Testing component with query param

[SangeetAgarwal]

I'm a bit stumped, I did try googling + stackoverflow but can't seem to find a way to test my component with a query param.

If I have the following

       [Parameter]
        [SupplyParameterFromQuery(Name = "discount")]
        public string Discount { get; set; }

then I can always have
var cut = RenderComponent<Hug>(r => r.Add(k => k.Discount, "discount"));

But, if my code looks like so

    protected override void OnInitialized()
        {
            var uri = Navigation.ToAbsoluteUri(Navigation.Uri);
            QueryHelpers.ParseQuery(uri.Query).TryGetValue("discount", out var discount);
            InputInvoiceContact = new InputInvoiceContact { Coupon = discount };

            EditContext = new EditContext(InputInvoiceContact);
        }

Then I'm not quite sure how to pass the discount query param for testing.

[egil]

The code you have in OnInitialized is not needed if you are using the SupplyParameterFromQuery attribute. The attribute essentially does what you have in OnInitialized for you.

That said, you need to set the current url via the fake navigation manager that is part of bUnit before rendering your component. If you do that, the code in OnInitialized will work.

Learn more here: https://bunit.dev/docs/test-doubles/fake-navigation-manager

[SangeetAgarwal]

The code you have in OnInitialized is not needed if you are using the SupplyParameterFromQuery attribute. The attribute essentially does what you have in OnInitialized for you.

I know, I was showing two different ways, the one you see in the OnInitialized is how I have it.

Though there is a subtle difference between the two approaches.

What I have in the OnInitialized i.e. QueryHelpers.ParseQuery(uri.Query).TryGetValue("discount", out var discount); returns stringValues. So, if I have ?discount=govdiscount&discount=anotherdiscount then I would get two values govdiscount and anotherdiscount where as with [SupplyParameterFromQuery(Name = "discount")], I'll only get anotherdiscount.

you need to set the current url via the fake navigation manager that is part of bUnit before rendering your component.

Thanks for letting me know. Taking a look at that.

[egil]

What I have in the OnInitialized i.e. QueryHelpers.ParseQuery(uri.Query).TryGetValue("discount", out var discount); returns stringValues. So, if I have ?discount=govdiscount&discount=anotherdiscount then I would get two values govdiscount and anotherdiscount where as with [SupplyParameterFromQuery(Name = "discount")], I'll only get anotherdiscount.

I think that is how blazor works and not related to bUnit.

I guess if you want both query string parameters you need to use the navigation manager approach.

To test that, look at the fake navigation manager docs page. That should get you there.