@@ -0,0 +1,15 @@
+---
+"@objectstack/lint": patch
+---
+
+The runtime publish gate no longer charges a write with a stored sibling's finding that only shows when the written item is present. Re-saving a master object with only its label changed answered `422 INVALID_METADATA` for a stored detail the author never touched: a detail's `lookupColumns` entry naming no field of the master, or a detail's `readonlyWhen` read through `parent`.
+
+Clause-②: no
+
+- On an update into a context collection (`object`, `permission`, `book`, `dataset`) the gate also judges the stored universe: the live collections with the written item's stored self in place. A finding located on another entry that the stored universe already holds is not this write's.
+- A finding located on the written item itself is judged as before, even when the stored row carries the same finding. Re-saving a row is writing it.
+- A write that newly breaks a sibling is still refused, for example removing the master field a detail's `lookupColumns` names.
+- A create is judged as before.
+- On a permission write the same change drops a stored detail's `security-master-detail-ungranted` advisory from a label-only re-save of the tenant's only permission set.
+- A finding whose path names no entry the gate can locate keeps the previous verdict.
+- ⛔ Nothing you author changes, and no export or signature changes.
@@ -0,0 +1,341 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * #22118 — the object-write differential judges a sibling's finding against
+ * the STORED universe, which includes the written object's stored self.
+ *
+ * ## The state this closes
+ *
+ * `buildRuntimeWriteSnapshots` drops the written item's stored self from the
+ * baseline, so the baseline is the universe WITHOUT the written object. A
+ * stored sibling whose finding only shows when that object is present — a
+ * detail's `lookupColumns` entry, judged against its master only when the
+ * master is in the snapshot; a detail's `readonlyWhen` read through `parent`
+ * — therefore had its finding absent from the baseline and present in the
+ * candidate, and a label-only save of the master answered 422 for a detail
+ * the author never touched. That contradicts the gate's own contract: a
+ * stored object already in violation is never charged to someone else's write.
+ *
+ * ## The ruling this pins
+ *
+ * - The baseline keeps the written object's stored self: a finding located on
+ *   another object that already exists against the stored universe is not new.
+ * - Findings located on the written object itself are judged as before.
+ * - No per-rule exemptions: every door rule reads the one differential, so
+ *   the location is read off the finding's path spelling, never its rule.
+ *
+ * The protocol-level half — the same verdicts through the real `saveMetaItem`,
+ * with the 422 envelope's `code` and `status` — is the #22118 block of
+ * `packages/metadata-protocol/src/protocol.runtime-authoring-gate.test.ts`.
+ */
+import { describe, expect, it } from 'vitest';
+import type { AuthoringFinding } from './authoring-rules.js';
+import {
+  buildRuntimeWriteSnapshotSet,
+  buildRuntimeWriteSnapshots,
+  isLocatedOnAnotherEntry,
+  runRuntimeAuthoringRules,
+  runtimeAuthoringRulesFor,
+} from './runtime-gate.js';
+
+type Fields = Record<string, Record<string, unknown>>;
+
+/** The master. `sharingModel` keeps `security-owd-unset` quiet on every fixture here. */
+const master = (fields: Fields = {}, over: Record<string, unknown> = {}) => ({
+  name: 'fx_master',
+  label: 'Master',
+  sharingModel: 'private',
+  fields: {
+    name: { type: 'text', label: 'Name' },
+    code: { type: 'text', label: 'Code' },
+    status: { type: 'text', label: 'Status' },
+    acct: { type: 'lookup', label: 'Account', reference: 'fx_account' },
+    ...fields,
+  },
+  ...over,
+});
+
+/** The master as the author re-saves it: only its label changed. */
+const relabelled = (stored: ReturnType<typeof master>) => ({ ...stored, label: 'Master (renamed)' });
+
+/** The master without one of its fields. */
+const without = (stored: ReturnType<typeof master>, field: string) => {
+  const fields = { ...stored.fields } as Fields;
+  delete fields[field];
+  return { ...stored, label: 'Master (renamed)', fields };
+};
+
+const account = {
+  name: 'fx_account',
+  label: 'Account',
+  sharingModel: 'private',
+  fields: { name: { type: 'text', label: 'Name' } },
+};
+
+/** Measured case 1: a lookup into the master whose picker names `columns`. */
+const pickerDetail = (columns: string[]) => ({
+  name: 'fx_detail2',
+  label: 'Picker Detail',
+  sharingModel: 'private',
+  fields: { m: { type: 'lookup', label: 'Master', reference: 'fx_master', lookupColumns: columns } },
+});
+
+/** Measured case 2: a detail (one `master_detail`) whose `readonlyWhen` reads through `parent`. */
+const parentDetail = (predicate: string) => ({
+  name: 'fx_detail',
+  label: 'Parent Detail',
+  sharingModel: 'private',
+  fields: {
+    hdr: { type: 'master_detail', label: 'Header', reference: 'fx_master' },
+    qty: { type: 'number', label: 'Quantity', readonlyWhen: predicate },
+  },
+});
+
+const gateObject = (item: unknown, objects: unknown[]) =>
+  runRuntimeAuthoringRules({ type: 'object', item, context: { objects } });
+
+/** The door's own rules run over ONE snapshot — what that snapshot holds, not a verdict. */
+const findingsIn = (stack: Record<string, unknown>, type = 'object'): AuthoringFinding[] =>
+  runtimeAuthoringRulesFor(type).flatMap((r) => r.run(stack, { runtimeWriteType: type }));
+
+const dump = (r: unknown) => JSON.stringify(r, null, 2);
+
+/** The two measured cases: the stored detail, and the finding it carries. */
+const MEASURED = [
+  {
+    label: 'an unknown `lookupColumns` entry on a detail',
+    detail: pickerDetail(['nope_col']),
+    rule: 'object-field-ref-unknown',
+    rawPath: 'objects[1].fields.m.lookupColumns[0]',
+  },
+  {
+    label: 'a `readonlyWhen` read through `parent`',
+    detail: parentDetail("parent.acct.name == 'x'"),
+    rule: 'expression-invalid',
+    rawPath: "object 'fx_detail' · field 'qty' readonlyWhen",
+  },
+] as const;
+
+describe('#22118 — a label-only master save is not charged with a stored detail\'s finding', () => {
+  for (const { label, detail, rule, rawPath } of MEASURED) {
+    it(`⭐ RESOLVES — ${label}`, () => {
+      const stored = [master(), account, detail];
+      const snapshots = buildRuntimeWriteSnapshotSet({
+        type: 'object',
+        item: relabelled(master()),
+        context: { objects: stored },
+      })!;
+
+      // Non-vacuous: the detail's finding is NEW against the universe without
+      // the master — the state that answered 422 — and the stored universe
+      // already holds it, at the same raw path.
+      const at = (stack: Record<string, unknown>) =>
+        findingsIn(stack).filter((f) => f.rule === rule && f.path === rawPath);
+      expect(at(snapshots.baseline), dump(findingsIn(snapshots.baseline))).toEqual([]);
+      expect(at(snapshots.candidate), dump(findingsIn(snapshots.candidate))).toHaveLength(1);
+      expect(at(snapshots.stored!), dump(findingsIn(snapshots.stored!))).toHaveLength(1);
+
+      const result = gateObject(relabelled(master()), stored);
+
+      expect(result.rulesRun.length).toBeGreaterThan(0);
+      expect(result.errors, dump(result)).toEqual([]);
+      expect(result.advisories, dump(result)).toEqual([]);
+    });
+  }
+});
+
+describe('#22118 — the controls: what the write changes is still the write\'s', () => {
+  it('⭐ CONTROL — a write that newly breaks a sibling is still REFUSED (positional path)', () => {
+    // The stored master has `code`, so the stored universe holds no finding;
+    // the write removes it, so the picker column now names nothing.
+    const result = gateObject(without(master(), 'code'), [master(), account, pickerDetail(['code'])]);
+
+    expect(result.errors, dump(result)).toEqual([
+      expect.objectContaining({
+        severity: 'error',
+        rule: 'object-field-ref-unknown',
+        path: 'objects.fx_detail2.fields.m.lookupColumns[0]',
+      }),
+    ]);
+    expect(result.errors[0]!.message).toContain('"code" is not a field on object "fx_master"');
+  });
+
+  it('⭐ CONTROL — a write that newly breaks a sibling is still REFUSED (an object named in prose)', () => {
+    // The stored master's `status` is text, so `parent.status.name` traverses
+    // nothing; the write turns it into a lookup, and the detail's predicate
+    // now reads through a reference field.
+    const before = master();
+    const after = master({ status: { type: 'lookup', label: 'Status', reference: 'fx_account' } }, { label: 'Master (renamed)' });
+    const result = gateObject(after, [before, account, parentDetail("parent.status.name == 'x'")]);
+
+    const where = "object 'fx_detail' · field 'qty' readonlyWhen";
+    expect(result.errors, dump(result)).toEqual([
+      expect.objectContaining({ severity: 'error', rule: 'expression-invalid', where, path: where }),
+    ]);
+    expect(result.errors[0]!.message).toContain('through `parent.status`');
+  });
+
+  // The written object's own finding, carried identically by its stored self:
+  // one body per path spelling the location reader reads, so each arm's
+  // written-item answer is exercised through the gate.
+  const OWN = [
+    {
+      spelling: 'positional',
+      fields: { acct: { type: 'lookup', label: 'Account', reference: 'fx_account', lookupColumns: ['nope'] } },
+      over: {},
+      rule: 'object-field-ref-unknown',
+      path: 'objects.fx_master.fields.acct.lookupColumns[0]',
+    },
+    {
+      spelling: 'name-keyed',
+      fields: {},
+      over: { validations: [{ name: 'code_shape', type: 'format', field: 'code', regex: '(', message: 'Bad code' }] },
+      rule: 'validation-rule-regex-uncompilable',
+      path: 'objects.fx_master.validations.code_shape.regex',
+    },
+    {
+      spelling: 'an object named in prose',
+      fields: { code: { type: 'text', label: 'Code', readonlyWhen: "record.acct.name == 'x'" } },
+      over: {},
+      rule: 'expression-invalid',
+      path: "object 'fx_master' · field 'code' readonlyWhen",
+    },
+  ] as const;
+
+  for (const { spelling, fields, over, rule, path } of OWN) {
+    it(`⭐ CONTROL — a finding on the written object itself is still REFUSED, though its stored self carries it (${spelling})`, () => {
+      const stored = master(fields as Fields, over);
+      // Non-vacuous: the stored self carries the identical finding, so a
+      // baseline that let it cancel would wave this write through.
+      const snapshots = buildRuntimeWriteSnapshotSet({
+        type: 'object',
+        item: relabelled(stored),
+        context: { objects: [stored, account] },
+      })!;
+      expect(findingsIn(snapshots.stored!).filter((f) => f.rule === rule).length).toBeGreaterThan(0);
+
+      const result = gateObject(relabelled(stored), [stored, account]);
+
+      expect(result.errors, dump(result)).toEqual([expect.objectContaining({ severity: 'error', rule, path })]);
+    });
+  }
+
+  it('a CREATE is judged as before: no stored self, so the stored universe is the baseline', () => {
+    // Creating the master makes the stored detail's picker column judgeable;
+    // the stored universe never held that finding, so it is this write's.
+    const snapshots = buildRuntimeWriteSnapshotSet({
+      type: 'object',
+      item: master(),
+      context: { objects: [account, pickerDetail(['nope_col'])] },
+    })!;
+    expect(snapshots.stored).toBeUndefined();
+
+    const result = gateObject(master(), [account, pickerDetail(['nope_col'])]);
+
+    expect(result.errors, dump(result)).toEqual([
+      expect.objectContaining({ rule: 'object-field-ref-unknown', path: 'objects.fx_detail2.fields.m.lookupColumns[0]' }),
+    ]);
+  });
+});
+
+describe('#22118 — the same differential on a PERMISSION write', () => {
+  // `security-master-detail-ungranted` is silent while the stack authors no
+  // permission set at all, so with the tenant's only set dropped from the
+  // baseline every ungranted detail read as this write's advisory.
+  const objects = [
+    master(),
+    {
+      name: 'fx_line',
+      label: 'Line',
+      sharingModel: 'controlled_by_parent',
+      fields: { hdr: { type: 'master_detail', label: 'Header', reference: 'fx_master', required: true } },
+    },
+  ];
+  const set = { name: 'fx_ops', label: 'Ops', objects: { fx_master: { allowRead: true, readScope: 'org' } } };
+  const gatePermission = (permissions: unknown[]) =>
+    runRuntimeAuthoringRules({ type: 'permission', item: { ...set, label: 'Ops (renamed)' }, context: { objects, permissions } });
+
+  it('a label-only re-save of the only set carries no stored detail\'s advisory', () => {
+    const result = gatePermission([set]);
+
+    expect(result.rulesRun).toContain('validateSecurityPosture');
+    expect(result.errors, dump(result)).toEqual([]);
+    expect(result.advisories, dump(result)).toEqual([]);
+  });
+
+  it('CONTROL — creating that set still reports it: the stored universe never held the finding', () => {
+    const result = gatePermission([]);
+
+    expect(result.advisories, dump(result)).toEqual([
+      expect.objectContaining({ rule: 'security-master-detail-ungranted', path: 'objects.fx_line.fields.hdr' }),
+    ]);
+  });
+});
+
+describe('#22118 — the snapshot shape', () => {
+  it('`stored` puts the stored self at the slot the item takes in the candidate; siblings keep theirs', () => {
+    const stored = master();
+    const s = buildRuntimeWriteSnapshotSet({
+      type: 'object',
+      item: relabelled(stored),
+      context: { objects: [stored, account, pickerDetail([])] },
+    })!;
+    const names = (stack: Record<string, unknown>) => (stack.objects as { name: string }[]).map((o) => o.name);
+
+    expect(names(s.baseline)).toEqual(['fx_account', 'fx_detail2']);
+    expect(names(s.candidate)).toEqual(['fx_account', 'fx_detail2', 'fx_master']);
+    expect(names(s.stored!)).toEqual(['fx_account', 'fx_detail2', 'fx_master']);
+    expect((s.stored!.objects as unknown[])[2]).toBe(stored);
+    expect((s.candidate.objects as { label: string }[])[2]!.label).toBe('Master (renamed)');
+  });
+
+  it('the published builder still returns exactly its baseline/candidate pair — `stored` is the gate\'s own', () => {
+    const args = { type: 'object', item: relabelled(master()), context: { objects: [master(), account] } };
+    const published = buildRuntimeWriteSnapshots(args)!;
+    const set = buildRuntimeWriteSnapshotSet(args)!;
+
+    expect(Object.keys(published)).toEqual(['baseline', 'candidate']);
+    expect(set.stored).toBeDefined();
+    expect(published.baseline).toEqual(set.baseline);
+    expect(published.candidate).toEqual(set.candidate);
+  });
+
+  it('`stored` is absent for a write whose type is not a context collection', () => {
+    const s = buildRuntimeWriteSnapshotSet({
+      type: 'flow',
+      item: { name: 'f1' },
+      context: { objects: [master()] },
+    })!;
+    expect(s.stored).toBeUndefined();
+  });
+});
+
+describe('#22118 — `isLocatedOnAnotherEntry` reads the location off the path spelling', () => {
+  const snapshot = { objects: [{}, {}, {}], permissions: [{}], books: [], datasets: [] };
+  const located = { snapshot, stackKey: 'objects', itemName: 'fx_master', writtenSlot: 2 };
+
+  const CASES: ReadonlyArray<readonly [string, boolean]> = [
+    // positional
+    ['objects[2].fields.acct.lookupColumns[0]', false],
+    ['objects[1].fields.m.lookupColumns[0]', true],
+    ['permissions[0].objects.fx_master.readScope', true],
+    // name-keyed
+    ['objects.fx_master.validations.v.regex', false],
+    ['objects.fx_detail.validations.v.regex', true],
+    // an object named in prose
+    ["object 'fx_master' · field 'code' readonlyWhen", false],
+    ["object 'fx_detail' · field 'qty' readonlyWhen", true],
+    // NOT positively located: today's verdict, never a cancellation
+    ['flows[0].nodes[1].config', false],
+    ['packages/lint/src/validate-expressions.ts', false],
+    ['object "fx_detail" › fields.m', false],
+    ["flow 'f1' · node 'n1'", false],
+    ['', false],
+  ];
+
+  for (const [path, another] of CASES) {
+    it(`${JSON.stringify(path)} → ${another}`, () => {
+      expect(isLocatedOnAnotherEntry(path, located)).toBe(another);
+    });
+  }
+});