", import.meta.path)).toBe(import.meta.path);
 
   expect(
     // optional second param can be any path, including a dir
-    await import.meta.resolve("./resolve/resolve-test.test.js", join(import.meta.path, "../")),
+    await import.meta.resolve("./resolve/resolve-test.js", join(import.meta.path, "../")),
   ).toBe(import.meta.path);
 
   // can be a package path
   expect((await import.meta.resolve("react", import.meta.path)).length > 0).toBe(true);
 
   // file extensions are optional
-  expect(await import.meta.resolve("./resolve-test.test")).toBe(import.meta.path);
+  expect(await import.meta.resolve("./resolve-test")).toBe(import.meta.path);
 
   // works with tsconfig.json "paths"
   expect(await import.meta.resolve("foo/bar")).toBe(join(import.meta.path, "../baz.js"));
@@ -108,12 +108,12 @@ it("import.meta.resolve", async () => {
 // the slightly lower level API, which doesn't prefill the second param
 // and expects a directory instead of a filepath
 it("Bun.resolve", async () => {
-  expect(await Bun.resolve("./resolve-test.test.js", import.meta.dir)).toBe(import.meta.path);
+  expect(await Bun.resolve("./resolve-test.js", import.meta.dir)).toBe(import.meta.path);
 });
 
 // synchronous
 it("Bun.resolveSync", () => {
-  expect(Bun.resolveSync("./resolve-test.test.js", import.meta.dir)).toBe(import.meta.path);
+  expect(Bun.resolveSync("./resolve-test.js", import.meta.dir)).toBe(import.meta.path);
 });
 
 it("self-referencing imports works", async () => {

test/js/bun/resolve/resolve.test.ts

@@ -7,18 +7,14 @@ it("spawn test file", () => {
   writePackageJSONImportsFixture();
   writePackageJSONExportsFixture();
 
-  copyFileSync(join(import.meta.dir, "resolve-test.js"), join(import.meta.dir, "resolve-test.test.js"));
-
   const { exitCode } = Bun.spawnSync({
-    cmd: [bunExe(), "test", "resolve-test.test.js"],
+    cmd: [bunExe(), "test", "./resolve-test.js"],
     env: bunEnv,
     cwd: import.meta.dir,
+    stdio: ['inherit', 'inherit', 'inherit'],
   });
 
   expect(exitCode).toBe(0);
-
-  rmSync(join(import.meta.dir, "resolve-test.test.js"));
-  expect(existsSync(join(import.meta.dir, "resolve-test.test.js"))).toBe(false);
 });
 
 function writePackageJSONExportsFixture() {
@@ -78,6 +74,8 @@ function writePackageJSONImportsFixture() {
           "#foo": "./foo/private-foo.js",
 
           "#internal-react": "react",
+
+          "#to_node_module": "async_hooks",
         },
       },
       null,
@@ -291,3 +289,18 @@ it("import long string should not segfault", async () => {
     await import.meta.require.resolve("a".repeat(10000));
   } catch {}
 });
+
+it('import override to node builtin', async() => {
+  // @ts-expect-error
+  expect(await import("#async_hooks")).toBeDefined();
+});
+
+it('import override to bun', async() => {
+  // @ts-expect-error
+  expect(await import("#bun")).toBeDefined();
+});
+
+it.todo('import override to bun:test', async() => {
+  // @ts-expect-error
+  expect(await import("#bun_test")).toBeDefined();
+});