feat: add formatDisplayNames and formatList methods

src/formatters/values_formatter.ts

@@ -191,4 +191,18 @@ export class Formatter {
   formatPlural(value: string | number, options?: Intl.PluralRulesOptions): string {
     return formatters.plural(this.locale, options).select(Number(value))
   }
+
+  /**
+   * Format an array of strings to a sentence.
+   */
+  formatList(list: Iterable<string>, options?: Intl.ListFormatOptions) {
+    return formatters.list(this.locale, options).format(list)
+  }
+
+  /**
+   * Format region, currency, language codes to their display names
+   */
+  formatDisplayNames(code: string, options: Intl.DisplayNamesOptions) {
+    return formatters.displayNames(this.locale, options).of(code)
+  }
 }

tests/values_formatter.spec.ts

@@ -158,4 +158,18 @@ test.group('Formatter', () => {
     const formatter = new Formatter('en-in')
     assert.equal(formatter.formatPlural(3, { type: 'ordinal' }), 'few')
   })
+
+  test('format a list', ({ assert }) => {
+    const formatter = new Formatter('en-in')
+    assert.equal(
+      formatter.formatList(['Me', 'myself', 'I'], { type: 'conjunction' }),
+      'Me, myself and I'
+    )
+  })
+
+  test('format display names', ({ assert }) => {
+    const formatter = new Formatter('en-in')
+    assert.equal(formatter.formatDisplayNames('INR', { type: 'currency' }), 'Indian Rupee')
+    assert.equal(formatter.formatDisplayNames('en-US', { type: 'language' }), 'American English')
+  })
 })