WRNexusJS/packages/email-renderer/test/email.test.ts

import { describe, expect, test } from "bun:test";
import { parse, type DefaultTreeAdapterMap } from "parse5";
import {
  emailCoreBlocks,
  renderEmail,
  validateAmpEmail,
  validateMjml,
  importMjml,
  type EmailRenderBundle,
} from "../src/index.ts";
import type { BlockDocument } from "@wrnexus/blocks";

const document: BlockDocument = {
  schemaVersion: 1,
  kind: "email",
  meta: { subject: "Welcome", preheader: "Preview", lang: "en" },
  theme: { tokens: {} },
  root: {
    id: "root",
    type: "layout.email-document",
    version: 1,
    props: { width: "600", background: "#f3f4f6" },
    styles: {},
    slots: {
      content: [
        {
          id: "section",
          type: "layout.section",
          version: 1,
          props: { background: "#ffffff", padding: "24px" },
          styles: {},
          slots: {
            content: [
              {
                id: "heading",
                type: "content.heading",
                version: 1,
                props: { text: "Hello <world>", level: "1" },
                styles: {},
                slots: {},
              },
              {
                id: "button",
                type: "content.button",
                version: 1,
                props: { label: "Open", href: "https://example.com/" },
                styles: {},
                slots: {},
              },
            ],
          },
        },
      ],
    },
  },
};

describe("email renderer", () => {
  test("browser HTML parsing preserves every block inside its section", async () => {
    const rendered = await renderEmail(document);
    expect(rendered.ok).toBe(true);
    if (!rendered.ok) return;
    const tree = parse(rendered.value.parts.html.content);
    const ancestry = new Map<string, string[]>();
    const walk = (node: DefaultTreeAdapterMap["node"], parents: string[]) => {
      const id = "attrs" in node ? node.attrs.find(attr => attr.name === "data-block-id")?.value : undefined;
      if (id) ancestry.set(id, parents);
      if ("childNodes" in node) for (const child of node.childNodes) walk(child, id ? [...parents, id] : parents);
    };
    walk(tree, []);
    expect(ancestry.get("heading")).toEqual(["root", "section"]);
    expect(ancestry.get("button")).toEqual(["root", "section"]);
  });
  test("renders deterministic HTML, text, AMP, and MJML", async () => {
    const first = await renderEmail(document, { amp: true, mjml: true });
    const second = await renderEmail(document, { amp: true, mjml: true });
    expect(first).toEqual(second);
    expect(first.ok).toBe(true);
    if (!first.ok) return;
    const value: EmailRenderBundle = first.value;
    expect(value.parts.html.content).toContain("Hello &lt;world&gt;");
    expect(value.parts.html.content).toContain("color:#111827");
    expect(value.parts.text.content).toContain("Hello <world>");
    expect(value.parts.amp?.validation.valid).toBe(true);
    expect(value.exports?.mjml).toContain("<mjml>");
  });

  test("validates AMP output", async () => {
    expect((await validateAmpEmail("<html></html>")).valid).toBe(false);
  });

  test("keeps rendered block rows inside valid column tables", async () => {
    const columnDocument = structuredClone(document);
    const content = columnDocument.root.slots.content[0]!.slots.content;
    columnDocument.root.slots.content[0]!.slots.content = [
      {
        id: "columns",
        type: "layout.columns",
        version: 1,
        props: {},
        styles: {},
        slots: {
          columns: [
            {
              id: "column",
              type: "layout.column",
              version: 1,
              props: { width: "100%" },
              styles: {},
              slots: { content },
            },
          ],
        },
      },
    ];
    const rendered = await renderEmail(columnDocument, { amp: true });
    expect(rendered.ok).toBe(true);
    if (!rendered.ok) return;
    expect(rendered.value.parts.html.content).toContain(
      'data-block-id="column" class="wrn-column" width="100%" valign="top"><table role="presentation"',
    );
    expect(rendered.value.parts.html.content).toContain(
      '<table role="presentation" width="100%" cellpadding="0" cellspacing="0" border="0"><tr><td data-block-id="heading"',
    );
  });

  test("compiles only allowlisted semantic styles", async () => {
    const styled = structuredClone(document);
    styled.root.slots.content[0]!.slots.content[0]!.styles = {
      color: { base: "#123456" },
      textAlign: { base: "center" },
      padding: { base: "12px 8px" },
      backgroundColor: { base: "red;position:fixed" },
    };
    const rendered = await renderEmail(styled);
    expect(rendered.ok).toBe(true);
    if (!rendered.ok) return;
    expect(rendered.value.parts.html.content).toContain(
      "color:#123456;padding:12px 8px;text-align:center",
    );
    expect(rendered.value.parts.html.content).not.toContain("position:fixed");
  });

  test("resolves allowlisted personalization values and fallbacks", async () => {
    const personalized = structuredClone(document);
    personalized.root.slots.content[0]!.slots.content[0]!.props.text =
      "Hello {{recipientName|friend}}";
    const rendered = await renderEmail(personalized, { variables: { recipientName: "Ada" } });
    expect(rendered.ok && rendered.value.parts.html.content).toContain("Hello Ada");
    const fallback = await renderEmail(personalized);
    expect(fallback.ok && fallback.value.parts.text.content).toContain("Hello friend");
    const strict = await renderEmail(personalized, { requireVariables: true });
    expect(strict.ok).toBe(true);
    personalized.root.slots.content[0]!.slots.content[0]!.props.text = "Hello {{recipientName}}";
    expect((await renderEmail(personalized, { requireVariables: true })).ok).toBe(false);
  });

  test("rejects unsafe MJML and imports supported content", () => {
    expect(
      importMjml("<mjml><mj-body><mj-raw>x</mj-raw></mj-body></mjml>", {
        id: () => crypto.randomUUID(),
        subject: "x",
      }).ok,
    ).toBe(false);
    let n = 0;
    const imported = importMjml(
      "<mjml><mj-body><mj-section><mj-column><mj-text>Hello</mj-text></mj-column></mj-section></mj-body></mjml>",
      { id: () => `n${++n}`, subject: "Imported" },
    );
    expect(imported.ok).toBe(true);
  });

  test("strict MJML validation catches invalid nesting", async () => {
    expect(
      (await validateMjml("<mjml><mj-body><mj-text>x</mj-text></mj-body></mjml>")).length,
    ).toBeGreaterThan(0);
  });

  test("ships the complete marketing block pack", () => {
    expect(emailCoreBlocks.map((block) => block.manifest.type)).toEqual(
      expect.arrayContaining([
        "content.video",
        "content.social",
        "content.countdown",
        "content.survey",
        "content.feed-item",
        "commerce.product",
      ]),
    );
    for (const block of emailCoreBlocks) {
      expect(block.textRenderer).toBeFunction();
      expect(block.renderers?.emailHtml).toBeFunction();
      expect(block.renderers?.ampEmail).toBeFunction();
      expect(block.renderers?.mjml).toBeFunction();
    }
  });
});