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FA-5251 / Exception flow / Open access

Exception chaining metadata: Reraises the original exception instead of the requested wrapper · case 01

Reraises the original exception instead of the requested wrapper and changes the required Python-language result.

Verified by executionVariant 1 · 4 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Reraises the original exception instead of the requested wrapper. The executable reproducer isolates this operation from the rest of the contract.

VERIFIED REPAIR

Wrap ValueError in RuntimeError with implicit, explicit, or from-None chaining. Return [error type,cause type or None,context type or None,suppress-context flag]. Suppressing displayed context does not erase __context__.

Unsuccessful approach: The alternative still fails because it raises the wrapper without its requested explicit cause.

Case contract

Wrap ValueError in RuntimeError with implicit, explicit, or from-None chaining. Return [error type,cause type or None,context type or None,suppress-context flag]. Suppressing displayed context does not erase __context__. Inputs use the finite Python types shown in the fixtures. An error string denotes the specified caught exception, not an unhandled process failure.

Why this case matters

Runs Python standard-library language operations in a deterministic local reproducer. Literal expected answers are authored independently. Related defects share an evaluation group to avoid benchmark split leakage.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(mode):
    try:
        try:
            raise ValueError('original')
        except ValueError as original:
            error=RuntimeError('wrapper')
            if mode=='explicit':
                raise
            elif mode=='suppressed':
                raise
            else:
                raise
    except BaseException as caught:
        pass
        return [type(caught).__name__, None if caught.__cause__ is None else type(caught.__cause__).__name__, None if caught.__context__ is None else type(caught.__context__).__name__, caught.__suppress_context__]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('explicit cause', solve('explicit'), ['RuntimeError', 'ValueError', 'ValueError', True])
check('suppressed display', solve('suppressed'), ['RuntimeError', None, 'ValueError', True])
check('implicit context', solve('implicit'), ['RuntimeError', None, 'ValueError', False])
check('default path remains implicit', solve('other'), ['RuntimeError', None, 'ValueError', False])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
explicit cause['ValueError', None, None, False]['RuntimeError', 'ValueError', 'ValueError', True]Failed
suppressed display['ValueError', None, None, False]['RuntimeError', None, 'ValueError', True]Failed
implicit context['ValueError', None, None, False]['RuntimeError', None, 'ValueError', False]Failed
default path remains implicit['ValueError', None, None, False]['RuntimeError', None, 'ValueError', False]Failed

SHA-256 / b62386b5d839b8fd1ef2f6195e26d77d2cb23ebc6b4b89311f39f049e3a920cc

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(mode):
    try:
        try:
            raise ValueError('original')
        except ValueError as original:
            error=RuntimeError('wrapper')
            if mode=='explicit':
                raise error
            elif mode=='suppressed':
                raise error from None
            else:
                raise error
    except BaseException as caught:
        pass
        return [type(caught).__name__, None if caught.__cause__ is None else type(caught.__cause__).__name__, None if caught.__context__ is None else type(caught.__context__).__name__, caught.__suppress_context__]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('explicit cause', solve('explicit'), ['RuntimeError', 'ValueError', 'ValueError', True])
check('suppressed display', solve('suppressed'), ['RuntimeError', None, 'ValueError', True])
check('implicit context', solve('implicit'), ['RuntimeError', None, 'ValueError', False])
check('default path remains implicit', solve('other'), ['RuntimeError', None, 'ValueError', False])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
explicit cause['RuntimeError', None, 'ValueError', False]['RuntimeError', 'ValueError', 'ValueError', True]Failed
suppressed display['RuntimeError', None, 'ValueError', True]['RuntimeError', None, 'ValueError', True]Passed
implicit context['RuntimeError', None, 'ValueError', False]['RuntimeError', None, 'ValueError', False]Passed
default path remains implicit['RuntimeError', None, 'ValueError', False]['RuntimeError', None, 'ValueError', False]Passed

SHA-256 / a8b189773a9846614a97a77a4623d5fac339516dde46bb430efc4fdf6f5f14c7

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(mode):
    try:
        try:
            raise ValueError('original')
        except ValueError as original:
            error=RuntimeError('wrapper')
            if mode=='explicit':
                raise error from original
            elif mode=='suppressed':
                raise error from None
            else:
                raise error
    except BaseException as caught:
        pass
        return [type(caught).__name__, None if caught.__cause__ is None else type(caught.__cause__).__name__, None if caught.__context__ is None else type(caught.__context__).__name__, caught.__suppress_context__]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
check('explicit cause', solve('explicit'), ['RuntimeError', 'ValueError', 'ValueError', True])
check('suppressed display', solve('suppressed'), ['RuntimeError', None, 'ValueError', True])
check('implicit context', solve('implicit'), ['RuntimeError', None, 'ValueError', False])
check('default path remains implicit', solve('other'), ['RuntimeError', None, 'ValueError', False])
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
explicit cause['RuntimeError', 'ValueError', 'ValueError', True]['RuntimeError', 'ValueError', 'ValueError', True]Passed
suppressed display['RuntimeError', None, 'ValueError', True]['RuntimeError', None, 'ValueError', True]Passed
implicit context['RuntimeError', None, 'ValueError', False]['RuntimeError', None, 'ValueError', False]Passed
default path remains implicit['RuntimeError', None, 'ValueError', False]['RuntimeError', None, 'ValueError', False]Passed

SHA-256 / f298b5850e85d1c41cef21ebfc85bc463d87ca117fcc39239a37d1937c35333e

Verification & scope

This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:37:47.624319+00:00.

Case digest / 56bf3df0662535c3d3df08a5ffe17f2ad6ca6b6e89aa423967c98cc26acaba46