Enhancement: ignore diacritics, support multiple substring matching for UI filtering (#13021)

src-ui/src/app/utils/text-search.spec.ts

@@ -0,0 +1,17 @@
+import { matchesSearchText } from './text-search'
+
+describe('text search utilities', () => {
+  it('matches text accent-insensitively', () => {
+    expect(matchesSearchText('R\u00e9sum\u00e9', 'resume')).toBeTruthy()
+    expect(matchesSearchText('S\u00f8ren', 'soren')).toBeTruthy()
+    expect(matchesSearchText('\u0152uvre', 'oeuvre')).toBeTruthy()
+    expect(matchesSearchText('Invoice', 'receipt')).toBeFalsy()
+  })
+
+  it('matches all whitespace-separated search terms independently', () => {
+    expect(matchesSearchText('taxes 2026', 'tax 26')).toBeTruthy()
+    expect(matchesSearchText('2026 taxes', 'tax 26')).toBeTruthy()
+    expect(matchesSearchText('Tax\u00e9s 2026', 'taxe 26')).toBeTruthy()
+    expect(matchesSearchText('taxes 2026', 'tax receipt')).toBeFalsy()
+  })
+})

src-ui/src/app/utils/text-search.ts

@@ -0,0 +1,23 @@
+import { normalizeSync } from 'normalize-diacritics'
+
+export type SearchTextValue =
+  | string
+  | number
+  | boolean
+  | bigint
+  | null
+  | undefined
+
+export function normalizeSearchText(value: SearchTextValue): string {
+  return normalizeSync(String(value ?? '')).toLocaleLowerCase()
+}
+
+export function matchesSearchText(
+  value: SearchTextValue,
+  searchText: SearchTextValue
+): boolean {
+  const normalizedValue = normalizeSearchText(value)
+  const searchTerms = normalizeSearchText(searchText).trim().split(/\s+/)
+
+  return searchTerms.every((term) => normalizedValue.includes(term))
+}