Initial Commit

packages/testkit/testing/testing-dom/tests/tree-shake.test.ts

@@ -0,0 +1,51 @@
+/**
+ * Tree-shake guard — verify subpaths don't drag unrelated modules.
+ */
+import { readFile } from "node:fs/promises";
+import { dirname, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+import { describe, expect, it } from "../src/runner/index.js";
+
+const here = dirname(fileURLToPath(import.meta.url));
+const distRoot = resolve(here, "..", "dist");
+
+async function distExists(): Promise<boolean> {
+    try {
+        await readFile(resolve(distRoot, "index.js"), "utf8");
+        return true;
+    } catch {
+        return false;
+    }
+}
+
+async function readDist(rel: string): Promise<string> {
+    return readFile(resolve(distRoot, rel), "utf8");
+}
+
+describe("tree-shake guards", () => {
+    it("matchers subpath does not pull renderComponent", {
+        timeout: 10000,
+    }, async () => {
+        if (!(await distExists())) return;
+        const text = await readDist("matchers/matchers.js");
+        expect(text).not.toMatch(/function\s+renderComponent\b/);
+        expect(text).not.toMatch(/class\s+RenderError\b/);
+    });
+
+    it("user/setup-user does not pull jest-dom matchers", {
+        timeout: 10000,
+    }, async () => {
+        if (!(await distExists())) return;
+        const text = await readDist("user/setup-user.js");
+        expect(text).not.toMatch(/toBeInTheDocument/);
+        expect(text).not.toMatch(/jest-dom/);
+    });
+
+    it("polyfills subpath has no functional surface", {
+        timeout: 10000,
+    }, async () => {
+        if (!(await distExists())) return;
+        const text = await readDist("setup/polyfills.js");
+        expect(text).not.toMatch(/export\s+(?:const|function|class)/);
+    });
+});