Markdown Table Snapshot

The toMatchMarkdownTableSnapshotFile matcher creates a readable Markdown table representation from HTML <table> elements or ARIA grid elements. This format is ideal for snapshot testing of tabular data in a human-readable format.

Purpose

Markdown table snapshots provide:

• Human-readable output: Tables are rendered in Markdown format, making test snapshots easy to review
• Table-specific testing: Focus on tabular data structure and content without the noise of full element snapshots
• Sort indicator support: Optionally display sorting state for sortable column headers

Usage

import { defineElementSnapshotMatchers } from "@cronn/element-snapshot";

const expect = defineElementSnapshotMatchers();

test("matches table snapshot", async ({ page }) => {
  await expect(page.getByRole("table")).toMatchMarkdownTableSnapshotFile();
});

Options

The markdownTableSnapshot function accepts an optional second parameter with the following options:

Option	Type	Default	Description
showSortIndicator	boolean	false	Display sort indicators next to sorted column headers

Sort Indicators

When showSortIndicator is enabled, column headers with aria-sort attributes will display:

• ⯅ for ascending sort
• ⯆ for descending sort
• ◆ for other sort types

Examples

HTML Table with Row Headers

test("employee table", async ({ page }) => {
  await page.setContent(`
    <table>
      <thead>
        <tr>
          <th scope="col">Employee</th>
          <th scope="col">Department</th>
          <th scope="col">Salary</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <th scope="row">Alice Johnson</th>
          <td>Engineering</td>
          <td>$95,000</td>
        </tr>
        <tr>
          <th scope="row">Bob Smith</th>
          <td>Marketing</td>
          <td>$75,000</td>
        </tr>
      </tbody>
    </table>
  `);

  await expect(page.getByRole("table")).toMatchMarkdownTableSnapshotFile();
});

Output:

| Employee      | Department  | Salary  |
| ------------- | ----------- | ------- |
| Alice Johnson | Engineering | $95,000 |
| Bob Smith     | Marketing   | $75,000 |

ARIA Grid

test("product grid", async ({ page }) => {
  await page.setContent(`
    <div role="grid">
      <div role="row">
        <div role="columnheader">Product</div>
        <div role="columnheader">Price</div>
        <div role="columnheader">Stock</div>
      </div>
      <div role="row">
        <div role="gridcell">Laptop</div>
        <div role="gridcell">$999</div>
        <div role="gridcell">15</div>
      </div>
      <div role="row">
        <div role="gridcell">Mouse</div>
        <div role="gridcell">$25</div>
        <div role="gridcell">150</div>
      </div>
    </div>
  `);

  await expect(page.getByRole("grid")).toMatchMarkdownTableSnapshotFile();
});

Output:

| Product | Price | Stock |
| ------- | ----- | ----- |
| Laptop  | $999  | 15    |
| Mouse   | $25   | 150   |

Sorted Column Headers

test("sorted table", async ({ page }) => {
  await page.setContent(`
    <table>
      <thead>
        <tr>
          <th scope="col" aria-sort="descending">Name</th>
          <th scope="col">Score</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td>Alice</td>
          <td>95</td>
        </tr>
        <tr>
          <td>Bob</td>
          <td>88</td>
        </tr>
      </tbody>
    </table>
  `);

  await expect(page.getByRole("table")).toMatchMarkdownTableSnapshotFile();
});

Output:

| Name ⯆ | Score |
| ------ | ----- |
| Alice  | 95    |
| Bob    | 88    |

Snapshot Function

The markdownTableSnapshot function provides more flexibility than the toMatchMarkdownTableSnapshotFile matcher, because it returns the snapshot result as a Markdown string instead of directly writing it to a file. This makes it suitable for composing custom assertions:

import { markdownTableSnapshot } from "@cronn/element-snapshot";

test("processes markdown table snapshot result", async ({ page }) => {
  await page.setContent(`
    <table>
      <thead>
        <tr>
          <th scope="col">Name</th>
          <th scope="col">Score</th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <td>Alice</td>
          <td>95</td>
        </tr>
      </tbody>
    </table>
  `);

  const markdownTable = await markdownTableSnapshot(page.getByRole("table"));
  expect(markdownTable).toContain("Alice");
});

Supported Elements

The markdownTableSnapshot function works with:

• HTML <table> elements
• ARIA grid elements (with role="grid")
• Any element with role="table"

It requires:

• At least one row with role="row"
• A header row containing columnheader elements
• Body rows containing cell, gridcell, or rowheader elements