Add excepion test case for GetAll in tags service tests

Author: lakatoshv

BlogWebApp/Tests/Blog.ServicesTests/EntityServices/TagsServiceTests.cs

@@ -147,6 +147,20 @@ public void GetAll_WhenTagsDoesNotExists_ShouldReturnNothing()
     }
 
     /// <summary>
+    /// Get all tags.
+    /// Should throw exception when repository throws exception.
+    /// </summary>
+    [Fact]
+    public void GetAll_WhenRepositoryThrowsException_ShouldThrowException()
+    {
+        //Arrange
+        _tagsRepositoryMock.Setup(x => x.GetAll())
+            .Throws(() => new Exception("Test exception"));
+
+        //Assert
+        Assert.Throws<Exception>(() => _tagsService.GetAll());
+    }
+
     #endregion
 
     #region Get All Async function