fix(plugin-grid): retire the three inert fieldMeta copies the cell never reads

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

.changeset/7166-retire-inert-fieldmeta-copies.md

@@ -0,0 +1,56 @@
+---
+'@object-ui/plugin-grid': patch
+---
+
+`ObjectGrid` no longer copies `descriptionField`, `lookupColumns` or `lookupFilters` onto a
+relational column's `fieldMeta` (objectui#7166). No behaviour change — all three still reach
+the inline lookup picker, by a different seam.
+
+`applyRelationalMeta` writes the copy set onto the `fieldMeta` that `generateColumns` hands
+to `<CellRenderer>` as the `field` prop — six JSX passes across the three column-building
+paths, and nowhere else. For a relational column that resolves to `LookupCellRenderer`,
+which reads exactly `reference_to`, `reference`, `display_field`, `displayField`,
+`reference_field` and `options`; a `user` column resolves to `UserCellRenderer`, which
+destructures `{ value }` and reads no field meta at all. Measured by receiver rather than by
+count: `packages/fields/src/index.tsx`, the file holding **every** cell renderer, contains
+**zero** occurrences of the three retired keys, against a control of 22 occurrences of the
+`display_field` / `displayField` / `reference_to` spellings the cell does read.
+
+Their only readers off a field meta are `LookupField` and `UserField` — the two **editor**
+widgets — and the grid's inline editor does not receive this bag. `renderCellEditor` looks
+the field up in the object schema and spreads the whole def into the widget
+(`{ name: ctx.column.accessorKey, ...fieldDef }`), so every key a def carries reaches
+`LookupField` whether or not it is copied. The copies were dead writes: the objectui#6711
+(`reference_to_field`) and objectui#6874 (`titleFormat`) class, arriving from the opposite
+direction — those keys had no *declaration*, these have no *reader on this path*.
+
+Two of the three, `descriptionField` and `lookupColumns`, were **added** by objectui#6875 as
+its fix, classified from a read-set derivation alone. Its third key, `displayField`, is
+genuinely delivered and stays copied — and it is the one that arrived with a rendering test.
+⭐ The generalisable lesson, now recorded in both docblocks: **a derivation establishes that
+a consumer READS a key; it does not establish that a given BAG is how the consumer gets it.**
+
+- New `__tests__/relationalMetaCopySet-7166.test.tsx` renders both directions. The **cell**:
+ four lookup columns over one referenced record, differing only in the key under test, all
+ resolve the same text, while the `displayField` control column resolves something else —
+ the control is what makes the three zeros readings rather than a fixture that never reached
+ the lookup path. The **editor**: each retired key still takes effect in the inline picker
+ with the copy set no longer carrying it — `descriptionField` drives the secondary line,
+ `lookupColumns` shapes the picker columns, `lookupFilters` scopes the candidates — each
+ against a sibling control column that declares nothing.
+- The three snake_case `legacy-alias` spellings — `description_field`, `lookup_filters`,
+ `id_field` — have the same reader-side verdict and are **deliberately kept**. They are
+ recorded as legacy aliases precisely because a host `DataSource` outside these repos may
+ hand-feed them; that is a producer-side argument, untouched by this reader-side
+ measurement. Their verdict is now recorded on the table with the open producer question
+ stated, so the next pass inherits a measurement instead of a silence.
+- ⛔ The derivation gate cannot enforce this retirement, and now says so. Its read set is a
+ union over three consumers, two of which are not fed this bag, so all three retired keys
+ remain in it and every derived assertion passes whichever verdict they carry. Their absence
+ is pinned by an explicit hand-written assertion plus the rendering test. Re-scoping the
+ derivation around the cell alone is a design change to objectui#6875's mechanism and is
+ filed, not made here.
+- The gate is strengthened, not weakened: every `deferred` verdict is now mechanically proved
+ spec-declared against the installed `FieldSchema`, and the sibling pins
+ (`relationalMetaCopySet-6711` / `-6874`) turn the retired `lookupFilters` into a live
+ negative assertion on a fixture that still declares it.

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6711.test.tsx

@@ -68,11 +68,11 @@ const MANAGER_DEF = {
  reference_to_field: 'MUST_NOT_BE_COPIED',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -161,13 +161,18 @@ describe('objectui#6711 — ObjectGrid no longer copies `reference_to_field` ont
  expect(meta).not.toHaveProperty('reference_to_field');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });

packages/plugin-grid/src/__tests__/relationalMetaCopySet-6874.test.tsx

@@ -79,11 +79,11 @@ const MANAGER_DEF = {
  reference_to_field: 'x',
 };
 
-/** The seven keys that survive both retirements — the control. */
+/** The six keys that survive every retirement so far — the control. */
 const SURVIVING_KEYS = [
  'reference_to', 'reference',
  'display_field', 'id_field', 'description_field',
- 'lookup_filters', 'lookupFilters',
+ 'lookup_filters',
 ] as const;
 
 const ROWS = [{ id: 'r1', name: 'Tower T1', manager: 'u1' }];
@@ -172,13 +172,18 @@ describe('objectui#6874 — ObjectGrid no longer copies `titleFormat` onto field
  expect(meta).not.toHaveProperty('titleFormat');
  });
 
- it(`still copies the seven surviving relational keys (${name})`, async () => {
+ it(`still copies the six surviving relational keys (${name})`, async () => {
  const meta = await renderAndCaptureMeta(schemaExtra);
  for (const key of SURVIVING_KEYS) {
  expect(meta).toHaveProperty(key);
  }
  expect(meta.reference_to).toBe('users');
  expect(meta.display_field).toBe('name');
+ // objectui#7166 retired `lookupFilters` from the copy set — its only
+ // reader is an editor widget, which `renderCellEditor` feeds from the
+ // schema def. The fixture above still declares it, so this absence is a
+ // reading and not a fixture that never offered the key.
+ expect(meta).not.toHaveProperty('lookupFilters');
  });
  }
 });