Revert "'with' starts a transaction even on autocommit connections"

This reverts commit e5ad0ab.

NEWS

@@ -92,8 +92,6 @@ What's new in psycopg 2.9.1
 What's new in psycopg 2.9
 -------------------------
 
-- ``with connection`` starts a transaction on autocommit transactions too
-  (:ticket:`#941`).
 - Timezones with fractional minutes are supported on Python 3.7 and following
   (:ticket:`#1272`).
 - Escape table and column names in `~cursor.copy_from()` and

doc/src/usage.rst

@@ -842,9 +842,6 @@ and each ``with`` block is effectively wrapped in a separate transaction::
         finally:
             conn.close()
 
-.. versionchanged:: 2.9
-    ``with connection`` starts a transaction also on autocommit connections.
-
 
 .. index::
     pair: Server side; Cursor

psycopg/connection.h

@@ -145,9 +145,6 @@ struct connectionObject {
 
     /* the pid this connection was created into */
     pid_t procpid;
-
-    /* inside a with block */
-    int entered;
 };
 
 /* map isolation level values into a numeric const */

psycopg/connection_type.c

@@ -407,22 +407,10 @@ psyco_conn_tpc_recover(connectionObject *self, PyObject *dummy)
 static PyObject *
 psyco_conn_enter(connectionObject *self, PyObject *dummy)
 {
-    PyObject *rv = NULL;
-
     EXC_IF_CONN_CLOSED(self);
 
-    if (self->entered) {
-        PyErr_SetString(ProgrammingError,
-            "the connection cannot be re-entered recursively");
-        goto exit;
-    }
-
-    self->entered = 1;
     Py_INCREF(self);
-    rv = (PyObject *)self;
-
-exit:
-    return rv;
+    return (PyObject *)self;
 }
 
 
@@ -440,9 +428,6 @@ psyco_conn_exit(connectionObject *self, PyObject *args)
         goto exit;
     }
 
-    /* even if there will be an error, consider ourselves out */
-    self->entered = 0;
-
     if (type == Py_None) {
         if (!(tmp = PyObject_CallMethod((PyObject *)self, "commit", NULL))) {
             goto exit;

psycopg/pqpath.c

@@ -348,19 +348,14 @@ pq_begin_locked(connectionObject *conn, PyThreadState **tstate)
     char buf[256];  /* buf size must be same as bufsize */
     int result;
 
-    Dprintf("pq_begin_locked: pgconn = %p, %d, status = %d",
+    Dprintf("pq_begin_locked: pgconn = %p, autocommit = %d, status = %d",
             conn->pgconn, conn->autocommit, conn->status);
 
-    if (conn->status != CONN_STATUS_READY) {
+    if (conn->autocommit || conn->status != CONN_STATUS_READY) {
         Dprintf("pq_begin_locked: transaction in progress");
         return 0;
     }
 
-    if (conn->autocommit && !conn->entered) {
-        Dprintf("pq_begin_locked: autocommit and no with block");
-        return 0;
-    }
-
     if (conn->isolevel == ISOLATION_LEVEL_DEFAULT
             && conn->readonly == STATE_DEFAULT
             && conn->deferrable == STATE_DEFAULT) {
@@ -399,10 +394,10 @@ pq_commit(connectionObject *conn)
     Py_BEGIN_ALLOW_THREADS;
     pthread_mutex_lock(&conn->lock);
 
-    Dprintf("pq_commit: pgconn = %p, status = %d",
-            conn->pgconn, conn->status);
+    Dprintf("pq_commit: pgconn = %p, autocommit = %d, status = %d",
+            conn->pgconn, conn->autocommit, conn->status);
 
-    if (conn->status != CONN_STATUS_BEGIN) {
+    if (conn->autocommit || conn->status != CONN_STATUS_BEGIN) {
         Dprintf("pq_commit: no transaction to commit");
         retvalue = 0;
     }
@@ -434,10 +429,10 @@ pq_abort_locked(connectionObject *conn, PyThreadState **tstate)
 {
     int retvalue = -1;
 
-    Dprintf("pq_abort_locked: pgconn = %p, status = %d",
-            conn->pgconn, conn->status);
+    Dprintf("pq_abort_locked: pgconn = %p, autocommit = %d, status = %d",
+            conn->pgconn, conn->autocommit, conn->status);
 
-    if (conn->status != CONN_STATUS_BEGIN) {
+    if (conn->autocommit || conn->status != CONN_STATUS_BEGIN) {
         Dprintf("pq_abort_locked: no transaction to abort");
         return 0;
     }
@@ -496,12 +491,12 @@ pq_reset_locked(connectionObject *conn, PyThreadState **tstate)
 {
     int retvalue = -1;
 
-    Dprintf("pq_reset_locked: pgconn = %p, status = %d",
-            conn->pgconn, conn->status);
+    Dprintf("pq_reset_locked: pgconn = %p, autocommit = %d, status = %d",
+            conn->pgconn, conn->autocommit, conn->status);
 
     conn->mark += 1;
 
-    if (conn->status == CONN_STATUS_BEGIN) {
+    if (!conn->autocommit && conn->status == CONN_STATUS_BEGIN) {
         retvalue = pq_execute_command_locked(conn, "ABORT", tstate);
         if (retvalue != 0) return retvalue;
     }

tests/test_with.py

@@ -155,93 +155,6 @@ def rollback(self):
         curs.execute("select * from test_with")
         self.assertEqual(curs.fetchall(), [])
 
-    def test_cant_reenter(self):
-        raised_ok = False
-        with self.conn:
-            try:
-                with self.conn:
-                    pass
-            except psycopg2.ProgrammingError:
-                raised_ok = True
-
-        self.assert_(raised_ok)
-
-        # Still good
-        with self.conn:
-            pass
-
-    def test_with_autocommit(self):
-        self.conn.autocommit = True
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-        with self.conn:
-            curs = self.conn.cursor()
-            curs.execute("insert into test_with values (1)")
-            self.assertEqual(
-                self.conn.info.transaction_status,
-                ext.TRANSACTION_STATUS_INTRANS,
-            )
-
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-        curs.execute("select count(*) from test_with")
-        self.assertEqual(curs.fetchone()[0], 1)
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-
-    def test_with_autocommit_pyerror(self):
-        self.conn.autocommit = True
-        raised_ok = False
-        try:
-            with self.conn:
-                curs = self.conn.cursor()
-                curs.execute("insert into test_with values (2)")
-                self.assertEqual(
-                    self.conn.info.transaction_status,
-                    ext.TRANSACTION_STATUS_INTRANS,
-                )
-                1 / 0
-        except ZeroDivisionError:
-            raised_ok = True
-
-        self.assert_(raised_ok)
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-        curs.execute("select count(*) from test_with")
-        self.assertEqual(curs.fetchone()[0], 0)
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-
-    def test_with_autocommit_pgerror(self):
-        self.conn.autocommit = True
-        raised_ok = False
-        try:
-            with self.conn:
-                curs = self.conn.cursor()
-                curs.execute("insert into test_with values (2)")
-                self.assertEqual(
-                    self.conn.info.transaction_status,
-                    ext.TRANSACTION_STATUS_INTRANS,
-                )
-                curs.execute("insert into test_with values ('x')")
-        except psycopg2.errors.InvalidTextRepresentation:
-            raised_ok = True
-
-        self.assert_(raised_ok)
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-        curs.execute("select count(*) from test_with")
-        self.assertEqual(curs.fetchone()[0], 0)
-        self.assertEqual(
-            self.conn.info.transaction_status, ext.TRANSACTION_STATUS_IDLE
-        )
-
 
 class WithCursorTestCase(WithTestCase):
     def test_with_ok(self):