Make 3.10 sqlite3 tests run

[terryjreedy]

On my Windows 10, after fresh repository update and debug build, 3.10 sqlite3 tests do not run.
(3.11 and 3.12 are fine.) In 3.10, test_sqlite/ only contains test_dbapi.py

python -m test test_sqlite3 is OK after no tests run. (I though we made this an error.)
python -m test.test_sqlite3 fails because test_sqlite3/ is missing __main__.py, as well as __init__.py

In 3.11, test_sqlite3.__main__.py is

from test.test_sqlite3 import load_tests  # Needed for the "load tests" protocol.
import unittest

if __name__ == "__main__":
    unittest.main()

The comment seems not needed. The other 3.10 test.test_x directories all run and have variations of this. Some have from . import load_tests. Some have unittest.main('test.test_x') instead of a load_tests import. Most omit the redundant if-clause.

After adding __main__.py, tests still do not run because __init__.py is needed. I may try to do a PR tomorrow.

[terryjreedy]

I copied 3.11 test_sqlite3/__init__.py into the 3.10 directory.
With python -m test -v test_sqlite3, the loader runs but fails on line 47
def cx_limit(cx, category=sqlite.SQLITE_LIMIT_SQL_LENGTH, limit=128):
with an attribute error for SQLITE_LIMIT_SQL_LENGTH.

With the function commented out, python crashes with Windows fatal exception: access violation in test_connection_bad_reinit at line 572 , self.assertRaisesRegex(...) line 572. Before that, multiple tests failed, far more than need the commented out function.

(Reminder to self: changes on branch sql310.)

[erlend-aasland]

On my Windows 10, after fresh repository update and debug build, 3.10 sqlite3 tests do not run. (3.11 and 3.12 are fine.) In 3.10, test_sqlite/ only contains test_dbapi.py

There is no Lib/test/test_sqlite/ directory in the 3.10 branch. However, due to a backport failure (2229d34), there is a partial Lib/test/test_sqlite3/ directory. This needs to be removed from the 3.10 branch; the sqlite3 tests are found in Lib/sqlite3/test/ for the 3.10 branch and older.

In 3.11, test_sqlite3.__main__.py is [...]

The comment seems not needed.

It was added by Brett's request. I'd like to keep it there, as it explains the otherwise apparently unused import.

Most omit the redundant if-clause.

Tests can be run directly (./<test-path> on *nix) or via ./python -m test <test-name>, so please leave it as it is; it is needed.

[erlend-aasland]

FTR, sqlite3 tests run as they should in 3.10:

$ ./python.exe -m test test_sqlite -v | wc -l 
     369

[erlend-aasland]

Sorry, this may not be obvious, but the sqlite3 tests were moved in 3.11. For 3.10 and older, they all lived in Lib/sqlite3/test, and were invoked via Lib/test/test_sqlite.py (for example, python -m test test_sqlite). For 3.11, they live in Lib/test/test_sqlite3/, and they are now invoked using the correct module name (python -m test test_sqlite3).

Perhaps we should add an entry to the 3.11 What's New.