Suggestion node prop injection must target elements for inline voids

Problem

We moved date-node off direct suggestion helpers and into suggestion-driven node prop injection so the node could stay suggestion-agnostic. The first pass worked in focused tests but broke prerendering because the injection hook also ran for non-element nodes.

Symptoms

• pnpm turbo build --filter=./apps/www failed while prerendering /cn
• The crash stack pointed at the new suggestion transformProps path and an undefined element.children
• Inline date suggestion tests still passed, which made the failure easy to miss until full app build

What Didn't Work

• Adding a targetPlugins: [KEYS.date] guard alone. inject.nodeProps still visits text nodes, and targetPlugins only filters when an element type exists.
• Using a typed no-op transformProps without an explicit element guard. Runtime prerender still reached the helper with element === undefined.

Solution

Constrain the suggestion injection to elements and keep the date component generic:

inject: {
  isElement: true,
  nodeProps: {
    nodeKey: '',
    styleKey: 'cssText',
    transformProps: ({ editor, element, props }) => {
      if (!element) return props;

      const suggestionApi = editor.getApi(BaseSuggestionPlugin).suggestion;
      const suggestionData = suggestionApi.suggestionData(element);

      if (!suggestionData) return props;

      return {
        ...props,
        'data-inline-suggestion': suggestionData.type,
      };
    },
    transformStyle: () => ({}) as CSSStyleDeclaration,
  },
  targetPlugins: [KEYS.date],
},

Then let date-node expose only a stable slot plus ancestor-aware variants:

<span
  className={cn(
    'w-fit cursor-pointer rounded-sm bg-muted px-1 text-muted-foreground',
    'in-data-[inline-suggestion=insert]:bg-emerald-100! in-data-[inline-suggestion=insert]:text-emerald-700!',
    'in-data-[inline-suggestion=remove]:bg-red-100! in-data-[inline-suggestion=remove]:text-red-700!'
  )}
  data-slot="date-trigger"
  draggable
>

Why This Works

inject.nodeProps is broader than an element-only render hook. It participates in the generic render prop pipeline, so text nodes can still arrive unless the plugin opts into isElement: true. Once the injected state is guaranteed to live on element roots, the inline void component can stay decoupled and style itself through stable slots plus ancestor data attributes.

Prevention

• When adding inject.nodeProps behavior that calls element helpers, set isElement: true unless the transform is intentionally text-safe.
• If targetPlugins is meant to protect element-only logic, still add an explicit element null guard in transformProps.
• Keep one targeted test for the component contract and one plugin-level test for the injected data attribute, then run a real app build to catch prerender-only failures.

Related Issues

• 2026-04-08-suggestion-delete-backward-must-mark-inline-voids.md