Fixed adaptation of lists of empty lists

...somehow. Postgres doesn't support them and converts them into a
simple empty array. However this is not really our concern: the syntax
we return is valid.

Close #788
This commit is contained in:
Daniele Varrazzo 2018-10-29 23:15:40 +00:00
parent 2f24a2e22d
commit a83696fc50
3 changed files with 22 additions and 4 deletions

1
NEWS
View File

@ -41,6 +41,7 @@ What's new in psycopg 2.7.6
(:ticket:`#746`).
- Fixed building on modern FreeBSD versions with Python 3.7 (:ticket:`#755`).
- Fixed hang trying to :sql:`COPY` via `~cursor.execute()` (:ticket:`#781`).
- Fixed adaptation of arrays of empty arrays (:ticket:`#788`).
- Fixed segfault accessing the `connection.readonly` and
`connection.deferrable` repeatedly (:ticket:`#790`).
- `~psycopg2.extras.execute_values()` accepts `~psycopg2.sql.Composable`

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@ -55,6 +55,8 @@ list_quote(listObject *self)
/* empty arrays are converted to NULLs (still searching for a way to
insert an empty array in postgresql */
if (len == 0) {
/* it cannot be ARRAY[] because it would make empty lists unusable
* in any() without a cast. But we may convert it into ARRAY[] below */
res = Bytes_FromString("'{}'");
goto exit;
}
@ -79,7 +81,19 @@ list_quote(listObject *self)
/* Lists of arrays containing only nulls are also not supported
* by the ARRAY construct so we should do some special casing */
if (!PyList_Check(wrapped) || Bytes_AS_STRING(qs[i])[0] == 'A') {
if (PyList_Check(wrapped)) {
if (Bytes_AS_STRING(qs[i])[0] == 'A') {
all_nulls = 0;
}
else if (0 == strcmp(Bytes_AS_STRING(qs[i]), "'{}'")) {
/* case of issue #788: '{{}}' is not supported but
* array[array[]] is */
all_nulls = 0;
Py_CLEAR(qs[i]);
qs[i] = Bytes_FromString("ARRAY[]");
}
}
else {
all_nulls = 0;
}
}

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@ -167,9 +167,12 @@ class TypesBasicTests(ConnectingTestCase):
curs.execute("select col from array_test where id = 2")
self.assertEqual(curs.fetchone()[0], [])
# issue #788 (test commented out until issue fixed)
# curs.execute("select null = any(%s)", ([[]], ))
# self.assertFalse(curs.fetchone()[0])
@testutils.skip_before_postgres(8, 4)
def testNestedEmptyArray(self):
# issue #788
curs = self.conn.cursor()
curs.execute("select 10 = any(%s::int[])", ([[]], ))
self.assertFalse(curs.fetchone()[0])
def testEmptyArrayNoCast(self):
s = self.execute("SELECT '{}' AS foo")