BUGFIX: Reintroduce graceful handling of empty parameter in `translat…

…e()`

the use of

```
i18nRegistry.translate(ui?.help?.message)
```

in

https://github.com/neos/neos-ui/blob/a60961417e7ad49a22b75d48dbe4b2542a25ae5b/packages/neos-ui/src/Containers/Modals/SelectNodeType/nodeTypeItem.js#L60

brings the Ui currently to a fatal crash:

> Message: undefined is not an object (evaluating 'string5.split')

This change reintroduces the old behaviour by returning a possible fallback instead or `undefined`.

packages/neos-ui-i18n/src/registry/I18nRegistry.spec.ts

@@ -111,3 +111,11 @@ test(`
 
     expect(actual).toBe('Singular Translation');
 });
+
+test(`
+    Host > Containers > I18n: Returns undefined if no id is specified`, () => {
+    const registry = new I18nRegistry('');
+    const actual = registry.translate(undefined);
+
+    expect(actual).toBe(undefined);
+});

packages/neos-ui-i18n/src/registry/I18nRegistry.ts

@@ -23,6 +23,11 @@ const errorCache: Record<string, boolean> = {};
  * @deprecated Use `import {translate} from '@neos-project/neos-ui-i18n'` instead
  */
 export class I18nRegistry extends SynchronousRegistry<unknown> {
+    /**
+     * @deprecated Use `import {translate} from '@neos-project/neos-ui-i18n'` instead
+     */
+    translate(emptyAddress: undefined): undefined;
+
     /**
      * Retrieves the translation string that is identified by the given
      * identifier. If it is a fully qualified translation address (a string
@@ -176,13 +181,17 @@ export class I18nRegistry extends SynchronousRegistry<unknown> {
     ): string;
 
     translate(
-        transUnitIdOrFullyQualifiedTranslationAddress: string,
+        transUnitIdOrFullyQualifiedTranslationAddress?: string,
         explicitlyProvidedFallback?: string,
         parameters?: LegacyParameters,
         explicitlyProvidedPackageKey: string = 'Neos.Neos',
         explicitlyProvidedSourceName: string = 'Main',
         quantity: number = 0
     ) {
+        if (typeof transUnitIdOrFullyQualifiedTranslationAddress !== 'string' || transUnitIdOrFullyQualifiedTranslationAddress === '') {
+            // legacy behaviour to guard against undefined
+            return explicitlyProvidedFallback;
+        }
         const fallback = explicitlyProvidedFallback || transUnitIdOrFullyQualifiedTranslationAddress;
         const translationAddress = getTranslationAddress(transUnitIdOrFullyQualifiedTranslationAddress, explicitlyProvidedPackageKey, explicitlyProvidedSourceName);
         const translation = this.getTranslation(translationAddress);