feat: release "comparator" option from experiment (#20720)

The option defines a comparator to be used to compare images.
Possible values are `"pixelmatch"` and `"ssim-cie94"`.

Note: This reverts commit 8167f8bf54.

docs/src/api/class-locatorassertions.md

@@ -1362,6 +1362,9 @@ Snapshot name.
 ### option: LocatorAssertions.toHaveScreenshot#1.scale = %%-screenshot-option-scale-default-css-%%
 * since: v1.23
 
+### option: LocatorAssertions.toHaveScreenshot#1.comparator = %%-assertions-comparator-%%
+* since: v1.31
+
 ### option: LocatorAssertions.toHaveScreenshot#1.maxDiffPixels = %%-assertions-max-diff-pixels-%%
 * since: v1.23
 
@@ -1405,6 +1408,9 @@ Note that screenshot assertions only work with Playwright test runner.
 ### option: LocatorAssertions.toHaveScreenshot#2.scale = %%-screenshot-option-scale-default-css-%%
 * since: v1.23
 
+### option: LocatorAssertions.toHaveScreenshot#2.comparator = %%-assertions-comparator-%%
+* since: v1.31
+
 ### option: LocatorAssertions.toHaveScreenshot#2.maxDiffPixels = %%-assertions-max-diff-pixels-%%
 * since: v1.23
 

docs/src/api/class-pageassertions.md

@@ -170,6 +170,9 @@ Snapshot name.
 ### option: PageAssertions.toHaveScreenshot#1.scale = %%-screenshot-option-scale-default-css-%%
 * since: v1.23
 
+### option: PageAssertions.toHaveScreenshot#1.comparator = %%-assertions-comparator-%%
+* since: v1.29
+
 ### option: PageAssertions.toHaveScreenshot#1.maxDiffPixels = %%-assertions-max-diff-pixels-%%
 * since: v1.23
 
@@ -218,6 +221,9 @@ Note that screenshot assertions only work with Playwright test runner.
 ### option: PageAssertions.toHaveScreenshot#2.scale = %%-screenshot-option-scale-default-css-%%
 * since: v1.23
 
+### option: PageAssertions.toHaveScreenshot#2.comparator = %%-assertions-comparator-%%
+* since: v1.29
+
 ### option: PageAssertions.toHaveScreenshot#2.maxDiffPixels = %%-assertions-max-diff-pixels-%%
 * since: v1.23
 

docs/src/api/class-snapshotassertions.md

@@ -43,6 +43,9 @@ Note that matching snapshots only work with Playwright test runner.
 
 Snapshot name.
 
+### option: SnapshotAssertions.toMatchSnapshot#1.comparator = %%-assertions-comparator-%%
+* since: v1.29
+
 ### option: SnapshotAssertions.toMatchSnapshot#1.maxDiffPixels = %%-assertions-max-diff-pixels-%%
 * since: v1.22
 
@@ -79,6 +82,9 @@ Learn more about [visual comparisons](../test-snapshots.md).
 
 Note that matching snapshots only work with Playwright test runner.
 
+### option: SnapshotAssertions.toMatchSnapshot#2.comparator = %%-assertions-comparator-%%
+* since: v1.29
+
 ### option: SnapshotAssertions.toMatchSnapshot#2.maxDiffPixels = %%-assertions-max-diff-pixels-%%
 * since: v1.22
 

docs/src/api/params.md

@@ -812,6 +812,12 @@ Time to retry the assertion for.
 
 An acceptable amount of pixels that could be different. Default is configurable with `TestConfig.expect`. Unset by default.
 
+## assertions-comparator
+* langs: js
+- `comparator` <[string]> Either `"pixelmatch"` or `"ssim-cie94"`.
+
+A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+
 ## assertions-max-diff-pixel-ratio
 * langs: js
 - `maxDiffPixelRatio` <[float]>
@@ -824,7 +830,7 @@ An acceptable ratio of pixels that are different to the total amount of pixels,
 
 An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ)
 between the same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-`TestConfig.expect`. Defaults to `0.2`.
+`TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
 
 ## shared-context-params-list-v1.8
 - %%-context-option-acceptdownloads-%%

docs/src/test-api/class-testconfig.md

@@ -37,14 +37,16 @@ export default defineConfig({
 - type: ?<[Object]>
   - `timeout` ?<[int]> Default timeout for async expect matchers in milliseconds, defaults to 5000ms.
   - `toHaveScreenshot` ?<[Object]> Configuration for the [`method: PageAssertions.toHaveScreenshot#1`] method.
-    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+    - `comparator` ?<[string]> a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used by `pixelmatch` image comparator.
     - `maxDiffPixels` ?<[int]> an acceptable amount of pixels that could be different, unset by default.
     - `maxDiffPixelRatio` ?<[float]> an acceptable ratio of pixels that are different to the total amount of pixels, between `0` and `1` , unset by default.
     - `animations` ?<[ScreenshotAnimations]<"allow"|"disabled">> See [`option: animations`] in [`method: Page.screenshot`]. Defaults to `"disabled"`.
     - `caret` ?<[ScreenshotCaret]<"hide"|"initial">> See [`option: caret`] in [`method: Page.screenshot`]. Defaults to `"hide"`.
     - `scale` ?<[ScreenshotScale]<"css"|"device">> See [`option: scale`] in [`method: Page.screenshot`]. Defaults to `"css"`.
   - `toMatchSnapshot` ?<[Object]> Configuration for the [`method: SnapshotAssertions.toMatchSnapshot#1`] method.
-    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+    - `comparator` ?<[string]> a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used by `pixelmatch` image comparator.
     - `maxDiffPixels` ?<[int]> an acceptable amount of pixels that could be different, unset by default.
     - `maxDiffPixelRatio` ?<[float]> an acceptable ratio of pixels that are different to the total amount of pixels, between `0` and `1` , unset by default.
 

docs/src/test-api/class-testproject.md

@@ -133,14 +133,16 @@ export default defineConfig({
 - type: ?<[Object]>
   - `timeout` ?<[int]> Default timeout for async expect matchers in milliseconds, defaults to 5000ms.
   - `toHaveScreenshot` ?<[Object]> Configuration for the [`method: PageAssertions.toHaveScreenshot#1`] method.
-    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+    - `comparator` ?<[string]> a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used by `pixelmatch` image comparator.
     - `maxDiffPixels` ?<[int]> an acceptable amount of pixels that could be different, unset by default.
     - `maxDiffPixelRatio` ?<[float]> an acceptable ratio of pixels that are different to the total amount of pixels, between `0` and `1` , unset by default.
     - `animations` ?<[ScreenshotAnimations]<"allow"|"disabled">> See [`option: animations`] in [`method: Page.screenshot`]. Defaults to `"disabled"`.
     - `caret` ?<[ScreenshotCaret]<"hide"|"initial">> See [`option: caret`] in [`method: Page.screenshot`]. Defaults to `"hide"`.
     - `scale` ?<[ScreenshotScale]<"css"|"device">> See [`option: scale`] in [`method: Page.screenshot`]. Defaults to `"css"`.
   - `toMatchSnapshot` ?<[Object]> Configuration for the [`method: SnapshotAssertions.toMatchSnapshot#1`] method.
-    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+    - `comparator` ?<[string]> a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+    - `threshold` ?<[float]> an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and `1` (lax). `"pixelmatch"` comparator computes color difference in [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used by `pixelmatch` image comparator.
     - `maxDiffPixels` ?<[int]> an acceptable amount of pixels that could be different, unset by default.
     - `maxDiffPixelRatio` ?<[float]> an acceptable ratio of pixels that are different to the total amount of pixels, between `0` and `1` , unset by default.
 

packages/playwright-core/src/server/dispatchers/pageDispatcher.ts

@@ -181,10 +181,6 @@ export class PageDispatcher extends Dispatcher<Page, channels.PageChannel, Brows
     return await this._page.expectScreenshot(metadata, {
       ...params,
       locator,
-      comparatorOptions: {
-        ...params.comparatorOptions,
-        _comparator: params.comparatorOptions?.comparator,
-      },
       screenshotOptions: {
         ...params.screenshotOptions,
         mask,

packages/playwright-core/src/utils/comparators.ts

@@ -21,7 +21,7 @@ import { compare } from '../image_tools/compare';
 const { diff_match_patch, DIFF_INSERT, DIFF_DELETE, DIFF_EQUAL } = require('../third_party/diff_match_patch');
 import { PNG } from '../utilsBundle';
 
-export type ImageComparatorOptions = { threshold?: number, maxDiffPixels?: number, maxDiffPixelRatio?: number, _comparator?: string };
+export type ImageComparatorOptions = { threshold?: number, maxDiffPixels?: number, maxDiffPixelRatio?: number, comparator?: string };
 export type ComparatorResult = { diff?: Buffer; errorMessage: string; } | null;
 export type Comparator = (actualBuffer: Buffer | string, expectedBuffer: Buffer, options?: any) => ComparatorResult;
 
@@ -64,18 +64,18 @@ function compareImages(mimeType: string, actualBuffer: Buffer | string, expected
   }
   const diff = new PNG({ width: size.width, height: size.height });
   let count;
-  if (options._comparator === 'ssim-cie94') {
+  if (options.comparator === 'ssim-cie94') {
     count = compare(expected.data, actual.data, diff.data, size.width, size.height, {
       // All ΔE* formulae are originally designed to have the difference of 1.0 stand for a "just noticeable difference" (JND).
       // See https://en.wikipedia.org/wiki/Color_difference#CIELAB_%CE%94E*
       maxColorDeltaE94: 1.0,
     });
-  } else if ((options._comparator ?? 'pixelmatch') === 'pixelmatch') {
+  } else if ((options.comparator ?? 'pixelmatch') === 'pixelmatch') {
     count = pixelmatch(expected.data, actual.data, diff.data, size.width, size.height, {
       threshold: options.threshold ?? 0.2,
     });
   } else {
-    throw new Error(`Configuration specifies unknown comparator "${options._comparator}"`);
+    throw new Error(`Configuration specifies unknown comparator "${options.comparator}"`);
   }
 
   const maxDiffPixels1 = options.maxDiffPixels;

packages/playwright-test/src/matchers/toMatchSnapshot.ts

@@ -145,7 +145,7 @@ class SnapshotHelper<T extends ImageComparatorOptions> {
       maxDiffPixels: options.maxDiffPixels,
       maxDiffPixelRatio: options.maxDiffPixelRatio,
       threshold: options.threshold,
-      _comparator: options._comparator,
+      comparator: options.comparator,
     };
     this.kind = this.mimeType.startsWith('image/') ? 'Screenshot' : 'Snapshot';
   }
@@ -306,7 +306,7 @@ export async function toHaveScreenshot(
   const helper = new SnapshotHelper(
       testInfo, snapshotPathResolver, 'png',
       {
-        _comparator: config?._comparator,
+        comparator: config?.comparator,
         maxDiffPixels: config?.maxDiffPixels,
         maxDiffPixelRatio: config?.maxDiffPixelRatio,
         threshold: config?.threshold,
@@ -342,10 +342,7 @@ export async function toHaveScreenshot(
       expected: await fs.promises.readFile(helper.snapshotPath),
       isNot: true,
       locator,
-      comparatorOptions: {
-        ...helper.comparatorOptions,
-        comparator: helper.comparatorOptions._comparator,
-      },
+      comparatorOptions: helper.comparatorOptions,
       screenshotOptions,
       timeout: currentExpectTimeout(helper.allOptions),
     })).errorMessage;
@@ -363,7 +360,7 @@ export async function toHaveScreenshot(
       expected: undefined,
       isNot: false,
       locator,
-      comparatorOptions: { ...helper.comparatorOptions, comparator: helper.comparatorOptions._comparator },
+      comparatorOptions: helper.comparatorOptions,
       screenshotOptions,
       timeout,
     });
@@ -385,7 +382,7 @@ export async function toHaveScreenshot(
     expected,
     isNot: false,
     locator,
-    comparatorOptions: { ...helper.comparatorOptions, comparator: helper.comparatorOptions._comparator },
+    comparatorOptions: helper.comparatorOptions,
     screenshotOptions,
     timeout: currentExpectTimeout(helper.allOptions),
   });

packages/playwright-test/types/test.d.ts

@@ -551,10 +551,16 @@ interface TestConfig {
      * method.
      */
     toHaveScreenshot?: {
+      /**
+       * a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+       */
+      comparator?: string;
+
       /**
        * an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and
        * `1` (lax). `"pixelmatch"` comparator computes color difference in
-       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used
+       * by `pixelmatch` image comparator.
        */
       threshold?: number;
 
@@ -594,10 +600,16 @@ interface TestConfig {
      * method.
      */
     toMatchSnapshot?: {
+      /**
+       * a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+       */
+      comparator?: string;
+
       /**
        * an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and
        * `1` (lax). `"pixelmatch"` comparator computes color difference in
-       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used
+       * by `pixelmatch` image comparator.
        */
       threshold?: number;
 
@@ -4731,6 +4743,11 @@ interface LocatorAssertions {
      */
     caret?: "hide"|"initial";
 
+    /**
+     * A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+     */
+    comparator?: string;
+
     /**
      * Specify locators that should be masked when the screenshot is taken. Masked elements will be overlaid with a pink
      * box `#FF00FF` that completely covers its bounding box.
@@ -4767,7 +4784,7 @@ interface LocatorAssertions {
     /**
      * An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) between the
      * same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-     * `TestConfig.expect`. Defaults to `0.2`.
+     * `TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
      */
     threshold?: number;
 
@@ -4808,6 +4825,11 @@ interface LocatorAssertions {
      */
     caret?: "hide"|"initial";
 
+    /**
+     * A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+     */
+    comparator?: string;
+
     /**
      * Specify locators that should be masked when the screenshot is taken. Masked elements will be overlaid with a pink
      * box `#FF00FF` that completely covers its bounding box.
@@ -4844,7 +4866,7 @@ interface LocatorAssertions {
     /**
      * An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) between the
      * same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-     * `TestConfig.expect`. Defaults to `0.2`.
+     * `TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
      */
     threshold?: number;
 
@@ -5056,6 +5078,11 @@ interface PageAssertions {
       height: number;
     };
 
+    /**
+     * A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+     */
+    comparator?: string;
+
     /**
      * When true, takes a screenshot of the full scrollable page, instead of the currently visible viewport. Defaults to
      * `false`.
@@ -5098,7 +5125,7 @@ interface PageAssertions {
     /**
      * An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) between the
      * same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-     * `TestConfig.expect`. Defaults to `0.2`.
+     * `TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
      */
     threshold?: number;
 
@@ -5163,6 +5190,11 @@ interface PageAssertions {
       height: number;
     };
 
+    /**
+     * A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+     */
+    comparator?: string;
+
     /**
      * When true, takes a screenshot of the full scrollable page, instead of the currently visible viewport. Defaults to
      * `false`.
@@ -5205,7 +5237,7 @@ interface PageAssertions {
     /**
      * An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) between the
      * same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-     * `TestConfig.expect`. Defaults to `0.2`.
+     * `TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
      */
     threshold?: number;
 
@@ -5293,6 +5325,11 @@ interface SnapshotAssertions {
    * @param options
    */
   toMatchSnapshot(name: string|Array<string>, options?: {
+    /**
+     * A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+     */
+    comparator?: string;
+
     /**
      * An acceptable ratio of pixels that are different to the total amount of pixels, between `0` and `1`. Default is
      * configurable with `TestConfig.expect`. Unset by default.
@@ -5308,7 +5345,7 @@ interface SnapshotAssertions {
     /**
      * An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) between the
      * same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-     * `TestConfig.expect`. Defaults to `0.2`.
+     * `TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
      */
     threshold?: number;
   }): void;
@@ -5341,6 +5378,11 @@ interface SnapshotAssertions {
    * @param options
    */
   toMatchSnapshot(options?: {
+    /**
+     * A comparator function to use when comparing images. Defaults to `"pixelmatch"`.
+     */
+    comparator?: string;
+
     /**
      * An acceptable ratio of pixels that are different to the total amount of pixels, between `0` and `1`. Default is
      * configurable with `TestConfig.expect`. Unset by default.
@@ -5361,7 +5403,7 @@ interface SnapshotAssertions {
     /**
      * An acceptable perceived color difference in the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) between the
      * same pixel in compared images, between zero (strict) and one (lax), default is configurable with
-     * `TestConfig.expect`. Defaults to `0.2`.
+     * `TestConfig.expect`. Defaults to `0.2`. This option is used by "pixelmatch" image comparator.
      */
     threshold?: number;
   }): void;
@@ -5498,10 +5540,16 @@ interface TestProject {
      * method.
      */
     toHaveScreenshot?: {
+      /**
+       * a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+       */
+      comparator?: string;
+
       /**
        * an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and
        * `1` (lax). `"pixelmatch"` comparator computes color difference in
-       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used
+       * by `pixelmatch` image comparator.
        */
       threshold?: number;
 
@@ -5541,10 +5589,16 @@ interface TestProject {
      * method.
      */
     toMatchSnapshot?: {
+      /**
+       * a comparator function to use, either `"pixelmatch"` or `"ssim-cie94"`. Defaults to `"pixelmatch"`.
+       */
+      comparator?: string;
+
       /**
        * an acceptable perceived color difference between the same pixel in compared images, ranging from `0` (strict) and
        * `1` (lax). `"pixelmatch"` comparator computes color difference in
-       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`.
+       * [YIQ color space](https://en.wikipedia.org/wiki/YIQ) and defaults `threshold` value to `0.2`. This option is used
+       * by `pixelmatch` image comparator.
        */
       threshold?: number;
 

tests/config/comparator.ts

@@ -22,5 +22,5 @@ type ImageComparatorOptions = { threshold?: number, maxDiffPixels?: number, maxD
 
 export function comparePNGs(actual: Buffer, expected: Buffer, options: ImageComparatorOptions = {}): ComparatorResult {
   // Strict threshold by default in our tests.
-  return pngComparator(actual, expected, { _comparator: 'ssim-cie94', threshold: 0, ...options });
+  return pngComparator(actual, expected, { comparator: 'ssim-cie94', threshold: 0, ...options });
 }

tests/library/playwright.config.ts

@@ -47,8 +47,8 @@ const config: Config<CoverageWorkerOptions & PlaywrightWorkerOptions & Playwrigh
   outputDir,
   expect: {
     timeout: 10000,
-    toHaveScreenshot: { _comparator: 'ssim-cie94' } as any,
-    toMatchSnapshot: { _comparator: 'ssim-cie94' } as any,
+    toHaveScreenshot: { comparator: 'ssim-cie94' } as any,
+    toMatchSnapshot: { comparator: 'ssim-cie94' } as any,
   },
   maxFailures: 100,
   timeout: video ? 60000 : 30000,

tests/playwright-test/golden.spec.ts

@@ -631,13 +631,13 @@ test('should respect comparator name', async ({ runInlineTest }) => {
       test('should pass', ({}) => {
         expect(Buffer.from('${actual.toString('base64')}', 'base64')).toMatchSnapshot('snapshot.png', {
           threshold: 0,
-          _comparator: 'ssim-cie94',
+          comparator: 'ssim-cie94',
         });
       });
       test('should fail', ({}) => {
         expect(Buffer.from('${actual.toString('base64')}', 'base64')).toMatchSnapshot('snapshot.png', {
           threshold: 0,
-          _comparator: 'pixelmatch',
+          comparator: 'pixelmatch',
         });
       });
     `
@@ -662,7 +662,7 @@ test('should respect comparator in config', async ({ runInlineTest }) => {
             name: 'should-pass',
             expect: {
               toMatchSnapshot: {
-                _comparator: 'ssim-cie94',
+                comparator: 'ssim-cie94',
               }
             },
           },
@@ -670,7 +670,7 @@ test('should respect comparator in config', async ({ runInlineTest }) => {
             name: 'should-fail',
             expect: {
               toMatchSnapshot: {
-                _comparator: 'pixelmatch',
+                comparator: 'pixelmatch',
               }
             },
           },

tests/playwright-test/to-have-screenshot.spec.ts

@@ -1040,14 +1040,14 @@ test('should respect comparator name', async ({ runInlineTest }) => {
         await page.goto('${actualURL}');
         await expect(page.locator('img')).toHaveScreenshot('snapshot.png', {
           threshold: 0,
-          _comparator: 'ssim-cie94',
+          comparator: 'ssim-cie94',
         });
       });
       pwt.test('should fail', async ({ page }) => {
         await page.goto('${actualURL}');
         await expect(page.locator('img')).toHaveScreenshot('snapshot.png', {
           threshold: 0,
-          _comparator: 'pixelmatch',
+          comparator: 'pixelmatch',
         });
       });
     `
@@ -1070,7 +1070,7 @@ test('should respect comparator in config', async ({ runInlineTest }) => {
           name: 'should-pass',
           expect: {
             toHaveScreenshot: {
-              _comparator: 'ssim-cie94',
+              comparator: 'ssim-cie94',
             }
           },
         },
@@ -1078,7 +1078,7 @@ test('should respect comparator in config', async ({ runInlineTest }) => {
           name: 'should-fail',
           expect: {
             toHaveScreenshot: {
-              _comparator: 'pixelmatch',
+              comparator: 'pixelmatch',
             }
           },
         },