[Feature] a toMatchScreenshot() for comparing two different screenshots

We currently have expect(screenshot).toMatchSnapshot(name[, options]) which is nice when comparing against at snapshot but it doesn’t work when comparing a screenshot against a reference website which is useful for doing visual regression to see what has changed. I propose that we add a toMatchScreenshot(screenshot[, options]) that could be used for something like this:

page.goto("production.example.com")
const ref = await page.screenshot({
  animations: "disabled",
  fullPage: true,
  scale: "css"
});

page.goto("localhost:8080")
const test = await page.screenshot({
  animations: "disabled",
  fullPage: true,
  scale: "css"
});

expect(test, "should  match reference").toMatchScreenshot(ref, {
  maxDiffPixelRatio: 0,
  maxDiffPixels: 0,
  threshold: 0
});

[aslushnikov]

@NikkTod no, it’s not coming to 1.29. Will be moved to 1.30 instead

[dgozman]

@ambiguous48 Yes, so far I think that toMatchImage() could support both buffers and file paths.