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+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+//
+// [ADR-0131 D9] The organization census of a self-registration on a WALLED
+// boot (`group` and `isolated`), end to end on the real stack with the audit
+// and email plugins composed together. The `single` leg is
+// `signup-organization-census.dogfood.test.ts`; this file is its walled
+// sibling, one boot per posture.
+//
+// The journey is the whole sign-up a walled deployment sees: a stranger
+// self-registers (the verification mail is sent), creates their organization
+// (their first membership), and invites a second stranger (the invitation
+// mail is sent), who signs up and accepts it (their first membership).
+// Three framework writers act on tenant-column objects along the way, and on
+// a wall none of them may fall back to an organization-less row:
+//
+//   - the self-registration grant (`sys_user_permission_set`) settles on the
+//     self-registrant's FIRST MEMBERSHIP, owned by that membership's
+//     organization (ADR-0131 D3) — never at sign-up, when there is no
+//     organization yet; the invitee is admitted by the invitation, not by the
+//     open posture, and is owed no declared set;
+//   - the activity writer (`sys_activity`) stamps the organization of the
+//     record it is about, and writes NO row about a record that has none
+//     (ADR-0131 D9; ruling of record 6257510973 item 3, Q3 A);
+//   - the verification mail is identity mail, written to
+//     `sys_identity_email`, which carries no organization column (ADR-0131
+//     D7; ruling of record 6257510973, Q2 A); the invitation mail is tenant
+//     mail, written to `sys_email`, owned by the inviting organization.
+//
+// The census reads the STORE, not the registry: every table of the sqlite
+// database that carries an `organization_id` column — activity shards and
+// tables no object names included — is derived from the schema at run time,
+// so a new table joins the census on its own. Since 18.x the engine creates a
+// tenant column NOT NULL, so "0 NULL rows" alone could hold vacuously (a
+// refused write leaves no row, and no NULL either); every writer's own row is
+// therefore also required to EXIST and to name the organization the user
+// joined.
+//
+// The boot is `multiTenant: 'posture-only'`: a real, non-degraded walled
+// posture. Every writer here keys on the posture (whether an organization is
+// derivable), never on row isolation, so the stand-in's lack of a row wall
+// measures nothing away. `OS_TENANCY_POSTURE` selects `group`.
+
+import { describe, it, expect, beforeAll, afterAll } from 'vitest';
+import crmStack from '@objectstack/example-crm';
+import { bootStack, type VerifyStack } from '@objectstack/verify';
+import { EmailServicePlugin } from '@objectstack/plugin-email';
+import { AuditPlugin } from '@objectstack/plugin-audit';
+
+const SYS = { context: { isSystem: true } };
+const SET = 'member_default';
+const PASSWORD = 'Census-Passw0rd!';
+
+/** A transport that accepts every message, so every mail persists as sent. */
+const acceptingTransport = {
+  async send() {
+    return { messageId: `census-${Math.random().toString(36).slice(2, 10)}` };
+  },
+};
+
+type Row = Record<string, unknown>;
+
+for (const posture of ['group', 'isolated'] as const) {
+  describe(`[ADR-0131 D9] ${posture}: a walled self-registration leaves no organization-less row`, () => {
+    const REGISTRANT = `census-registrant-${posture}@dogfood.test`;
+    const INVITEE = `census-invitee-${posture}@dogfood.test`;
+    const SLUG = `census-${posture}`;
+    let stack: VerifyStack;
+    let ql: any;
+    let orgId: string;
+    let registrantId: string;
+    let inviteeId: string;
+    let invitationId: string;
+    /** `table/id` of every row the store held on a tenant-column table BEFORE the journey. */
+    const beforeJourney = new Set<string>();
+    const previous = process.env.OS_TENANCY_POSTURE;
+
+    /** A raw statement on the default datasource — the store as it is, below every engine read path. */
+    const sql = async (statement: string): Promise<Row[]> => {
+      const rows = await ql.getDriverForObject('sys_user').execute(statement);
+      return Array.isArray(rows) ? (rows as Row[]) : [];
+    };
+    /** Every table of the store that carries an `organization_id` column, read from the schema now. */
+    const tenantColumnTables = async (): Promise<string[]> => {
+      const tables = (await sql("SELECT name FROM sqlite_master WHERE type = 'table' ORDER BY name")).map((r) => String(r.name));
+      const out: string[] = [];
+      for (const table of tables) {
+        const columns = await sql(`PRAGMA table_info("${table}")`);
+        if (columns.some((c) => c.name === 'organization_id')) out.push(table);
+      }
+      return out;
+    };
+    /** Every row of every tenant-column table, keyed `table/id`. */
+    const storeRows = async (): Promise<Map<string, Row & { table: string }>> => {
+      const out = new Map<string, Row & { table: string }>();
+      for (const table of await tenantColumnTables()) {
+        for (const row of await sql(`SELECT * FROM "${table}"`)) out.set(`${table}/${String(row.id)}`, { ...row, table });
+      }
+      return out;
+    };
+    const journeyRows = async () => [...(await storeRows()).entries()].filter(([key]) => !beforeJourney.has(key)).map(([, row]) => row);
+    const userIdOf = async (email: string): Promise<string> => {
+      const user = await ql.findOne('sys_user', { where: { email }, ...SYS });
+      expect(user?.id, `${email} exists`).toBeTruthy();
+      return String(user.id);
+    };
+    /** Self-register through the public door; the address is then marked verified in place, so the user can sign in. */
+    const selfRegister = async (email: string, name: string): Promise<{ id: string; token: string }> => {
+      const signedUp = await stack.api('/auth/sign-up/email', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ email, password: PASSWORD, name }),
+      });
+      expect(signedUp.status, `sign-up ${email}: ${await signedUp.clone().text()}`).toBe(200);
+      const id = await userIdOf(email);
+      await ql.update('sys_user', { id, email_verified: true }, SYS);
+      return { id, token: await stack.signIn(email, PASSWORD) };
+    };
+
+    beforeAll(async () => {
+      process.env.OS_TENANCY_POSTURE = posture;
+      stack = await bootStack(crmStack as never, {
+        multiTenant: 'posture-only',
+        extraPlugins: [new AuditPlugin(), new EmailServicePlugin({
+          transport: acceptingTransport as never,
+          defaultFrom: { address: 'no-reply@example.test', name: 'Census' },
+        })],
+      });
+      const adminToken = await stack.signIn();
+      ql = await stack.kernel.getServiceAsync<any>('objectql');
+
+      // An open audience: a stranger self-registers, is owed the declared set,
+      // and is sent the verification mail the open posture requires.
+      const opened = await stack.raw('/api/settings/auth', {
+        method: 'PUT',
+        headers: { 'Content-Type': 'application/json', Authorization: `Bearer ${adminToken}` },
+        body: JSON.stringify({ values: { audience_posture: 'open', audience_self_registration_permission_set: SET } }),
+      });
+      expect(opened.status, `open the audience: ${await opened.clone().text()}`).toBe(200);
+
+      // The census is of what the JOURNEY writes; the boot's own rows are set
+      // aside here, by table and id (they are still read by the whole-store
+      // NULL census below).
+      for (const key of (await storeRows()).keys()) beforeJourney.add(key);
+
+      // 1. The registrant self-registers and creates their organization.
+      const registrant = await selfRegister(REGISTRANT, 'Census Registrant');
+      registrantId = registrant.id;
+      const created = await stack.apiAs(registrant.token, 'POST', '/auth/organization/create', { name: `Census ${posture}`, slug: SLUG });
+      expect(created.status, `organization/create: ${await created.clone().text()}`).toBe(200);
+      orgId = String(((await created.json()) as { id?: string }).id ?? '');
+      expect(orgId, 'the organization was created').not.toBe('');
+
+      // 2. They invite a second stranger, who self-registers and accepts.
+      const invited = await stack.apiAs(registrant.token, 'POST', '/auth/organization/invite-member', {
+        email: INVITEE, role: 'member', organizationId: orgId,
+      });
+      expect(invited.status, `invite-member: ${await invited.clone().text()}`).toBe(200);
+      invitationId = String(((await invited.json()) as { id?: string }).id ?? '');
+      expect(invitationId, 'the invitation was issued').not.toBe('');
+      const invitee = await selfRegister(INVITEE, 'Census Invitee');
+      inviteeId = invitee.id;
+      const accepted = await stack.apiAs(invitee.token, 'POST', '/auth/organization/accept-invitation', { invitationId });
+      expect(accepted.status, `accept-invitation: ${await accepted.clone().text()}`).toBe(200);
+    }, 180_000);
+
+    afterAll(async () => {
+      await stack?.stop?.();
+      if (previous === undefined) delete process.env.OS_TENANCY_POSTURE;
+      else process.env.OS_TENANCY_POSTURE = previous;
+    });
+
+    it('guard: a real walled posture, and each registrant\'s first membership is the organization of the journey', async () => {
+      const tenancy = await stack.kernel.getServiceAsync<{ posture: string; degraded: boolean; isolationActive: boolean }>('tenancy');
+      expect(tenancy.posture).toBe(posture);
+      expect(tenancy.degraded).toBe(false);
+      expect(tenancy.isolationActive).toBe(true);
+      for (const userId of [registrantId, inviteeId]) {
+        const memberships = await ql.find('sys_member', { where: { user_id: userId }, ...SYS });
+        expect(memberships.map((m: Row) => m.organization_id), `${userId}: memberships`).toEqual([orgId]);
+      }
+      // The census's own reach: the store's tenant-column tables include every
+      // one the three writers write.
+      const tables = await tenantColumnTables();
+      for (const table of ['sys_user_permission_set', 'sys_email', 'sys_member', 'sys_invitation']) expect(tables).toContain(table);
+      expect(tables.some((t) => t === 'sys_activity' || t.startsWith('sys_activity__')), 'an activity table carries the column').toBe(true);
+    });
+
+    it('the whole store holds 0 rows without an organization on every table that carries the column', async () => {
+      const orgLess = [...(await storeRows()).values()]
+        .filter((r) => r.organization_id == null || r.organization_id === '')
+        .map((r) => `${r.table}/${String(r.id)}`);
+      expect(orgLess, 'rows without an organization').toEqual([]);
+    });
+
+    it('every row the journey wrote on a tenant-column table names the organization the users joined', async () => {
+      const written = await journeyRows();
+      expect(written.length, 'the journey wrote tenant rows').toBeGreaterThan(0);
+      const foreign = written.filter((r) => r.organization_id !== orgId).map((r) => `${r.table}/${String(r.id)} -> ${String(r.organization_id)}`);
+      expect(foreign, 'rows owned by an organization other than the journey\'s').toEqual([]);
+    });
+
+    it('the grant writer: the self-registrant holds exactly one declared grant, owned by their first membership', async () => {
+      const grants = await ql.find('sys_user_permission_set', { where: { user_id: registrantId }, ...SYS });
+      expect(grants.filter((g: Row) => g.permission_set === SET).map((g: Row) => g.organization_id), 'the declared grant').toEqual([orgId]);
+      // The creator's `organization_admin` (the auto org-admin grant) rides
+      // the same membership; every grant names the organization.
+      expect(grants.filter((g: Row) => g.organization_id !== orgId), 'grants outside the organization').toEqual([]);
+      // The invitee was admitted by the invitation, not by the open posture, so
+      // is owed no declared set (`decideAudienceAdmission`); whatever it holds
+      // names the organization too.
+      const inviteeGrants = await ql.find('sys_user_permission_set', { where: { user_id: inviteeId }, ...SYS });
+      expect(inviteeGrants.filter((g: Row) => g.permission_set === SET), 'the invitee holds no declared grant').toEqual([]);
+      expect(inviteeGrants.filter((g: Row) => g.organization_id !== orgId), 'invitee grants outside the organization').toEqual([]);
+    });
+
+    it('the activity writer: activity about each grant and about the invitation mail names the organization', async () => {
+      const written = await journeyRows();
+      const activity = written.filter((r) => r.table === 'sys_activity' || r.table.startsWith('sys_activity__'));
+      const grants = await ql.find('sys_user_permission_set', { where: { user_id: registrantId }, ...SYS });
+      expect(grants.map((g: Row) => g.permission_set), 'the registrant\'s grants').toContain(SET);
+      for (const grant of grants) {
+        const about = activity.filter((a) => a.object_name === 'sys_user_permission_set' && a.record_id === grant.id);
+        expect(about.length, `activity about the grant ${String(grant.id)}`).toBeGreaterThan(0);
+        expect(about.map((a) => a.organization_id)).toEqual(about.map(() => orgId));
+      }
+      const [invitationMail] = await ql.find('sys_email', { where: { related_object: 'sys_invitation', related_id: invitationId }, ...SYS });
+      expect(invitationMail?.id, 'the invitation mail persisted').toBeTruthy();
+      const aboutMail = activity.filter((a) => a.object_name === 'sys_email' && a.record_id === invitationMail.id);
+      expect(aboutMail.length, 'activity about the invitation mail').toBeGreaterThan(0);
+      expect(aboutMail.map((a) => a.organization_id)).toEqual(aboutMail.map(() => orgId));
+      // A record with no organization of its own (the registrant) on a wall
+      // takes none: no activity row about it, never a NULL one.
+      expect(activity.filter((a) => a.object_name === 'sys_user' && [registrantId, inviteeId].includes(String(a.record_id)))).toEqual([]);
+    });
+
+    it('the mail writers: the invitation is tenant mail owned by the organization; each verification mail is identity mail', async () => {
+      const [invitationMail] = await ql.find('sys_email', { where: { related_object: 'sys_invitation', related_id: invitationId }, ...SYS });
+      expect(invitationMail?.organization_id).toBe(orgId);
+      for (const userId of [registrantId, inviteeId]) {
+        const identity = await ql.find('sys_identity_email', { where: { related_object: 'sys_user', related_id: userId }, ...SYS });
+        expect(identity.length, `${userId}: the verification mail persisted, in the identity-mail log`).toBeGreaterThan(0);
+        expect(identity.every((m: Row) => !('organization_id' in m))).toBe(true);
+        const tenantMail = await ql.find('sys_email', { where: { related_object: 'sys_user', related_id: userId }, ...SYS });
+        expect(tenantMail, `${userId}: no verification mail in the tenant mail log`).toEqual([]);
+      }
+      const identityColumns = (await sql('PRAGMA table_info("sys_identity_email")')).map((c) => c.name);
+      expect(identityColumns.length, 'sys_identity_email is in the store').toBeGreaterThan(0);
+      expect(identityColumns).not.toContain('organization_id');
+    });
+  });
+}