toMatchTextFile

Asserts that a string value matches a text file snapshot. The string is trimmed and compared to a stored validation file. Supports retries when a callback function is provided as the actual value.

Usage

Static Snapshot

test("matches page title", async () => {
  await page.setContent("<title>Page Title</title>");

  await expect(page.title()).toMatchTextFile();
});

Output (matches_page_title.txt):

Page Title

Repeatable Snapshot

When passing a callback function as actual value, the snapshot will be retried until it matches the stored validation file:

test("matches page title eventually", async () => {
  await page.setContent("<title>Page Title</title>");

  await expect(() => page.title()).toMatchTextFile();
});

Custom File Extension

Use fileExtension to store snapshots with a different file extension:

test("matches HTML snapshot", async ({ page }) => {
  await page.setContent("<main>Hello World</main>");

  await expect(() => page.getByRole("main").innerHTML()).toMatchTextFile({
    fileExtension: "html",
  });
});

Output (matches_HTML_snapshot.html):

<main>Hello World</main>

Options

Option	Default Value	Description
fileExtension	txt	File extension used for storing the snapshot file.
name	undefined	Unique name of the file snapshot. Used to distinguish multiple file snapshots within the same test. See Named Snapshots.
normalizers	[]	Custom normalizers to apply before serialization. See Normalization of Snapshots.
timeout	expect timeout	Retries the snapshot until it passes or the timeout is reached. Only applies when a callback is passed. See Snapshot Retries.
updateDelay	250	Delay in ms before a repeatable snapshot is created in update mode. See Snapshot Retries.
resolveFilePath	resolveNameAsFile	Custom resolver for the file path used to store snapshots. See Named Snapshots.