support for non-latin characters in search

src/adverts/filters/advert-filter-predicate.spec.ts

@@ -133,4 +133,19 @@ describe('createAdvertFilterPredicate', () => {
       .map(({id}) => id))
       .toMatchObject(['advert-30'])
   })  
+
+  it('bugfix: supports exotic characters', () => {
+    const p = createAdvertFilterPredicate(createTestUser(), {search: 'ÅÄÖ'})
+
+    const adverts = createSampleAdverts(100, {
+      'advert-10': {title: 'I like my unicorn named åäö!'},
+      'advert-20': {description: ' UniCorns are the best in the whole wåäörld'}
+    });
+
+    expect(
+      adverts.filter(p)
+      .map(({id}) => id))
+      .toMatchObject(['advert-10', 'advert-20'])
+  })
+
 })

src/adverts/filters/advert-filter-predicate.ts

@@ -9,7 +9,8 @@ const regexpEscape = (s: string): string => s.replace(/[|\\{}()[\]^$+*?.]/g, '\\
 const createFreeTextPredicate = (search: string): Predicate<Advert> => {
   // extract individual words from search
 
-  const matchers = ((search||'').match(/(\w+)/g) || [])
+  // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_expressions/Character_classes#looking_for_a_word_from_unicode_characters
+  const matchers = ((search||'').match(/([\u0000-\u0019\u0021-\uFFFF]+)/gm) || [])
     .filter(v => v)
     .filter(v => v.length >= 3)
     .map(regexpEscape)