Automatic code fixes unavailable for BL0015 in components and BL0016 in all project types (.NET 11)

[VigneshwaranGovindharajan]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

The JavaScript interop analyzer provides automatic code fixes for certain warnings, but the availability is inconsistent and limited:

BL0015 ("Make [JSInvokable] method public"):

• Code fix IS available in Razor Class Library (.cs class files)
• Code fix IS NOT available in Razor component (.razor) files in Server and Client projects
• Developers using .razor components must manually edit code, while RCL developers get automatic fixes for the same warning

BL0016 ("Guard JavaScript interop calls"):

• Code fix is NOT available in any project type (Server, Client, or RCL)
• Developers must manually add try/catch blocks or restructure code to move calls to OnAfterRender

This creates a poor developer experience: the analyzer identifies the problem but provides no automated solution in most scenarios.

Expected Behavior

• BL0015 code fix should work in .razor component files (Razor components in Server and Client projects), just as it does in RCL files
• BL0016 code fix should be available (the IDE should provide a suggestion for wrapping in try/catch)

At the very least, both warnings should offer consistent code fix availability across all project types.

Steps To Reproduce

Steps To Reproduce

1. Create a Blazor Web App targeting .NET 11 with Interactive Server render mode
2. In a .razor component file, create a private method with [JSInvokable] attribute:

[JSInvokable]
private async Task MyPrivateMethod()
{
    // Code here
}

3. Build the project - BL0015 warning appears
4. In Visual Studio, click on the warning and look for Quick Actions (Alt+.)
5. Observe: No automatic code fix is offered

Contrast with RCL:

1. Create the same private [JSInvokable] method in an RCL .cs class file
2. Build - BL0015 warning appears
3. In Visual Studio, click on the warning and look for Quick Actions (Alt+.)
4. Observe: "Make [JSInvokable] method public" code fix IS available

Exceptions (if any)

No exceptions are thrown. The issue is purely about missing IDE code fix support.

.NET Version

11.0.100-preview.7.26381.103

Anything else?

Test Environments:

• Visual Studio 2022 (latest)
• Windows 11
• .NET 11 Preview 7

Affected Code Patterns:

Warning	Project Type	Code Fix	Impact
BL0015	RCL (.cs class)	✓ Available	Automatic fix works
BL0015	Server (.razor)	✗ Not Available	Manual fix required
BL0015	Client (.razor)	✗ Not Available	Manual fix required
BL0016	All projects	✗ Not Available	Manual fix required

Reproduction Repository:

• Sample App: validation-68483-javascript-interop
• Test Results: Full Validation Report

Additional Context

The inconsistency between RCL and component code fixes creates developer confusion. Developers expect that if a warning exists in the IDE, there should be a way to fix it automatically. When fixes work in one project type but not another for the same warning, it feels like a gap in the analyzer implementation.

For BL0016, having no code fix at all means developers must learn the correct pattern from documentation rather than getting guidance from the IDE when they violate it. An automatic suggestion to wrap calls in try/catch would improve the developer experience significantly.

[github-actions]

Triage Summary

Area: area-blazor (JS interop analyzer/code-fix behavior for [JSInvokable] and JS interop guard diagnostics)
Type: Bug (BL0015 code fix works in RCL .cs files but not in .razor components; BL0016 has no code fix in any project type)

Potential Duplicates

• [Validation] Analyzer diagnostics for JavaScript interop #68483 - [Validation] Analyzer diagnostics for JavaScript interop (related validation-scenario tracking issue for the same BL00xx diagnostics, not a duplicate report)

Notes

• Missing from the report: repro steps do not include the exact BL0016 scenario code (only BL0015); a minimal repro for BL0016's missing code fix would help confirm scope.

Generated by Issue Triage Agent for dotnet/aspnetcore for #68881 · auto · 27.1 AIC · ⌖ 10.4 AIC · ⊞ 27.5K · ◷

[damyanpetev]

For BL0015 (and others actually) not offering automatic code fix suggestions in Razor is expected: see dotnet/razor#11400 (comment) and dotnet/razor#6641
Note: That's in Razor only, not per project file, you can write C# classes server/client projects with interop logic (partial/razor.cs) and those will offer code fixes just fine :)

As for BL0016 if the only tested option is InvokeAsync (i.e. invoke with return value), that falls under the cases the fixer explicitly skips to avoid code fixed producing potentially invalid (along with lambda and return statements).

In the same app if the call was not an assignment or with InvokeVoidAsync the fix is offered just fine as well: