From 515fe51d8c4ed5f7c63e9edfb91fa1df1fb5fa7e Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Sun, 16 Aug 2026 22:52:46 -0700
Subject: [PATCH] perf(test): reuse setup registry module (#125087)

---
 src/plugins/setup-registry.test.ts | 37 +++++++++++++-----------------
 1 file changed, 16 insertions(+), 21 deletions(-)

diff --git a/src/plugins/setup-registry.test.ts b/src/plugins/setup-registry.test.ts
index ebc0b3f21884..5131fdb93977 100644
--- a/src/plugins/setup-registry.test.ts
+++ b/src/plugins/setup-registry.test.ts
@@ -33,9 +33,7 @@ let resolvePluginSetupRegistry: typeof import("./setup-registry.js").resolvePlug
 let resolvePluginSetupProviderCore: typeof import("./setup-registry.js").resolvePluginSetupProviderCore;
 let resolvePluginSetupCliBackend: typeof import("./setup-registry.js").resolvePluginSetupCliBackend;
 let runPluginSetupConfigMigrations: typeof import("./setup-registry.js").runPluginSetupConfigMigrations;
-let setPluginSetupRegistryModuleLoaderFactoryForTest:
-  | typeof import("./setup-registry.test-fixtures.js").setPluginSetupRegistryModuleLoaderFactoryForTest
-  | undefined;
+let setPluginSetupRegistryModuleLoaderFactoryForTest: typeof import("./setup-registry.test-fixtures.js").setPluginSetupRegistryModuleLoaderFactoryForTest;
 
 function forceNodeRuntimeVersionsForTest(): () => void {
   const originalVersions = process.versions;
@@ -203,7 +201,7 @@ function firstRecordArg(mock: { mock: { calls: ReadonlyArray<ReadonlyArray<unkno
 }
 
 afterEach(() => {
-  setPluginSetupRegistryModuleLoaderFactoryForTest?.(undefined);
+  setPluginSetupRegistryModuleLoaderFactoryForTest(undefined);
   cleanupTrackedTempDirs(tempDirs);
 });
 
@@ -216,11 +214,18 @@ describe("setup-registry module loader", () => {
 
   beforeAll(async () => {
     resetRegistryJitiMocks();
+    // The non-isolated plugin shard may cache this owner through a sibling first.
+    // Refresh it once after this file's hoisted mocks, then reuse it for every case.
     vi.resetModules();
-    const module = await import("./setup-registry.js");
-    const fixtures = await import("./setup-registry.test-fixtures.js");
-    fixtures.setPluginSetupRegistryModuleLoaderFactoryForTest(mocks.createJiti);
-    fixtures.clearPluginSetupRegistryCache();
+    ({
+      resolvePluginSetupRegistry,
+      resolvePluginSetupProviderCore,
+      resolvePluginSetupCliBackend,
+      runPluginSetupConfigMigrations,
+    } = await import("./setup-registry.js"));
+    ({ clearPluginSetupRegistryCache, setPluginSetupRegistryModuleLoaderFactoryForTest } =
+      await import("./setup-registry.test-fixtures.js"));
+    setPluginSetupRegistryModuleLoaderFactoryForTest(mocks.createJiti);
     const pluginRoot = makeTempDir();
     fs.writeFileSync(path.join(pluginRoot, "setup-api.js"), "export default {};\n", "utf-8");
     mocks.loadPluginManifestRegistry.mockReturnValue({
@@ -231,7 +236,7 @@ describe("setup-registry module loader", () => {
 
     try {
       withMockedWindowsPlatform(() => {
-        module.resolvePluginSetupRegistry({
+        resolvePluginSetupRegistry({
           workspaceDir: pluginRoot,
           env: {},
         });
@@ -247,22 +252,12 @@ describe("setup-registry module loader", () => {
       filename: mockArg(mocks.createJiti, 0, 0),
       options: requireRecord(mockArg(mocks.createJiti, 0, 1)),
     };
-    fixtures.setPluginSetupRegistryModuleLoaderFactoryForTest(undefined);
+    setPluginSetupRegistryModuleLoaderFactoryForTest(undefined);
   });
 
-  beforeEach(async () => {
+  beforeEach(() => {
     resetRegistryJitiMocks();
-    vi.resetModules();
-    ({
-      resolvePluginSetupRegistry,
-      resolvePluginSetupProviderCore,
-      resolvePluginSetupCliBackend,
-      runPluginSetupConfigMigrations,
-    } = await import("./setup-registry.js"));
-    ({ clearPluginSetupRegistryCache, setPluginSetupRegistryModuleLoaderFactoryForTest } =
-      await import("./setup-registry.test-fixtures.js"));
     setPluginSetupRegistryModuleLoaderFactoryForTest(mocks.createJiti);
-    clearPluginSetupRegistryCache();
   });
 
   it("uses the runtime-supported source-transform boundary on Windows for setup-api modules", () => {