feat: Add Page.expect_screenshot/2#56
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Beautiful. Some tiny suggestions and one question.
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When writing browser tests, we sometimes need to assert visual changes in elements — layout shifts, style regressions, rendering differences. `@playwright/test` ships `toHaveScreenshot` for exactly this, but it's not accessible from Elixir. This PR introduces `assert_screenshot/3`, a helper built on the same underlying Playwright `expectScreenshot` protocol command that powers `toHaveScreenshot`. On the first run, it captures a screenshot and saves it as the baseline. On subsequent runs, it compares the live page against that baseline server-side, passing silently on match, failing with a diff image on mismatch. Note: depends on ftes/playwright_ex#56. The `mix.exs` points at that branch and will need updating once it merges. --------- Co-authored-by: Fredrik Teschke <f@ftes.de>
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@playwright/testshipstoHaveScreenshotfor visual regression testing, but the underlyingexpectScreenshotprotocol command was not exposed in this library. This PR addsPage.expect_screenshot/2, including alocatoropt to scope the screenshot to a specific element, to support building atoHaveScreenshot-equivalent helper in Elixir.