codex-team/editor.js · error · Error

Incorrect data passed to the render() method

Error message

Incorrect data passed to the render() method

What it means

BlocksAPI.render(data) requires a full saved document object with a `blocks` array; it validates that neither `data` nor `data.blocks` is undefined and throws otherwise. It exists to catch malformed saved data before the renderer runs.

Source

Thrown at src/components/modules/api/blocks.ts:206

    this.Editor.Toolbar.close();
  }

  /**
   * Clear Editor's area
   */
  public async clear(): Promise<void> {
    await this.Editor.BlockManager.clear(true);
    this.Editor.InlineToolbar.close();
  }

  /**
   * Fills Editor with Blocks data
   *
   * @param {OutputData} data — Saved Editor data
   */
  public async render(data: OutputData): Promise<void> {
    if (data === undefined || data.blocks === undefined) {
      throw new Error('Incorrect data passed to the render() method');
    }

    /**
     * Semantic meaning of the "render" method: "Display the new document over the existing one that stays unchanged"
     * So we need to disable modifications observer temporarily
     */
    this.Editor.ModificationsObserver.disable();

    await this.Editor.BlockManager.clear();
    await this.Editor.Renderer.render(data.blocks);

    this.Editor.ModificationsObserver.enable();
  }

  /**
   * Render passed HTML string
   *
   * @param {string} data - HTML string to render

View on GitHub (pinned to 5f45dabbe5)

Solutions

1. Verify the payload shape before calling render (data && Array.isArray(data.blocks))
2. Fix the producer: ensure save()/backend actually stores {blocks: [...]}
3. Default to empty document: render({ blocks: [] }) when data is missing

Example fix

// before
editor.blocks.render(JSON.parse(localStorage.getItem('draft')));
// after
const raw = localStorage.getItem('draft');
const data = raw ? JSON.parse(raw) : null;
editor.blocks.render(data && Array.isArray(data.blocks) ? data : { blocks: [] });

const isRenderable = (d: unknown): d is OutputData => !!d && Array.isArray((d as OutputData).blocks); if (!isRenderable(data)) data = { blocks: [] }; await editor.blocks.render(data);

const isOutputData = (d: unknown): d is OutputData => typeof d === 'object' && d !== null && Array.isArray((d as OutputData).blocks);

try { await editor.blocks.render(data); } catch (e) { if (e instanceof Error && e.message.includes('render() method')) { await editor.blocks.render({ blocks: [] }); return; } throw e; }

When it happens

Trigger: Calling `editor.blocks.render(undefined)`, `editor.blocks.render({})`, or passing a JSON-parsed payload whose blocks field is missing (e.g. wrong storage key or hand-mangled save file).

Common situations: Loading from localStorage where the saved item is absent or corrupt; backend returns `{time: ...}` without blocks; passing `editor.save()` output that was truncated or re-wrapped.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• «holderId» and «holder» param can't assign at the same time.
• Tool «${toolName}» must be a constructor function or an obje
• Unable to move Block down since it is already the last
• Unable to move Block up since it is already the first
• Block with id "${id}" not found

AI-assisted analysis of codex-team/editor.js@5f45dabbe5 (2026-08-27). Data as JSON: /api/errors/d176af9df4880a55. Report an issue: GitHub.