gh-137288: Fix bug where boolean expressions are not associated with the correct exception handler

Author: iritkatriel

Lib/test/test_compile.py

@@ -1723,6 +1723,21 @@ def test_compound(self):
         self.assertIs(res, v[3])
         self.assertEqual([e.called for e in v], [1, 1, 0, 1, 0])
 
+    def test_exception(self):
+        # See gh-137288
+        class Foo:
+            def __bool__(self):
+                raise NotImplementedError()
+
+        a = Foo()
+        b = Foo()
+
+        with self.assertRaises(NotImplementedError):
+            bool(a)
+
+        with self.assertRaises(NotImplementedError):
+            c = a or b
+
 @requires_debug_ranges()
 class TestSourcePositions(unittest.TestCase):
     # Ensure that compiled code snippets have correct line and column numbers

Misc/NEWS.d/next/Core_and_Builtins/2025-08-01-18-54-31.gh-issue-137288.FhE7ku.rst

@@ -0,0 +1,2 @@
+Fix bug where some bytecode instructions of a boolean expression are not
+associated with the correct exception handler.

Python/flowgraph.c

@@ -3477,13 +3477,15 @@ convert_pseudo_conditional_jumps(cfg_builder *g)
                             .i_oparg = 1,
                             .i_loc = loc,
                             .i_target = NULL,
+                            .i_except = instr->i_except,
                 };
                 RETURN_IF_ERROR(basicblock_insert_instruction(b, i++, &copy));
                 cfg_instr to_bool = {
                             .i_opcode = TO_BOOL,
                             .i_oparg = 0,
                             .i_loc = loc,
                             .i_target = NULL,
+                            .i_except = instr->i_except,
                 };
                 RETURN_IF_ERROR(basicblock_insert_instruction(b, i++, &to_bool));
             }
@@ -3726,13 +3728,15 @@ insert_prefix_instructions(_PyCompile_CodeUnitMetadata *umd, basicblock *entrybl
             .i_oparg = 0,
             .i_loc = loc,
             .i_target = NULL,
+            .i_except = NULL,
         };
         RETURN_IF_ERROR(basicblock_insert_instruction(entryblock, 0, &make_gen));
         cfg_instr pop_top = {
             .i_opcode = POP_TOP,
             .i_oparg = 0,
             .i_loc = loc,
             .i_target = NULL,
+            .i_except = NULL,
         };
         RETURN_IF_ERROR(basicblock_insert_instruction(entryblock, 1, &pop_top));
     }
@@ -3763,6 +3767,7 @@ insert_prefix_instructions(_PyCompile_CodeUnitMetadata *umd, basicblock *entrybl
                 .i_oparg = oldindex,
                 .i_loc = NO_LOCATION,
                 .i_target = NULL,
+                .i_except = NULL,
             };
             if (basicblock_insert_instruction(entryblock, ncellsused, &make_cell) < 0) {
                 PyMem_RawFree(sorted);
@@ -3779,6 +3784,7 @@ insert_prefix_instructions(_PyCompile_CodeUnitMetadata *umd, basicblock *entrybl
             .i_oparg = nfreevars,
             .i_loc = NO_LOCATION,
             .i_target = NULL,
+            .i_except = NULL,
         };
         RETURN_IF_ERROR(basicblock_insert_instruction(entryblock, 0, &copy_frees));
     }