gh-111726: Explicitly close database connections in sqlite3 doctests

Doc/library/sqlite3.rst

@@ -16,6 +16,8 @@
    src = sqlite3.connect(":memory:", isolation_level=None)
    dst = sqlite3.connect("tutorial.db", isolation_level=None)
    src.backup(dst)
+   src.close()
+   dst.close()
    del src, dst
 
 .. _sqlite3-intro:
@@ -221,6 +223,13 @@ creating a new cursor, then querying the database:
    >>> print(f'The highest scoring Monty Python movie is {title!r}, released in {year}')
    The highest scoring Monty Python movie is 'Monty Python and the Holy Grail', released in 1975
 
+.. testcleanup::
+
+   new_con.close()
+
+   import os
+   os.remove("tutorial.db")
+
 You've now created an SQLite database using the :mod:`!sqlite3` module,
 inserted data and retrieved values from it in multiple ways.
 
@@ -400,6 +409,8 @@ Module functions
    .. testsetup:: sqlite3.trace
 
       import sqlite3
+      import sys
+      old_hook = sys.unraisablehook
 
    .. doctest:: sqlite3.trace
 
@@ -412,12 +423,16 @@ Module functions
       >>> def debug(unraisable):
       ...     print(f"{unraisable.exc_value!r} in callback {unraisable.object.__name__}")
       ...     print(f"Error message: {unraisable.err_msg}")
-      >>> import sys
       >>> sys.unraisablehook = debug
       >>> cur = con.execute("SELECT 1")
       ZeroDivisionError('division by zero') in callback evil_trace
       Error message: None
 
+   .. testcleanup:: sqlite3.trace
+
+      con.close()
+      sys.unraisablehook = old_hook
+
 .. function:: register_adapter(type, adapter, /)
 
    Register an *adapter* :term:`callable` to adapt the Python type *type*
@@ -763,6 +778,10 @@ Connection objects
          ...     print(row)
          ('acbd18db4cc2f85cedef654fccc4a4d8',)
 
+      .. testcleanup::
+
+         con.close()
+
       .. versionchanged:: 3.13
 
          Passing *name*, *narg*, and *func* as keyword arguments is deprecated.
@@ -908,6 +927,7 @@ Connection objects
              FROM test ORDER BY x
          """)
          print(cur.fetchall())
+         con.close()
 
       .. testoutput::
          :hide:
@@ -1069,6 +1089,7 @@ Connection objects
          Added the ``sqlite3.enable_load_extension`` auditing event.
 
       .. testsetup:: sqlite3.loadext
+         :skipif: True
 
          import sqlite3
          con = sqlite3.connect(":memory:")
@@ -1098,14 +1119,17 @@ Connection objects
          for row in con.execute("SELECT rowid, name, ingredients FROM recipe WHERE name MATCH 'pie'"):
              print(row)
 
-         con.close()
-
       .. testoutput:: sqlite3.loadext
          :hide:
 
          (2, 'broccoli pie', 'broccoli cheese onions flour')
          (3, 'pumpkin pie', 'pumpkin sugar flour butter')
 
+      .. testcleanup::
+         :skipif: True
+
+         con.close()
+
    .. method:: load_extension(path, /, *, entrypoint=None)
 
       Load an SQLite extension from a shared library.
@@ -1161,6 +1185,11 @@ Connection objects
                  f.write('%s\n' % line)
          con.close()
 
+      .. testcleanup::
+
+         import os
+         os.remove('dump.sql')
+
       .. seealso::
 
          :ref:`sqlite3-howto-encoding`
@@ -1223,13 +1252,25 @@ Connection objects
 
          Copied 0 of 0 pages...
 
+      .. testcleanup::
+
+         import os
+         os.remove('backup.db')
+
       Example 2, copy an existing database into a transient copy:
 
       .. testcode::
 
          src = sqlite3.connect('example.db')
          dst = sqlite3.connect(':memory:')
          src.backup(dst)
+         dst.close()
+         src.close()
+
+      .. testcleanup::
+
+         import os
+         os.remove('example.db')
 
       .. versionadded:: 3.7
 
@@ -1264,6 +1305,10 @@ Connection objects
          >>> con.getlimit(sqlite3.SQLITE_LIMIT_SQL_LENGTH)
          1000000000
 
+      .. testcleanup:: sqlite3.limits
+
+         con.close()
+
       .. versionadded:: 3.11
 
 
@@ -1577,6 +1622,10 @@ Cursor objects
          # cur is an sqlite3.Cursor object
          cur.executemany("INSERT INTO data VALUES(?)", rows)
 
+      .. testcleanup:: sqlite3.cursor
+
+         con.close()
+
       .. note::
 
          Any resulting rows are discarded,
@@ -1683,6 +1732,10 @@ Cursor objects
          >>> cur.connection == con
          True
 
+      .. testcleanup::
+
+         con.close()
+
    .. attribute:: description
 
       Read-only attribute that provides the column names of the last query. To
@@ -1802,6 +1855,7 @@ Blob objects
           greeting = blob.read()
 
       print(greeting)  # outputs "b'Hello, world!'"
+      con.close()
 
    .. testoutput::
       :hide:
@@ -2114,6 +2168,7 @@ Here's an example of both styles:
    params = (1972,)
    cur.execute("SELECT * FROM lang WHERE first_appeared = ?", params)
    print(cur.fetchall())
+   con.close()
 
 .. testoutput::
    :hide:
@@ -2172,6 +2227,7 @@ The object passed to *protocol* will be of type :class:`PrepareProtocol`.
 
    cur.execute("SELECT ?", (Point(4.0, -3.2),))
    print(cur.fetchone()[0])
+   con.close()
 
 .. testoutput::
    :hide:
@@ -2202,6 +2258,7 @@ This function can then be registered using :func:`register_adapter`.
 
    cur.execute("SELECT ?", (Point(1.0, 2.5),))
    print(cur.fetchone()[0])
+   con.close()
 
 .. testoutput::
    :hide:
@@ -2286,6 +2343,8 @@ The following example illustrates the implicit and explicit approaches:
    cur.execute("INSERT INTO test(p) VALUES(?)", (p,))
    cur.execute('SELECT p AS "p [point]" FROM test')
    print("with column names:", cur.fetchone()[0])
+   cur.close()
+   con.close()
 
 .. testoutput::
    :hide:
@@ -2492,6 +2551,8 @@ Some useful URI tricks include:
    res = con2.execute("SELECT data FROM shared")
    assert res.fetchone() == (28,)
 
+   con1.close()
+   con2.close()
 
 More information about this feature, including a list of parameters,
 can be found in the `SQLite URI documentation`_.
@@ -2524,6 +2585,10 @@ assign it to the :attr:`!row_factory` attribute:
    >>> con = sqlite3.connect(":memory:")
    >>> con.row_factory = sqlite3.Row
 
+.. testcleanup::
+
+   con.close()
+
 Queries now return :class:`!Row` objects:
 
 .. doctest::
@@ -2539,6 +2604,10 @@ Queries now return :class:`!Row` objects:
    >>> row["RADIUS"]  # Column names are case-insensitive.
    6378
 
+.. testcleanup::
+
+   con.close()
+
 .. note::
 
     The ``FROM`` clause can be omitted in the ``SELECT`` statement, as in the
@@ -2565,6 +2634,10 @@ Using it, queries now return a :class:`!dict` instead of a :class:`!tuple`:
    ...     print(row)
    {'a': 1, 'b': 2}
 
+.. testcleanup::
+
+   con.close()
+
 The following row factory returns a :term:`named tuple`:
 
 .. testcode::
@@ -2591,6 +2664,10 @@ The following row factory returns a :term:`named tuple`:
    >>> row.b   # Attribute access.
    2
 
+.. testcleanup::
+
+   con.close()
+
 With some adjustments, the above recipe can be adapted to use a
 :class:`~dataclasses.dataclass`, or any other custom class,
 instead of a :class:`~collections.namedtuple`.