feat(react): Add a handled prop to ErrorBoundary (#14560)

The previous behaviour was to rely on the presence of the `fallback`
prop to decide if the error was considered handled or not. The new
property lets users explicitly choose what should the handled
status be. If omitted, the old behaviour is still applied.

Author: HHK1

packages/react/src/errorboundary.tsx

@@ -35,6 +35,12 @@ export type ErrorBoundaryProps = {
    *
    */
   fallback?: React.ReactElement | FallbackRender | undefined;
+  /**
+   * If set to `true` or `false`, the error `handled` property will be set to the given value.
+   * If unset, the default behaviour is to rely on the presence of the `fallback` prop to determine
+   * if the error was handled or not.
+   */
+  handled?: boolean | undefined;
   /** Called when the error boundary encounters an error */
   onError?: ((error: unknown, componentStack: string | undefined, eventId: string) => void) | undefined;
   /** Called on componentDidMount() */
@@ -107,7 +113,8 @@ class ErrorBoundary extends React.Component<ErrorBoundaryProps, ErrorBoundarySta
         beforeCapture(scope, error, passedInComponentStack);
       }
 
-      const eventId = captureReactException(error, errorInfo, { mechanism: { handled: !!this.props.fallback } });
+      const handled = this.props.handled != null ? this.props.handled : !!this.props.fallback;
+      const eventId = captureReactException(error, errorInfo, { mechanism: { handled } });
 
       if (onError) {
         onError(error, passedInComponentStack, eventId);

packages/react/test/errorboundary.test.tsx

@@ -4,7 +4,7 @@ import { fireEvent, render, screen } from '@testing-library/react';
 import * as React from 'react';
 import { useState } from 'react';
 
-import type { ErrorBoundaryProps } from '../src/errorboundary';
+import type { ErrorBoundaryProps, FallbackRender } from '../src/errorboundary';
 import { ErrorBoundary, UNKNOWN_COMPONENT, withErrorBoundary } from '../src/errorboundary';
 
 const mockCaptureException = jest.fn();
@@ -537,47 +537,47 @@ describe('ErrorBoundary', () => {
       expect(mockOnReset).toHaveBeenCalledTimes(1);
       expect(mockOnReset).toHaveBeenCalledWith(expect.any(Error), expect.any(String), expect.any(String));
     });
+    it.each`
+      fallback | handled      | expected
+      ${true}  | ${undefined} | ${true}
+      ${false} | ${undefined} | ${false}
+      ${true}  | ${false}     | ${false}
+      ${true}  | ${true}      | ${true}
+      ${false} | ${true}      | ${true}
+      ${false} | ${false}     | ${false}
+    `(
+      'sets `handled: $expected` when `handled` is $handled and `fallback` is $fallback',
+      async ({
+        fallback,
+        handled,
+        expected,
+      }: {
+        fallback: boolean;
+        handled: boolean | undefined;
+        expected: boolean;
+      }) => {
+        const fallbackComponent: FallbackRender | undefined = fallback
+          ? ({ resetError }) => <button data-testid="reset" onClick={resetError} />
+          : undefined;
+        render(
+          <TestApp handled={handled} fallback={fallbackComponent}>
+            <h1>children</h1>
+          </TestApp>,
+        );
 
-    it('sets `handled: true` when a fallback is provided', async () => {
-      render(
-        <TestApp fallback={({ resetError }) => <button data-testid="reset" onClick={resetError} />}>
-          <h1>children</h1>
-        </TestApp>,
-      );
-
-      expect(mockCaptureException).toHaveBeenCalledTimes(0);
-
-      const btn = screen.getByTestId('errorBtn');
-      fireEvent.click(btn);
-
-      expect(mockCaptureException).toHaveBeenCalledTimes(1);
-      expect(mockCaptureException).toHaveBeenLastCalledWith(expect.any(Object), {
-        captureContext: {
-          contexts: { react: { componentStack: expect.any(String) } },
-        },
-        mechanism: { handled: true },
-      });
-    });
-
-    it('sets `handled: false` when no fallback is provided', async () => {
-      render(
-        <TestApp>
-          <h1>children</h1>
-        </TestApp>,
-      );
-
-      expect(mockCaptureException).toHaveBeenCalledTimes(0);
-
-      const btn = screen.getByTestId('errorBtn');
-      fireEvent.click(btn);
+        expect(mockCaptureException).toHaveBeenCalledTimes(0);
 
-      expect(mockCaptureException).toHaveBeenCalledTimes(1);
-      expect(mockCaptureException).toHaveBeenLastCalledWith(expect.any(Object), {
-        captureContext: {
-          contexts: { react: { componentStack: expect.any(String) } },
-        },
-        mechanism: { handled: false },
-      });
-    });
+        const btn = screen.getByTestId('errorBtn');
+        fireEvent.click(btn);
+
+        expect(mockCaptureException).toHaveBeenCalledTimes(1);
+        expect(mockCaptureException).toHaveBeenLastCalledWith(expect.any(Object), {
+          captureContext: {
+            contexts: { react: { componentStack: expect.any(String) } },
+          },
+          mechanism: { handled: expected },
+        });
+      },
+    );
   });
 });