Revert "gh-139551: add support for BaseExceptionGroup in IDLE (GH-139563)"

This reverts commit 1e79bf6.

Author: prakashsellathurai

Lib/idlelib/idle_test/test_run.py

@@ -82,99 +82,6 @@ def test_get_multiple_message(self, mock):
                         subtests += 1
         self.assertEqual(subtests, len(data2))  # All subtests ran?
 
-    def _capture_exception(self):
-        """Call run.print_exception() and return its stderr output."""
-        with captured_stderr() as output:
-            with mock.patch.object(run, 'cleanup_traceback') as ct:
-                ct.side_effect = lambda t, e: t
-                run.print_exception()
-        return output.getvalue()
-
-    @force_not_colorized
-    def test_print_exception_group_nested(self):
-        try:
-            try:
-                raise ExceptionGroup('inner', [ValueError('v1')])
-            except ExceptionGroup as inner:
-                raise ExceptionGroup('outer', [inner, TypeError('t1')])
-        except ExceptionGroup:
-            tb = self._capture_exception()
-
-        self.assertIn('ExceptionGroup: outer (2 sub-exceptions)', tb)
-        self.assertIn('ExceptionGroup: inner', tb)
-        self.assertIn('ValueError: v1', tb)
-        self.assertIn('TypeError: t1', tb)
-        # Verify tree structure characters.
-        self.assertIn('+-+---------------- 1 ----------------', tb)
-        self.assertIn('+---------------- 2 ----------------', tb)
-        self.assertIn('+------------------------------------', tb)
-
-    @force_not_colorized
-    def test_print_exception_group_chaining(self):
-        # __cause__ on a sub-exception exercises the prefixed
-        # chaining-message path (margin chars on separator lines).
-        sub = TypeError('t1')
-        sub.__cause__ = ValueError('original')
-        try:
-            raise ExceptionGroup('eg1', [sub])
-        except ExceptionGroup:
-            tb = self._capture_exception()
-        self.assertIn('ValueError: original', tb)
-        self.assertIn('| The above exception was the direct cause', tb)
-        self.assertIn('ExceptionGroup: eg1', tb)
-
-        # __context__ (implicit chaining) on a sub-exception.
-        sub = TypeError('t2')
-        sub.__context__ = ValueError('first')
-        try:
-            raise ExceptionGroup('eg2', [sub])
-        except ExceptionGroup:
-            tb = self._capture_exception()
-        self.assertIn('ValueError: first', tb)
-        self.assertIn('| During handling of the above exception', tb)
-        self.assertIn('ExceptionGroup: eg2', tb)
-
-    @force_not_colorized
-    def test_print_exception_group_seen(self):
-        shared = ValueError('shared')
-        try:
-            raise ExceptionGroup('eg', [shared, shared])
-        except ExceptionGroup:
-            tb = self._capture_exception()
-
-        self.assertIn('ValueError: shared', tb)
-        self.assertIn('<exception ValueError has printed>', tb)
-
-    @force_not_colorized
-    def test_print_exception_group_max_width(self):
-        excs = [ValueError(f'v{i}') for i in range(20)]
-        try:
-            raise ExceptionGroup('eg', excs)
-        except ExceptionGroup:
-            tb = self._capture_exception()
-
-        self.assertIn('+---------------- 15 ----------------', tb)
-        self.assertIn('+---------------- ... ----------------', tb)
-        self.assertIn('and 5 more exceptions', tb)
-        self.assertNotIn('+---------------- 16 ----------------', tb)
-
-    @force_not_colorized
-    def test_print_exception_group_max_depth(self):
-        def make_nested(depth):
-            if depth == 0:
-                return ValueError('leaf')
-            return ExceptionGroup(f'level{depth}',
-                                  [make_nested(depth - 1)])
-
-        try:
-            raise make_nested(15)
-        except ExceptionGroup:
-            tb = self._capture_exception()
-
-        self.assertIn('... (max_group_depth is 10)', tb)
-        self.assertIn('ExceptionGroup: level15', tb)
-        self.assertNotIn('ValueError: leaf', tb)
-
 # StdioFile tests.
 
 class S(str):

Lib/idlelib/run.py

@@ -249,94 +249,31 @@ def print_exception():
     sys.last_type, sys.last_value, sys.last_traceback = excinfo
     sys.last_exc = val
     seen = set()
-    exclude = ("run.py", "rpc.py", "threading.py", "queue.py",
-               "debugger_r.py", "bdb.py")
-    max_group_width = 15
-    max_group_depth = 10
-    group_depth = 0
-
-    def print_exc_group(typ, exc, tb, prefix=""):
-        nonlocal group_depth
-        group_depth += 1
-        prefix2 = prefix or "  "
-        if group_depth > max_group_depth:
-            print(f"{prefix2}| ... (max_group_depth is {max_group_depth})",
-                  file=efile)
-            group_depth -= 1
-            return
-        if tb:
-            if not prefix:
-                print("  + Exception Group Traceback (most recent call last):", file=efile)
-            else:
-                print(f"{prefix}| Exception Group Traceback (most recent call last):", file=efile)
-            tbe = traceback.extract_tb(tb)
-            cleanup_traceback(tbe, exclude)
-            for line in traceback.format_list(tbe):
-                for subline in line.rstrip().splitlines():
-                    print(f"{prefix2}| {subline}", file=efile)
-        lines = get_message_lines(typ, exc, tb)
-        for line in lines:
-            print(f"{prefix2}| {line}", end="", file=efile)
-        num_excs = len(exc.exceptions)
-        if num_excs <= max_group_width:
-            n = num_excs
-        else:
-            n = max_group_width + 1
-        for i, sub in enumerate(exc.exceptions[:n], 1):
-            truncated = (i > max_group_width)
-            first_line_pre = "+-" if i == 1 else "  "
-            title = str(i) if not truncated else '...'
-            print(f"{prefix2}{first_line_pre}+---------------- {title} ----------------", file=efile)
-            if truncated:
-                remaining = num_excs - max_group_width
-                plural = 's' if remaining > 1 else ''
-                print(f"{prefix2}  | and {remaining} more exception{plural}",
-                      file=efile)
-                need_print_underline = True
-            elif id(sub) not in seen:
-                if not prefix:
-                    print_exc(type(sub), sub, sub.__traceback__, "    ")
-                else:
-                    print_exc(type(sub), sub, sub.__traceback__, prefix + "  ")
-                need_print_underline = not isinstance(sub, BaseExceptionGroup)
-            else:
-                print(f"{prefix2}  | <exception {type(sub).__name__} has printed>", file=efile)
-                need_print_underline = True
-            if need_print_underline and i == n:
-                print(f"{prefix2}  +------------------------------------", file=efile)
-        group_depth -= 1
 
-    def print_exc(typ, exc, tb, prefix=""):
+    def print_exc(typ, exc, tb):
         seen.add(id(exc))
         context = exc.__context__
         cause = exc.__cause__
-        prefix2 = f"{prefix}| " if prefix else ""
         if cause is not None and id(cause) not in seen:
-            print_exc(type(cause), cause, cause.__traceback__, prefix)
-            print(f"{prefix2}\n{prefix2}The above exception was the direct cause "
-                  f"of the following exception:\n{prefix2}", file=efile)
+            print_exc(type(cause), cause, cause.__traceback__)
+            print("\nThe above exception was the direct cause "
+                  "of the following exception:\n", file=efile)
         elif (context is not None and
               not exc.__suppress_context__ and
               id(context) not in seen):
-            print_exc(type(context), context, context.__traceback__, prefix)
-            print(f"{prefix2}\n{prefix2}During handling of the above exception, "
-                  f"another exception occurred:\n{prefix2}", file=efile)
-        if isinstance(exc, BaseExceptionGroup):
-            print_exc_group(typ, exc, tb, prefix=prefix)
-        else:
-            if tb:
-                print(f"{prefix2}Traceback (most recent call last):", file=efile)
-                tbe = traceback.extract_tb(tb)
-                cleanup_traceback(tbe, exclude)
-                if prefix:
-                    for line in traceback.format_list(tbe):
-                        for subline in line.rstrip().splitlines():
-                            print(f"{prefix}| {subline}", file=efile)
-                else:
-                    traceback.print_list(tbe, file=efile)
-            lines = get_message_lines(typ, exc, tb)
-            for line in lines:
-                print(f"{prefix2}{line}", end="", file=efile)
+            print_exc(type(context), context, context.__traceback__)
+            print("\nDuring handling of the above exception, "
+                  "another exception occurred:\n", file=efile)
+        if tb:
+            tbe = traceback.extract_tb(tb)
+            print('Traceback (most recent call last):', file=efile)
+            exclude = ("run.py", "rpc.py", "threading.py", "queue.py",
+                       "debugger_r.py", "bdb.py")
+            cleanup_traceback(tbe, exclude)
+            traceback.print_list(tbe, file=efile)
+        lines = get_message_lines(typ, exc, tb)
+        for line in lines:
+            print(line, end='', file=efile)
 
     print_exc(typ, val, tb)