Blazor doesn't create component and create element instead

[max-meng1]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

I just came across this weird issue, that I havn't seen this before.

<div class="lv-media-viewer-wrapper">
    <VideoMediaViewer Media="Media"
                      Size="Size"
                      OnNext="OnNext"
                      Loading="OnViewerLoading"
                      Loaded="OnViewerLoaded"
                      Stopped="Stopped"
                      AutoPlay="@AutoPlay"
                      StatusChanged="StatusChanged" />
</div>

The above Razor content doesn't render properly, and generates a plain HTML tag instead:

<div class="lv-media-viewer-wrapper">
<videomediaviewer media="Media" size="Size" onnext="OnNext" loading="OnViewerLoading" loaded="OnViewerLoaded" stopped="Stopped" statuschanged="StatusChanged"></videomediaviewer>
</div>

VideoMediaViewer, and it's parent component are in same namespace. I also checked compiled code, other components are
recognized (using OpenComponent)

TypeInference.CreateCascadingValue_0<MediaPlayer>(__builder2, 10, 11, this, 12, true, 13, new RenderFragment(this, (RenderTreeBuilder __builder3) => {
                        __builder3.OpenElement(14, "div");
                        __builder3.OpenComponent<LvPanel>(15);
                        __builder3.AddAttribute(16, "Collapsed", RuntimeHelpers.TypeCheck<bool>(true));
                        __builder3.AddAttribute(17, "ChildContent", new RenderFragment(this, (RenderTreeBuilder __builder4) => {
                            __builder4.OpenComponent<RecordingMetaData>(18);
                            __builder4.AddAttribute(19, "Recording", RuntimeHelpers.TypeCheck<Recording>(this.Store.Recording));
                            __builder4.AddAttribute(20, "RecordingDetails", RuntimeHelpers.TypeCheck<RecordingDetails>(this.Store.RecordingDetails));
                            __builder4.CloseComponent();
                        }));
                        __builder3.CloseComponent();
                        __builder3.AddMarkupContent(21, "\r\n                    ");
                        __builder3.OpenElement(22, "div");
                        __builder3.AddAttribute(23, "class", "lv-media-viewer-wrapper");
                        __builder3.OpenElement(24, "VideoMediaViewer");
                        __builder3.AddAttribute(25, "Media", "Media");
                        __builder3.AddAttribute(26, "Size", "Size");
                        __builder3.AddAttribute(27, "OnNext", "OnNext");
                        __builder3.AddAttribute(28, "Loading", "OnViewerLoading");
                        __builder3.AddAttribute(29, "Loaded", "OnViewerLoaded");
                        __builder3.AddAttribute(30, "Stopped", "Stopped");
                        __builder3.AddAttribute(31, "AutoPlay", this.AutoPlay);
                        __builder3.AddAttribute(32, "StatusChanged", "StatusChanged");
                        __builder3.CloseElement();
                        __builder3.CloseElement();
                        __builder3.CloseElement();
                    }));

Expected Behavior

VideoMediaViewer should be rendered as a Blazor component

Steps To Reproduce

No response

Exceptions (if any)

No response

.NET Version

7.0

Anything else?

No response

[Xyncgas]

did you spell your component's filename wrong
I ran into this in the past
(what if you change VideoMediaViewer to another name)

[SteveSandersonMS]

@max-meng1 Does the IDE show <VideoMediaViewer> with the correct syntax highlighting to indicate it is recognized as a known component? If not, there is probably a mistake in the name or namespace, or something less obvious (e.g., an entry in your .csproj explicitly excluding that file from the compilation).

Or, if you are able to reproduce this in a new project, can you post repro steps?

[max-meng1]

@SteveSandersonMS Thanks for the reply, it seems to do with inheriting .razor in same project. I'm pretty sure this used to work.

I have created a repro project
https://github.com/max-meng1/BlazorApp1

To learn more about what this message means, what to expect next, and how this issue will be handled you can read our Triage Process document.
We're moving this issue to the .NET 8 Planning milestone for future evaluation / consideration. Because it's not immediately obvious what is causing this behavior, we would like to keep this around to collect more feedback, which can later help us determine how to handle this. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact work.

[danroth27]

@333fred Looks like this might be related to #8718?

[333fred]

@danroth27 yes, this looks like a dup. Verified that it does not repro on the next servicing release: