TST/CLN: Ensure sqlite memory connections are closed (#49154)

* TST/CLN: Use fixtures for TestXSQLite

* More sqlite closing

Author: mroeschke

pandas/tests/io/test_sql.py

@@ -18,6 +18,7 @@
 """
 from __future__ import annotations
 
+import contextlib
 from contextlib import closing
 import csv
 from datetime import (
@@ -456,8 +457,9 @@ def sqlite_iris_conn(sqlite_iris_engine):
 
 @pytest.fixture
 def sqlite_buildin():
-    with sqlite3.connect(":memory:") as conn:
-        yield conn
+    with contextlib.closing(sqlite3.connect(":memory:")) as closing_conn:
+        with closing_conn as conn:
+            yield conn
 
 
 @pytest.fixture
@@ -1561,9 +1563,12 @@ def __init__(self, *args, **kwargs) -> None:
             def __getattr__(self, name):
                 return getattr(self.conn, name)
 
-        conn = MockSqliteConnection(":memory:")
-        with tm.assert_produces_warning(UserWarning):
-            sql.read_sql("SELECT 1", conn)
+            def close(self):
+                self.conn.close()
+
+        with contextlib.closing(MockSqliteConnection(":memory:")) as conn:
+            with tm.assert_produces_warning(UserWarning):
+                sql.read_sql("SELECT 1", conn)
 
     def test_read_sql_delegate(self):
         iris_frame1 = sql.read_sql_query("SELECT * FROM iris", self.conn)
@@ -1945,7 +1950,7 @@ def test_datetime_date(self):
         # comes back as datetime64
         tm.assert_series_equal(result, expected)
 
-    def test_datetime_time(self):
+    def test_datetime_time(self, sqlite_buildin):
         # test support for datetime.time
         df = DataFrame([time(9, 0, 0), time(9, 1, 30)], columns=["a"])
         assert df.to_sql("test_time", self.conn, index=False) == 2
@@ -1954,7 +1959,7 @@ def test_datetime_time(self):
 
         # GH8341
         # first, use the fallback to have the sqlite adapter put in place
-        sqlite_conn = TestSQLiteFallback.connect()
+        sqlite_conn = sqlite_buildin
         assert sql.to_sql(df, "test_time2", sqlite_conn, index=False) == 2
         res = sql.read_sql_query("SELECT * FROM test_time2", sqlite_conn)
         ref = df.applymap(lambda _: _.strftime("%H:%M:%S.%f"))
@@ -2762,21 +2767,17 @@ def tquery(query, con=None):
 
 
 class TestXSQLite:
-    def setup_method(self):
-        self.conn = sqlite3.connect(":memory:")
-
-    def teardown_method(self):
-        self.conn.close()
-
-    def drop_table(self, table_name):
-        cur = self.conn.cursor()
+    def drop_table(self, table_name, conn):
+        cur = conn.cursor()
         cur.execute(f"DROP TABLE IF EXISTS {sql._get_valid_sqlite_name(table_name)}")
-        self.conn.commit()
+        conn.commit()
 
-    def test_basic(self):
+    def test_basic(self, sqlite_buildin):
         frame = tm.makeTimeDataFrame()
-        assert sql.to_sql(frame, name="test_table", con=self.conn, index=False) == 30
-        result = sql.read_sql("select * from test_table", self.conn)
+        assert (
+            sql.to_sql(frame, name="test_table", con=sqlite_buildin, index=False) == 30
+        )
+        result = sql.read_sql("select * from test_table", sqlite_buildin)
 
         # HACK! Change this once indexes are handled properly.
         result.index = frame.index
@@ -2788,47 +2789,52 @@ def test_basic(self):
         frame2 = frame.copy()
         new_idx = Index(np.arange(len(frame2))) + 10
         frame2["Idx"] = new_idx.copy()
-        assert sql.to_sql(frame2, name="test_table2", con=self.conn, index=False) == 30
-        result = sql.read_sql("select * from test_table2", self.conn, index_col="Idx")
+        assert (
+            sql.to_sql(frame2, name="test_table2", con=sqlite_buildin, index=False)
+            == 30
+        )
+        result = sql.read_sql(
+            "select * from test_table2", sqlite_buildin, index_col="Idx"
+        )
         expected = frame.copy()
         expected.index = new_idx
         expected.index.name = "Idx"
         tm.assert_frame_equal(expected, result)
 
-    def test_write_row_by_row(self):
+    def test_write_row_by_row(self, sqlite_buildin):
         frame = tm.makeTimeDataFrame()
         frame.iloc[0, 0] = np.nan
         create_sql = sql.get_schema(frame, "test")
-        cur = self.conn.cursor()
+        cur = sqlite_buildin.cursor()
         cur.execute(create_sql)
 
         ins = "INSERT INTO test VALUES (%s, %s, %s, %s)"
         for _, row in frame.iterrows():
             fmt_sql = format_query(ins, *row)
-            tquery(fmt_sql, con=self.conn)
+            tquery(fmt_sql, con=sqlite_buildin)
 
-        self.conn.commit()
+        sqlite_buildin.commit()
 
-        result = sql.read_sql("select * from test", con=self.conn)
+        result = sql.read_sql("select * from test", con=sqlite_buildin)
         result.index = frame.index
         tm.assert_frame_equal(result, frame, rtol=1e-3)
 
-    def test_execute(self):
+    def test_execute(self, sqlite_buildin):
         frame = tm.makeTimeDataFrame()
         create_sql = sql.get_schema(frame, "test")
-        cur = self.conn.cursor()
+        cur = sqlite_buildin.cursor()
         cur.execute(create_sql)
         ins = "INSERT INTO test VALUES (?, ?, ?, ?)"
 
         row = frame.iloc[0]
-        sql.execute(ins, self.conn, params=tuple(row))
-        self.conn.commit()
+        sql.execute(ins, sqlite_buildin, params=tuple(row))
+        sqlite_buildin.commit()
 
-        result = sql.read_sql("select * from test", self.conn)
+        result = sql.read_sql("select * from test", sqlite_buildin)
         result.index = frame.index[:1]
         tm.assert_frame_equal(result, frame[:1])
 
-    def test_schema(self):
+    def test_schema(self, sqlite_buildin):
         frame = tm.makeTimeDataFrame()
         create_sql = sql.get_schema(frame, "test")
         lines = create_sql.splitlines()
@@ -2840,10 +2846,10 @@ def test_schema(self):
         create_sql = sql.get_schema(frame, "test", keys=["A", "B"])
         lines = create_sql.splitlines()
         assert 'PRIMARY KEY ("A", "B")' in create_sql
-        cur = self.conn.cursor()
+        cur = sqlite_buildin.cursor()
         cur.execute(create_sql)
 
-    def test_execute_fail(self):
+    def test_execute_fail(self, sqlite_buildin):
         create_sql = """
         CREATE TABLE test
         (
@@ -2853,14 +2859,14 @@ def test_execute_fail(self):
         PRIMARY KEY (a, b)
         );
         """
-        cur = self.conn.cursor()
+        cur = sqlite_buildin.cursor()
         cur.execute(create_sql)
 
-        sql.execute('INSERT INTO test VALUES("foo", "bar", 1.234)', self.conn)
-        sql.execute('INSERT INTO test VALUES("foo", "baz", 2.567)', self.conn)
+        sql.execute('INSERT INTO test VALUES("foo", "bar", 1.234)', sqlite_buildin)
+        sql.execute('INSERT INTO test VALUES("foo", "baz", 2.567)', sqlite_buildin)
 
         with pytest.raises(sql.DatabaseError, match="Execution failed on sql"):
-            sql.execute('INSERT INTO test VALUES("foo", "bar", 7)', self.conn)
+            sql.execute('INSERT INTO test VALUES("foo", "bar", 7)', sqlite_buildin)
 
     def test_execute_closed_connection(self):
         create_sql = """
@@ -2872,36 +2878,36 @@ def test_execute_closed_connection(self):
         PRIMARY KEY (a, b)
         );
         """
-        cur = self.conn.cursor()
-        cur.execute(create_sql)
+        with contextlib.closing(sqlite3.connect(":memory:")) as conn:
+            cur = conn.cursor()
+            cur.execute(create_sql)
 
-        sql.execute('INSERT INTO test VALUES("foo", "bar", 1.234)', self.conn)
-        self.conn.close()
+            sql.execute('INSERT INTO test VALUES("foo", "bar", 1.234)', conn)
 
         msg = "Cannot operate on a closed database."
         with pytest.raises(sqlite3.ProgrammingError, match=msg):
-            tquery("select * from test", con=self.conn)
+            tquery("select * from test", con=conn)
 
-    def test_keyword_as_column_names(self):
+    def test_keyword_as_column_names(self, sqlite_buildin):
         df = DataFrame({"From": np.ones(5)})
-        assert sql.to_sql(df, con=self.conn, name="testkeywords", index=False) == 5
+        assert sql.to_sql(df, con=sqlite_buildin, name="testkeywords", index=False) == 5
 
-    def test_onecolumn_of_integer(self):
+    def test_onecolumn_of_integer(self, sqlite_buildin):
         # GH 3628
         # a column_of_integers dataframe should transfer well to sql
 
         mono_df = DataFrame([1, 2], columns=["c0"])
-        assert sql.to_sql(mono_df, con=self.conn, name="mono_df", index=False) == 2
+        assert sql.to_sql(mono_df, con=sqlite_buildin, name="mono_df", index=False) == 2
         # computing the sum via sql
-        con_x = self.conn
+        con_x = sqlite_buildin
         the_sum = sum(my_c0[0] for my_c0 in con_x.execute("select * from mono_df"))
         # it should not fail, and gives 3 ( Issue #3628 )
         assert the_sum == 3
 
         result = sql.read_sql("select * from mono_df", con_x)
         tm.assert_frame_equal(result, mono_df)
 
-    def test_if_exists(self):
+    def test_if_exists(self, sqlite_buildin):
         df_if_exists_1 = DataFrame({"col1": [1, 2], "col2": ["A", "B"]})
         df_if_exists_2 = DataFrame({"col1": [3, 4, 5], "col2": ["C", "D", "E"]})
         table_name = "table_if_exists"
@@ -2911,70 +2917,73 @@ def test_if_exists(self):
         with pytest.raises(ValueError, match=msg):
             sql.to_sql(
                 frame=df_if_exists_1,
-                con=self.conn,
+                con=sqlite_buildin,
                 name=table_name,
                 if_exists="notvalidvalue",
             )
-        self.drop_table(table_name)
+        self.drop_table(table_name, sqlite_buildin)
 
         # test if_exists='fail'
         sql.to_sql(
-            frame=df_if_exists_1, con=self.conn, name=table_name, if_exists="fail"
+            frame=df_if_exists_1, con=sqlite_buildin, name=table_name, if_exists="fail"
         )
         msg = "Table 'table_if_exists' already exists"
         with pytest.raises(ValueError, match=msg):
             sql.to_sql(
-                frame=df_if_exists_1, con=self.conn, name=table_name, if_exists="fail"
+                frame=df_if_exists_1,
+                con=sqlite_buildin,
+                name=table_name,
+                if_exists="fail",
             )
         # test if_exists='replace'
         sql.to_sql(
             frame=df_if_exists_1,
-            con=self.conn,
+            con=sqlite_buildin,
             name=table_name,
             if_exists="replace",
             index=False,
         )
-        assert tquery(sql_select, con=self.conn) == [(1, "A"), (2, "B")]
+        assert tquery(sql_select, con=sqlite_buildin) == [(1, "A"), (2, "B")]
         assert (
             sql.to_sql(
                 frame=df_if_exists_2,
-                con=self.conn,
+                con=sqlite_buildin,
                 name=table_name,
                 if_exists="replace",
                 index=False,
             )
             == 3
         )
-        assert tquery(sql_select, con=self.conn) == [(3, "C"), (4, "D"), (5, "E")]
-        self.drop_table(table_name)
+        assert tquery(sql_select, con=sqlite_buildin) == [(3, "C"), (4, "D"), (5, "E")]
+        self.drop_table(table_name, sqlite_buildin)
 
         # test if_exists='append'
         assert (
             sql.to_sql(
                 frame=df_if_exists_1,
-                con=self.conn,
+                con=sqlite_buildin,
                 name=table_name,
                 if_exists="fail",
                 index=False,
             )
             == 2
         )
-        assert tquery(sql_select, con=self.conn) == [(1, "A"), (2, "B")]
+        assert tquery(sql_select, con=sqlite_buildin) == [(1, "A"), (2, "B")]
         assert (
             sql.to_sql(
                 frame=df_if_exists_2,
-                con=self.conn,
+                con=sqlite_buildin,
                 name=table_name,
                 if_exists="append",
                 index=False,
             )
             == 3
         )
-        assert tquery(sql_select, con=self.conn) == [
+        assert tquery(sql_select, con=sqlite_buildin) == [
             (1, "A"),
             (2, "B"),
             (3, "C"),
             (4, "D"),
             (5, "E"),
         ]
-        self.drop_table(table_name)
+        self.drop_table(table_name, sqlite_buildin)