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+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * `POST /packages/:id/adopt-orphans` — the ADR-0070 D2 read-only rule at the
+ * orphan-adoption door (#24813).
+ *
+ * ## The defect
+ *
+ * The arm asked `requireManageMetadata` and the walled refusal, and then called
+ * `protocol.reassignOrphanedMetadata({ targetPackageId: id })`, which asks no
+ * writability question of its own: it rebinds every package-less
+ * `sys_metadata` row to whatever id it is handed. So a `manage_metadata`
+ * holder could bind the environment's loose items INTO a package the
+ * deployment ships — booted by code, installed from the marketplace, or a
+ * stored row whose manifest `scope` is `system` / `cloud` — and the door
+ * answered `200` with the rows it moved. Every other state-changing arm on the
+ * domain (install-overwrite, disable, publish, revert, the manifest PATCH and
+ * delete) refuses that same id `422 WRITABLE_PACKAGE_REQUIRED`.
+ *
+ * ## What is asserted, and why it is not the status alone
+ *
+ * The harm is the rebinding, so every refusal reads the rows back: the
+ * orphans the real producer minted (a package-less `saveMetaItem`, which still
+ * lands `package_id = NULL` today) are still package-less after the refusal,
+ * and the protocol's `reassignOrphanedMetadata` was never called. The store is
+ * REAL — better-sqlite3 `:memory:`, the real `sys_metadata*` objects, a real
+ * `ObjectStackProtocolImplementation` over a real `ObjectQL` — so the rows are
+ * the store's, not a double's. The code-booted and marketplace ids are booted
+ * through the engine's own `registerApp`; the two scope-only ids are installed
+ * the way `sys_packages` hydration installs a stored row (`source:
+ * 'authored'`, no booted manifest), so their refusal can only come from the
+ * scope signal.
+ *
+ * ## Order
+ *
+ * The gate sits where its siblings put it: after the capability gate and the
+ * walled refusal (both `403`, both still answer first on a read-only id), and
+ * before the protocol is resolved, so a read-only id answers `422` even on a
+ * deployment whose protocol cannot adopt (`501` for a writable id there).
+ *
+ * ## The gate is not an outage
+ *
+ * CONTROL: a writable package still adopts (`200`, and the rows really move),
+ * and an id nothing installed is writable by the predicate's own rule, so it
+ * still reaches the protocol, which binds the orphans to it exactly as before.
+ */
+
+import { describe, it, expect, vi, afterEach } from 'vitest';
+import { ObjectQL } from '@objectstack/objectql';
+import { SqlDriver } from '@objectstack/driver-sql';
+import { ObjectStackProtocolImplementation } from '@objectstack/metadata-protocol';
+import { SysMetadata, SysMetadataHistoryObject, SysMetadataAuditObject } from '@objectstack/platform-objects/metadata';
+import { HttpDispatcher } from '../http-dispatcher.js';
+
+/** Booted by the deployment's code: `registerApp`, default source `'code'`. */
+const CODE_BOOTED = 'com.acme.codepkg';
+/** Installed from the marketplace: `registerApp(…, 'marketplace')`. */
+const MARKETPLACE = 'com.acme.marketpkg';
+/** A stored row whose manifest declares `scope: 'system'`; nothing booted it. */
+const SYSTEM_SCOPED = 'com.acme.systempkg';
+/** A stored row whose manifest declares `scope: 'cloud'`; nothing booted it. */
+const CLOUD_SCOPED = 'com.acme.cloudpkg';
+/** An org's own base. */
+const AUTHORED = 'com.acme.authoredpkg';
+/** An id nothing has installed. */
+const UNKNOWN = 'com.acme.nopkg';
+/** `registry.registerObject` requires a package id (see the sibling real-stack tests). */
+const TEST_PACKAGE_ID = 'objectstack-test';
+
+/** The loose items the real producer leaves behind. */
+const ORPHANS = ['loose_grid', 'loose_board'] as const;
+
+const manifest = (id: string, extra: Record<string, unknown> = {}) => ({
+    id,
+    name: id,
+    version: '1.0.0',
+    type: 'app',
+    ...extra,
+});
+
+const TASK = {
+    name: 'task',
+    label: 'Task',
+    fields: {
+        id: { name: 'id', type: 'text' as const, primaryKey: true, label: 'ID' },
+        name: { name: 'name', type: 'text' as const, label: 'Name' },
+    },
+};
+
+const view = (name: string) => ({
+    name,
+    label: name,
+    object: 'task',
+    viewKind: 'list',
+    columns: [{ field: 'name', label: 'Name' }],
+});
+
+const silentLogger: any = {
+    debug() {}, info() {}, warn() {}, error() {}, trace() {}, fatal() {},
+    child() { return silentLogger; },
+};
+
+const liveEngines: ObjectQL[] = [];
+afterEach(async () => {
+    while (liveEngines.length) {
+        try { await liveEngines.pop()?.destroy(); } catch { /* noop */ }
+    }
+});
+
+interface BootOptions {
+    /** Compose a protocol that cannot adopt (no `reassignOrphanedMetadata`). */
+    protocolWithoutAdoption?: boolean;
+    /** Compose a `tenancy` service answering this posture. */
+    posture?: 'isolated' | 'group';
+}
+
+/** The composed door over a real store, with the orphans already minted. */
+async function boot(options: BootOptions = {}) {
+    const engine = new ObjectQL({ logger: silentLogger });
+    liveEngines.push(engine);
+    (engine.registry as unknown as { logLevel: string }).logLevel = 'silent';
+    engine.registerDriver(new SqlDriver({
+        client: 'better-sqlite3',
+        connection: { filename: ':memory:' },
+        useNullAsDefault: true,
+    }), true);
+    await engine.init();
+    engine.registry.registerObject(TASK as any, TEST_PACKAGE_ID);
+    engine.registry.registerObject(SysMetadata as any, TEST_PACKAGE_ID);
+    engine.registry.registerObject(SysMetadataHistoryObject as any, TEST_PACKAGE_ID);
+    engine.registry.registerObject(SysMetadataAuditObject as any, TEST_PACKAGE_ID);
+    await engine.syncSchemas();
+
+    engine.registerApp(manifest(CODE_BOOTED));
+    engine.registerApp(manifest(MARKETPLACE), undefined, 'marketplace');
+    engine.registry.installPackage(manifest(SYSTEM_SCOPED, { scope: 'system' }) as any, 'authored');
+    engine.registry.installPackage(manifest(CLOUD_SCOPED, { scope: 'cloud' }) as any, 'authored');
+    engine.registry.installPackage(manifest(AUTHORED, { scope: 'project' }) as any, 'authored');
+
+    const protocol = new ObjectStackProtocolImplementation(engine as any);
+    // The real producer of an orphan: a save naming no package.
+    for (const name of ORPHANS) {
+        await protocol.saveMetaItem({ type: 'view', name, item: view(name), mode: 'publish' });
+    }
+    const adopt = vi.spyOn(protocol, 'reassignOrphanedMetadata');
+
+    const served = options.protocolWithoutAdoption
+        ? { saveMetaItem: protocol.saveMetaItem.bind(protocol) }
+        : protocol;
+    const services: Record<string, unknown> = { protocol: served, objectql: engine };
+    if (options.posture) services.tenancy = { posture: options.posture };
+    const get = (name: string) => services[name] ?? null;
+    const kernel: any = { context: { getService: get }, getService: get, getServiceAsync: async (n: string) => get(n) };
+    const dispatcher = new HttpDispatcher(kernel);
+
+    /** Each loose item's binding, read off the store. */
+    const bindings = async (): Promise<Record<string, unknown>> => {
+        const rows = (await engine.find('sys_metadata', { where: { type: 'view' } })) as any[];
+        return Object.fromEntries(
+            rows.filter((r) => (ORPHANS as readonly string[]).includes(r.name)).map((r) => [r.name, r.package_id ?? null]),
+        );
+    };
+
+    return { engine, dispatcher, adopt, bindings };
+}
+
+type Caller = Record<string, unknown>;
+/** Holds `manage_metadata`; the operator rung, so no wall refuses it. */
+const ADMIN: Caller = { userId: 'u_pkg_admin', systemPermissions: ['manage_metadata', 'studio.access'], posture: 'PLATFORM_ADMIN' };
+/** Signed in, without `manage_metadata`. */
+const NO_CAPABILITY: Caller = { userId: 'u_reader', systemPermissions: ['studio.access'] };
+/** An organization's `manage_metadata` holder below the operator rung. */
+const TENANT_AUTHOR: Caller = { userId: 'u_tenant', tenantId: 'org_a', systemPermissions: ['manage_metadata'], posture: 'TENANT_ADMIN' };
+
+type Door = Awaited<ReturnType<typeof boot>>;
+const adoptInto = async (d: Door, id: string, caller: Caller = ADMIN) => {
+    const r = await d.dispatcher.handlePackages(
+        `/${encodeURIComponent(id)}/adopt-orphans`, 'POST', {}, {},
+        { request: {}, environmentId: 'pkg-adopt-orphans-readonly-test', executionContext: caller } as any,
+    );
+    expect(r.handled).toBe(true);
+    return { status: r.response?.status, body: r.response?.body as any };
+};
+
+const UNBOUND = Object.fromEntries(ORPHANS.map((n) => [n, null]));
+const boundTo = (id: string) => Object.fromEntries(ORPHANS.map((n) => [n, id]));
+
+// ══════════════════════════════════════════════════════════════════════════════
+// 1. REFUSED: adopting into a read-only package binds nothing
+// ══════════════════════════════════════════════════════════════════════════════
+
+const READ_ONLY: Array<{ label: string; id: string; booted: boolean }> = [
+    { label: 'code-booted (registerApp)', id: CODE_BOOTED, booted: true },
+    { label: 'marketplace-installed (registerApp, marketplace)', id: MARKETPLACE, booted: true },
+    { label: 'system-scoped stored row (scope signal only)', id: SYSTEM_SCOPED, booted: false },
+    { label: 'cloud-scoped stored row (scope signal only)', id: CLOUD_SCOPED, booted: false },
+];
+
+describe('POST /packages/:id/adopt-orphans on a read-only package is refused', () => {
+    for (const pkg of READ_ONLY) {
+        it(`422s the ${pkg.label} package and binds nothing`, async () => {
+            const d = await boot();
+            expect(await d.bindings(), 'precondition: the producer left orphans').toEqual(UNBOUND);
+            expect((d.engine as unknown as { manifests: Map<string, unknown> }).manifests.has(pkg.id),
+                'precondition: the boot signal').toBe(pkg.booted);
+
+            const r = await adoptInto(d, pkg.id);
+
+            expect(r.status).toBe(422);
+            expect(r.body?.success).toBe(false);
+            expect(r.body?.error?.code).toBe('WRITABLE_PACKAGE_REQUIRED');
+            expect(r.body?.error?.httpStatus).toBe(422);
+            expect(r.body?.error?.details?.packageId).toBe(pkg.id);
+            expect(r.body?.error?.details?.docs).toBe('docs/adr/0070-package-first-authoring.md');
+            // Nothing was rebound: the protocol was never asked, and the rows say so.
+            expect(d.adopt).not.toHaveBeenCalled();
+            expect(await d.bindings()).toEqual(UNBOUND);
+        }, 30_000);
+    }
+});
+
+// ══════════════════════════════════════════════════════════════════════════════
+// 2. ORDER: which refusal answers when more than one applies to a read-only id
+// ══════════════════════════════════════════════════════════════════════════════
+
+describe('POST /packages/:id/adopt-orphans — the gate\'s place among the refusals', () => {
+    it('a caller without manage_metadata is refused 403 by the capability gate first', async () => {
+        const d = await boot();
+
+        const r = await adoptInto(d, CODE_BOOTED, NO_CAPABILITY);
+
+        expect(r.status).toBe(403);
+        expect(r.body?.error?.code).not.toBe('WRITABLE_PACKAGE_REQUIRED');
+        expect(String(r.body?.error?.message)).toContain('manage_metadata');
+        expect(d.adopt).not.toHaveBeenCalled();
+        expect(await d.bindings()).toEqual(UNBOUND);
+    }, 30_000);
+
+    it('under a wall, a tenant holder is refused 403 PERMISSION_DENIED by the walled refusal first', async () => {
+        const d = await boot({ posture: 'isolated' });
+
+        const r = await adoptInto(d, CODE_BOOTED, TENANT_AUTHOR);
+
+        expect(r.status).toBe(403);
+        expect(r.body?.error?.code).toBe('PERMISSION_DENIED');
+        expect(String(r.body?.error?.message)).toContain('tenancy posture');
+        expect(d.adopt).not.toHaveBeenCalled();
+        expect(await d.bindings()).toEqual(UNBOUND);
+    }, 30_000);
+
+    it('the gate precedes the protocol: a read-only id answers 422 where a writable id answers 501', async () => {
+        const d = await boot({ protocolWithoutAdoption: true });
+
+        const readOnly = await adoptInto(d, CODE_BOOTED);
+        expect(readOnly.status).toBe(422);
+        expect(readOnly.body?.error?.code).toBe('WRITABLE_PACKAGE_REQUIRED');
+
+        const writable = await adoptInto(d, AUTHORED);
+        expect(writable.status).toBe(501);
+        expect(writable.body?.error?.code).not.toBe('WRITABLE_PACKAGE_REQUIRED');
+        expect(await d.bindings()).toEqual(UNBOUND);
+    }, 30_000);
+});
+
+// ══════════════════════════════════════════════════════════════════════════════
+// 3. CONTROL: the gate is not an outage
+// ══════════════════════════════════════════════════════════════════════════════
+
+describe('POST /packages/:id/adopt-orphans still adopts into what an org owns', () => {
+    it('a writable package adopts: 200, and every orphan is really bound to it', async () => {
+        const d = await boot();
+
+        const r = await adoptInto(d, AUTHORED);
+
+        expect(r.status).toBe(200);
+        expect(r.body?.data).toMatchObject({ success: true, reassignedCount: ORPHANS.length, targetPackageId: AUTHORED });
+        expect(d.adopt).toHaveBeenCalledTimes(1);
+        expect(await d.bindings()).toEqual(boundTo(AUTHORED));
+    }, 30_000);
+
+    it('an id nothing installed is writable by the predicate\'s own rule, so it still reaches the protocol, as before', async () => {
+        const d = await boot();
+        expect(d.engine.registry.getPackage(UNKNOWN), 'precondition: nothing installed it').toBeUndefined();
+
+        const r = await adoptInto(d, UNKNOWN);
+
+        expect(r.status).toBe(200);
+        expect(r.body?.error?.code).toBeUndefined();
+        expect(d.adopt).toHaveBeenCalledTimes(1);
+        expect(await d.bindings()).toEqual(boundTo(UNKNOWN));
+    }, 30_000);
+});