3.2 KiB
class: SnapshotAssertions
- since: v1.20
- langs: js
Playwright provides methods for comparing page and element screenshots with expected values stored in files.
expect(screenshot).toMatchSnapshot('landing-page.png');
method: SnapshotAssertions.toMatchSnapshot#1
- since: v1.22
:::caution
To compare screenshots, use [method: PageAssertions.toHaveScreenshot#1] instead.
:::
Ensures that passed value, either a [string] or a [Buffer], matches the expected snapshot stored in the test snapshots directory.
Usage
// Basic usage.
expect(await page.screenshot()).toMatchSnapshot('landing-page.png');
// Pass options to customize the snapshot comparison and have a generated name.
expect(await page.screenshot()).toMatchSnapshot('landing-page.png', {
maxDiffPixels: 27, // allow no more than 27 different pixels.
});
// Configure image matching threshold.
expect(await page.screenshot()).toMatchSnapshot('landing-page.png', { threshold: 0.3 });
// Bring some structure to your snapshot files by passing file path segments.
expect(await page.screenshot()).toMatchSnapshot(['landing', 'step2.png']);
expect(await page.screenshot()).toMatchSnapshot(['landing', 'step3.png']);
Learn more about visual comparisons.
Note that matching snapshots only work with Playwright test runner.
param: SnapshotAssertions.toMatchSnapshot#1.name
- since: v1.22
name<[string]|[Array]<[string]>>
Snapshot name.
option: SnapshotAssertions.toMatchSnapshot#1.maxDiffPixels = %%-assertions-max-diff-pixels-%%
- since: v1.22
option: SnapshotAssertions.toMatchSnapshot#1.maxDiffPixelRatio = %%-assertions-max-diff-pixel-ratio-%%
- since: v1.22
option: SnapshotAssertions.toMatchSnapshot#1.threshold = %%-assertions-threshold-%%
- since: v1.22
method: SnapshotAssertions.toMatchSnapshot#2
- since: v1.22
:::caution
To compare screenshots, use [method: PageAssertions.toHaveScreenshot#2] instead.
:::
Ensures that passed value, either a [string] or a [Buffer], matches the expected snapshot stored in the test snapshots directory.
Usage
// Basic usage and the file name is derived from the test name.
expect(await page.screenshot()).toMatchSnapshot();
// Pass options to customize the snapshot comparison and have a generated name.
expect(await page.screenshot()).toMatchSnapshot({
maxDiffPixels: 27, // allow no more than 27 different pixels.
});
// Configure image matching threshold and snapshot name.
expect(await page.screenshot()).toMatchSnapshot({
name: 'landing-page.png',
threshold: 0.3,
});
Learn more about visual comparisons.
Note that matching snapshots only work with Playwright test runner.
option: SnapshotAssertions.toMatchSnapshot#2.maxDiffPixels = %%-assertions-max-diff-pixels-%%
- since: v1.22
option: SnapshotAssertions.toMatchSnapshot#2.maxDiffPixelRatio = %%-assertions-max-diff-pixel-ratio-%%
- since: v1.22
option: SnapshotAssertions.toMatchSnapshot#2.name
- since: v1.22
name<[string]|[Array]<[string]>>
Snapshot name. If not passed, the test name and ordinals are used when called multiple times.
option: SnapshotAssertions.toMatchSnapshot#2.threshold = %%-assertions-threshold-%%
- since: v1.22