Programming exercises: Display error message for unexpected errors on exercise import

src/main/webapp/app/exercises/programming/manage/update/programming-exercise-update.component.ts

@@ -38,6 +38,7 @@ import { ProgrammingExerciseDifficultyComponent } from 'app/exercises/programmin
 import { ProgrammingExerciseLanguageComponent } from 'app/exercises/programming/manage/update/update-components/programming-exercise-language.component';
 import { ProgrammingExerciseGradingComponent } from 'app/exercises/programming/manage/update/update-components/programming-exercise-grading.component';
 import { ExerciseUpdatePlagiarismComponent } from 'app/exercises/shared/plagiarism/exercise-update-plagiarism/exercise-update-plagiarism.component';
+import { scrollToTopOfPage } from 'app/shared/util/utils';
 
 export interface ImportOptions {
     recreateBuildPlans: boolean;
@@ -674,6 +675,8 @@ export class ProgrammingExerciseUpdateComponent implements AfterViewInit, OnDest
     private onSaveError(error: HttpErrorResponse) {
         let errorMessage;
         let disableTranslation;
+        let translationParams;
+
         // Workaround for conflict error, since conflict errors do not have the 'X-artemisApp-alert' header
         if (error.status === 409 && error.error && error.error['X-artemisApp-error'] === 'error.sourceExerciseInconsistent') {
             errorMessage = 'artemisApp.consistencyCheck.error.programmingExerciseImportFailed';
@@ -682,13 +685,22 @@ export class ProgrammingExerciseUpdateComponent implements AfterViewInit, OnDest
             errorMessage = error.headers.get('X-artemisApp-alert')!;
             disableTranslation = true;
         }
+
+        const errorMessageToBeTranslatedNotFound = !errorMessage;
+        if (errorMessageToBeTranslatedNotFound) {
+            errorMessage = `error.unexpectedError`;
+            translationParams = { error: error.statusText };
+            disableTranslation = false;
+        }
+
         this.alertService.addAlert({
             type: AlertType.DANGER,
             message: errorMessage,
+            translationParams: translationParams,
             disableTranslation: disableTranslation,
         });
         this.isSaving = false;
-        window.scrollTo(0, 0);
+        scrollToTopOfPage();
     }
 
     /**

src/test/javascript/spec/component/programming-exercise/programming-exercise-update.component.spec.ts

@@ -246,6 +246,36 @@ describe('ProgrammingExerciseUpdateComponent', () => {
             expect(comp.isSaving).toBeFalse();
             expect(alertSpy).toHaveBeenCalledWith({ type: AlertType.DANGER, message: 'error-message', disableTranslation: true });
         });
+
+        it('should show alert for unknown error', async () => {
+            // GIVEN
+            const entity = new ProgrammingExercise(undefined, undefined);
+            entity.id = 1;
+            jest.spyOn(programmingExerciseService, 'update').mockReturnValue(
+                throwError(
+                    new HttpResponse({
+                        headers: new HttpHeaders(),
+                        status: 500,
+                        statusText: 'Internal Server Error',
+                    }),
+                ),
+            );
+            const alertSpy = jest.spyOn(alertService, 'addAlert');
+            comp.programmingExercise = entity;
+            comp.backupExercise = {} as ProgrammingExercise;
+            comp.programmingExercise.course = course;
+            // WHEN
+            comp.save();
+
+            // THEN
+            expect(comp.isSaving).toBeFalse();
+            expect(alertSpy).toHaveBeenCalledWith({
+                type: AlertType.DANGER,
+                message: 'error.unexpectedError',
+                translationParams: { error: 'Internal Server Error' },
+                disableTranslation: false,
+            });
+        });
     });
 
     describe('exam mode', () => {