Bug fix for StencilJS compatibility

[kelseythejackson]

Fixes #1919

Custom-elements-jsx.d.ts generating "onundefined" event handlers

The Custom Elements Manifest analyzer was detecting events in two ways: from @event JSDoc tags (which include event names) and from analyzing dispatchEvent() calls in code (which only captured the type, not the name). This created duplicate event entries where some had only a type but no name, causing the JSX types generator to produce onundefined event handlers instead of proper names like "onwa-error".

Added a wa-filter-unnamed-events plugin that removes events without names before the JSX types are generated. This fixes 25 broken event entries across components, including wa-icon, wa-button, wa-input, wa-select, wa-dialog, wa-drawer, wa-dropdown, wa-tooltip, and others.

Also added a verification step to the build process that checks for unnamed events in the CEM and onundefined in the generated JSX types. The build will fail if these issues are detected, preventing regression.

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Project	Deployment	Actions	Updated (UTC)
webawesome	Ready	Preview	Feb 20, 2026 7:34pm

[claviska]

I'm not sure this is the right fix, but if @JohnHardy can verify if it actually works I'd be more apt to entertain it.

This also might be fixed by #1925. Unfortunately, we had to revert the original PR but putting this burden on a CEM plugin that generates the correct types would be much better than trying to patch it with a filter plugin.

Also, any CEM validation should be part of generateManifest(), not a separate build step.

[JohnHardy]

I'll test it as soon as I can, thank you for doing this! 🙏

[kelseythejackson]

Updated to remove the file and add validation to generateManifest(), if the aforementioned PR doesn't fix it, this is ready to go.

[claviska]

I'm fine with the update to custom-elements-manifest.js but I'm not sure we want to put verifications directly in build.js. If we're just filtering unnamed events, the plugin seems to handle that well enough to make the verification redundant.

I'd suggest reverting build.js and, if any of that code is actually executing, fix the plugin to ensure it works properly.

stale