fix(core): admit list items under per-item text quotas

packages/mayfly/src/core/ui-validator.ts

@@ -253,7 +253,11 @@ function field(value: unknown, path: string, state: ValidationState): MayflyFiel
   }))
 }
 
-function listItem(value: unknown, path: string, state: ValidationState): MayflyListItem {
+function listItem(value: unknown, path: string): MayflyListItem {
+  // Item collections are unbounded data rows: each admits under its own
+  // quota — the same isolation lazy list admission already applies — so the
+  // aggregate row text of a large picker cannot exhaust the tree budget.
+  const state = validationState()
   return enter(value, path, state, object => {
     const disabledValue = own(object, 'disabled', path)
     const detailSpansValue = own(object, 'detailSpans', path)
@@ -461,7 +465,7 @@ function lazyListItems(value: unknown, path: string): readonly MayflyListItem[]
       }
       let admitted: MayflyListItem
       try {
-        admitted = listItem(raw(index), `${path}[${String(index)}]`, validationState())
+        admitted = listItem(raw(index), `${path}[${String(index)}]`)
         const owner = owners.get(admitted.id)
         if (owner !== undefined && owner !== index) invalid(`${path} contains duplicate ids`)
         owners.set(admitted.id, index)
@@ -754,7 +758,7 @@ function formField(value: unknown, path: string, state: ValidationState): Mayfly
     }
     if (kind === 'select' || kind === 'multiselect') {
       const raw = required(object, 'value', path)
-      const options = collection(required(object, 'options', path), `${path}.options`).map((item, index) => listItem(item, `${path}.options[${String(index)}]`, state))
+      const options = collection(required(object, 'options', path), `${path}.options`).map((item, index) => listItem(item, `${path}.options[${String(index)}]`))
       uniqueIds(options, `${path}.options`)
       if (kind === 'multiselect') return { kind, ...common, value: parseValue(raw, `${path}.value`) as readonly string[], options, ...selectionBounds(object, path) }
       if (raw !== null && typeof raw !== 'string') invalid(`${path}.value must be a string or null`)
@@ -906,7 +910,7 @@ function node(value: unknown, path: string, state: ValidationState, depth: numbe
           : 0
         const items = itemCount > MAYFLY_UI_MAX_COLLECTION
           ? lazyListItems(itemsValue, `${path}.items`)
-          : collection(itemsValue, `${path}.items`).map((item, index) => listItem(item, `${path}.items[${String(index)}]`, state))
+          : collection(itemsValue, `${path}.items`).map((item, index) => listItem(item, `${path}.items[${String(index)}]`))
         if (itemCount <= MAYFLY_UI_MAX_COLLECTION) uniqueIds(items, `${path}.items`)
         const selectedIds = collection(required(object, 'selectedIds', path), `${path}.selectedIds`).map((item, index) => text(item, `${path}.selectedIds[${String(index)}]`, state))
         if (new Set(selectedIds).size !== selectedIds.length) invalid(`${path}.selectedIds contains duplicate ids`)

packages/mayfly/tests/core/ui-validator.spec.ts

@@ -217,6 +217,25 @@ describe('validateMayflyUiNode', () => {
     expect(result.value.items[0]).toMatchObject({ id: '0' })
   })
 
+  it('bounds each admitted list item and select option by its own text quota', () => {
+    const row = (index: number) => ({
+      id: `session-${String(index)}`,
+      label: `Session title ${String(index)}`,
+      detail: 'd'.repeat(80),
+      searchText: 's'.repeat(80),
+    })
+    // 120 rows × ~190 chars ≈ 23k aggregate — over the shared tree budget but
+    // each item far under it; per-item quotas admit the picker (the /sessions
+    // regression: a populated directory rejected its own session list).
+    const items = Array.from({ length: 120 }, (_, index) => row(index))
+    expect(validateMayflyUiNode(ui.list({ role: 'choose', id: 'sessions', selectedIds: [], items })).ok).toBe(true)
+    const options = Array.from({ length: 120 }, (_, index) => row(index))
+    expect(validateMayflyUiNode({ kind: 'form', id: 'f', fields: [{ kind: 'select', id: 's', label: 'S', value: null, options }] }).ok).toBe(true)
+    // The per-item quota still applies to the item itself.
+    const oversized = [{ id: 'a', label: 'A'.repeat(MAYFLY_UI_MAX_TEXT + 1) }]
+    expect(validateMayflyUiNode(ui.list({ role: 'choose', id: 'x', selectedIds: [], items: oversized }))).toMatchObject({ ok: false, code: 'MAYFLY_LIMIT_EXCEEDED' })
+  })
+
   it('contains sparse, accessor, throwing, and subclassed large list inputs', () => {
     const sparse = Array.from({ length: 201 }, (_, index) => ({ id: String(index), label: 'ok' }))
     delete sparse[200]