gh-125593: Use colors to highlight error locations in tracebacks from exception group

Lib/test/test_traceback.py

@@ -4637,6 +4637,27 @@ def foo():
             f'{boldm}ZeroDivisionError{reset}: {magenta}division by zero{reset}']
         self.assertEqual(actual, expected)
 
+    def test_colorized_traceback_from_exception_group(self):
+        try:
+            exceptions = []
+            try:
+                1 / 0
+            except ZeroDivisionError as inner_exc:
+                exceptions.append(inner_exc)
+            raise ExceptionGroup("test", exceptions)
+        except Exception as e:
+            exc = traceback.TracebackException.from_exception(
+                e, capture_locals=True
+            )
+
+        actual = "".join(exc.format(colorize=True))
+        red = _colorize.ANSIColors.RED
+        boldr = _colorize.ANSIColors.BOLD_RED
+        reset = _colorize.ANSIColors.RESET
+
+        self.assertIn(f"{red}1 {reset+boldr}/{reset+red} 0{reset}", actual)
+        self.assertIn(f"{red}~~{reset+boldr}^{reset+red}~~{reset}", actual)
+
 
 if __name__ == "__main__":
     unittest.main()

Lib/traceback.py

@@ -1428,7 +1428,7 @@ def format(self, *, chain=True, _ctx=None, **kwargs):
                            f'+---------------- {title} ----------------\n')
                     _ctx.exception_group_depth += 1
                     if not truncated:
-                        yield from exc.exceptions[i].format(chain=chain, _ctx=_ctx)
+                        yield from exc.exceptions[i].format(chain=chain, _ctx=_ctx, colorize=colorize)
                     else:
                         remaining = num_excs - self.max_group_width
                         plural = 's' if remaining > 1 else ''

Misc/NEWS.d/next/Core and Builtins/2024-10-18-10-11-43.gh-issue-125593.Q97m3A.rst

@@ -0,0 +1 @@
+Use color to highlight error locations in traceback from exception group