test_ctx_mgr_rollback_if_commit_failed assumes outdated SQLite locking behavior

Bug report

Bug description:

It's possible this is user error or similar, but I'm observing the following when compiling Python3.14.

The test test_ctx_mgr_rollback_if_commit_failed in Lib/test/test_sqlite3/test_dbapi.py seems to fail with modern SQLite versions because it assumes that a read-only transaction plus a user-defined function will block concurrent writers. The current test encodes a stronger assumption than SQLite provides, making it brittle across SQLite versions.

With recent SQLite releases (e.g. 3.47+), this assumption seems to be no longer valid, causing the parent process to successfully write to the database and the child process to fail with: sqlite3.OperationalError: user-defined function raised exception

This results in a false-negative test failure. The test contains the following assertion in the child process:

assert "database is locked" in input()

However, modern SQLite allows the parent to acquire a write lock in this scenario, so the parent correctly sends "no error" instead.

This causes the assertion to fail even though SQLite and the context manager are behaving correctly.

The proposed fix is relax the assertion to accept both valid outcomes:

line = input()
assert "database is locked" in line or "no error" in line

This preserves the original intent of verifying correct rollback behavior while remaining compatible with modern SQLite locking semantics.

Environment
• SQLite: 3.47.0
• Python: 3.14-dev / 3.12+
• Platform: Amz Linux 2023 (aarch64, but not architecture-specific)
• Compiler: Clang20

CPython versions tested on:

3.14

Operating systems tested on:

Linux

Linked PRs

• gh-143373
• gh-146575