fix(artifacts): preserve NIB key and class name identity (#2109)

Co-authored-by: morluto <76467478+morluto@users.noreply.github.com>

src/artifacts/apple/NibArchive.test.ts

@@ -36,6 +36,22 @@ const archiveWithOverlappingObjectRanges = (objectCount: number): Buffer => {
 };
 
 describe("NIBArchive decoder", () => {
+  it("keeps leading U+FEFF in length-prefixed keys and class names", () => {
+    const archive = encodeArchive({
+      classes: ["\uFEFFWidget"],
+      objects: [{ classIndex: 0, values: { count: 1, "\uFEFFcount": 2 } }],
+    });
+    expect(decodeNibArchive(archive).objects).toEqual([
+      {
+        id: 0,
+        class_name: "\uFEFFWidget",
+        values: { count: 1, "\uFEFFcount": 2 },
+      },
+    ]);
+    const invalid = Buffer.from(archive);
+    invalid[invalid.indexOf(Buffer.from("\uFEFFcount"))] = 0xff;
+    expect(() => decodeNibArchive(invalid)).toThrow(/not valid UTF-8/u);
+  });
   it("decodes bounded object, key, class, and reference tables", () => {
     const archive = encodeArchive({
       classes: ["NSView\0", "NSString\0"],

tests/boundary/filesystem/interfaceBuilderBundle.test.ts

@@ -696,6 +696,49 @@ describe("NIB projection byte amplification", () => {
   });
 });
 
+cliTest(
+  "compiled CLI preserves distinct NIB keys and class identity",
+  async ({ cli }) => {
+    const root = await createTestTempDirectory("rea-nib-name-identity-");
+    const bundle = join(root, "Example.app");
+    const resources = join(bundle, "Contents", "Resources");
+    await mkdir(resources, { recursive: true });
+    await mkdir(join(bundle, "Contents", "MacOS"), { recursive: true });
+    await writeFile(
+      join(bundle, "Contents", "MacOS", "App"),
+      thinMach(0xfeedfacf, 0x0100000c),
+    );
+    await writeFile(
+      join(bundle, "Contents", "Info.plist"),
+      "<plist><dict><key>CFBundleExecutable</key><string>App</string></dict></plist>",
+    );
+    await writeFile(
+      join(resources, "Identity.nib"),
+      encodeNibArchiveFixture({
+        classes: ["\uFEFFWidget"],
+        objects: [{ classIndex: 0, values: { count: 1, "\uFEFFcount": 2 } }],
+      }),
+    );
+    const output = await cli.run({
+      arguments: ["decode-interface-builder", bundle, "--json"],
+      environment: { REA_LOG_LEVEL: "silent", REA_ANALYSIS_PROVIDER: "auto" },
+    });
+    expect(output.exitCode, output.stderr).toBe(0);
+    const result = interfaceBuilderAnalysisSchema.parse(
+      parseEvidence(output.json).normalized_result,
+    );
+    expect(result.graph.nodes).toContainEqual(
+      expect.objectContaining({
+        attributes: expect.objectContaining({
+          class_name: "\uFEFFWidget",
+          nibValues: { count: 1, "\uFEFFcount": 2 },
+        }),
+      }),
+    );
+    expect(JSON.stringify(result)).toContain("\uFEFFWidget");
+  },
+);
+
 cliTest(
   "compiled CLI preserves a good archive and reports repeated key and data omissions",
   async ({ cli }) => {