docs: Add note about swallowing of custom reporter errors (#37915)

Author: cpAdm

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

@@ -87,6 +87,11 @@ and [`method: Reporter.onError`] is called when something went wrong outside of
 
 If your custom reporter does not print anything to the terminal, implement [`method: Reporter.printsToStdio`] and return `false`. This way, Playwright will use one of the standard terminal reporters in addition to your custom reporter to enhance user experience.
 
+**Reporter errors**
+
+Playwright will swallow any errors thrown in your custom reporter methods. If you need to detect or fail on reporter
+errors, you must wrap and handle them yourself.
+
 **Merged report API notes**
 
 When merging multiple [`blob`](../test-reporters#blob-reporter) reports via [`merge-reports`](../test-sharding#merge-reports-cli) CLI

packages/playwright/types/testReporter.d.ts

@@ -127,6 +127,11 @@ export interface FullResult {
  * `false`. This way, Playwright will use one of the standard terminal reporters in addition to your custom reporter
  * to enhance user experience.
  *
+ * **Reporter errors**
+ *
+ * Playwright will swallow any errors thrown in your custom reporter methods. If you need to detect or fail on
+ * reporter errors, you must wrap and handle them yourself.
+ *
  * **Merged report API notes**
  *
  * When merging multiple [`blob`](https://playwright.dev/docs/test-reporters#blob-reporter) reports via