fix: 🐛 pipe return empty string by default (#192)

Author: itayod

projects/ngneat/transloco/src/lib/tests/pipe/pipe.spec.ts

@@ -21,6 +21,11 @@ describe('TranslocoPipe', () => {
     spyOn(pipe as any, 'updateValue').and.callThrough();
   });
 
+  it('should return empty string as default', () => {
+    pipe = new TranslocoPipe(translateServiceMock, null, 'es', cdrMock);
+    expect(pipe.transform('title', {})).toBe('');
+  });
+
   it('should use provided language', fakeAsync(() => {
     spyOn(translateServiceMock, 'translate').and.callThrough();
     pipe = new TranslocoPipe(translateServiceMock, null, 'es', cdrMock);
@@ -55,7 +60,12 @@ describe('TranslocoPipe', () => {
 
   it('should load scope translation with multiple provided scopes', fakeAsync(() => {
     spyOn(translateServiceMock, 'translate').and.callThrough();
-    pipe = new TranslocoPipe(translateServiceMock, [{ scope: 'lazy-page', alias: 'lazyPageAlias' }, { scope: 'admin-page', alias: 'adminPageAlias' }], null, cdrMock);
+    pipe = new TranslocoPipe(
+      translateServiceMock,
+      [{ scope: 'lazy-page', alias: 'lazyPageAlias' }, { scope: 'admin-page', alias: 'adminPageAlias' }],
+      null,
+      cdrMock
+    );
     (pipe as any).listenToLangChange = true;
     pipe.transform('lazyPageAlias.title', {});
     runLoader();

projects/ngneat/transloco/src/lib/transloco.pipe.ts

@@ -15,7 +15,7 @@ import { ScopeResolver } from './scope-resolver';
 })
 export class TranslocoPipe implements PipeTransform, OnDestroy {
   private subscription: Subscription | null = null;
-  private lastValue: string | undefined;
+  private lastValue: string = '';
   private lastKey: string | undefined;
   private listenToLangChange: boolean;
   private path: string;
@@ -54,8 +54,10 @@ export class TranslocoPipe implements PipeTransform, OnDestroy {
             active: activeLang
           });
 
-          return Array.isArray(this.providerScope) ?
-            forkJoin((<TranslocoScope[]>this.providerScope).map(providerScope => this.resolveScope(lang, providerScope)))
+          return Array.isArray(this.providerScope)
+            ? forkJoin(
+                (<TranslocoScope[]>this.providerScope).map(providerScope => this.resolveScope(lang, providerScope))
+              )
             : this.resolveScope(lang, this.providerScope);
         }),
         listenOrNotOperator(this.listenToLangChange)
@@ -76,9 +78,9 @@ export class TranslocoPipe implements PipeTransform, OnDestroy {
   }
 
   private resolveScope(lang: string, providerScope: TranslocoScope): Observable<Translation | Translation[]> {
-      let resolvedScope = this.scopeResolver.resolve({ inline: undefined, provider: providerScope });
-      this.path = this.langResolver.resolveLangPath(lang, resolvedScope);
-      const inlineLoader = resolveInlineLoader(providerScope, resolvedScope);
-      return this.translocoService._loadDependencies(this.path, inlineLoader);
+    let resolvedScope = this.scopeResolver.resolve({ inline: undefined, provider: providerScope });
+    this.path = this.langResolver.resolveLangPath(lang, resolvedScope);
+    const inlineLoader = resolveInlineLoader(providerScope, resolvedScope);
+    return this.translocoService._loadDependencies(this.path, inlineLoader);
   }
 }

src/assets/i18n/inline/en.json

@@ -0,0 +1,3 @@
+{
+  "title": "Inline Loaders English"
+}

src/assets/i18n/inline/es.json

@@ -0,0 +1,3 @@
+{
+  "title": "Inline Loaders Spanish"
+}