Instruction file imported from zNatix/pr-reviewer-agent (.github/instructions/playwright-anti-patterns.instructions.md). Copyright stays with the author.

Playwright for .NET — Anti-patterns

🚫 Anti-patterns to Flag Immediately

🔴 Critical — Block Merge

• new Playwright() or manual lifecycle management of IBrowser/IBrowserContext — use base classes
• .Result or .Wait() on async Playwright methods — always await
• Thread.Sleep() or Task.Delay() as synchronization mechanism — use assertions with auto-wait
• Hardcoded URLs in tests (use ContextOptions().BaseURL or configuration)
• Missing teardown for manually created resources (custom contexts, RouteAsync, external servers); base class lifecycle (PageTest/ContextTest) handles standard disposal automatically

🟡 Warning

• XPath locators or CSS locators when role/text/label locators are available
• Page.WaitForSelectorAsync() before ClickAsync() — redundant
• Tests that depend on execution order (not isolated)
• Multiple Page.GotoAsync() in the same test to different domains (use separate tests)
• Tests without assertions (navigation-only)
• Page.ScreenshotAsync() calls without try-catch (can hide assertion failures)
• Not using BrowserNewContextOptions to set consistent viewport/timezone/locale

🔵 Suggestion

• Missing data-testid attributes when CSS selectors are used repeatedly
• Tests longer than 30 lines without helper methods
• Duplicate locator chains across tests (extract to Page Object or helper)
• Using .Nth() when filter() would be clearer/stabler
• Overriding ContextOptions() without calling base.ContextOptions() for defaults