def atomic_create_record(self, fields):
"""Create a record and set field contents atomically."""
if not fields:
raise DataError("Cannot create an empty record")
l = len(fields)
tupletype = type(())
if self.locking:
self.start_write()
try:
r = wgdb.create_raw_record(self._db, l)
for i in range(l):
if type(fields[i]) == tupletype:
data = fields[i][0]
extarg = fields[i][1:]
else:
data = fields[i]
extarg = ()
if isinstance(data, Record):
data = data.get__rec()
fargs = (self._db, r, i, data) + extarg
wgdb.set_new_field(*fargs)
finally:
if self.locking:
self.end_write()
return self._new_record(r)
def test_creation(self):
"""Tests record creation and low level
scanning to retrieve records from the database."""
rec = wgdb.create_record(self.d, 3)
self.assertTrue(wgdb.is_record(rec))
l = wgdb.get_record_len(self.d, rec)
self.assertEqual(l, 3)
rec2 = wgdb.create_raw_record(self.d, 678)
self.assertTrue(wgdb.is_record(rec2))
l = wgdb.get_record_len(self.d, rec2)
self.assertEqual(l, 678)
# wgdb module only allows comparing records by contents
# so we need to use recognizable data for this test.
wgdb.set_field(self.d, rec, 0, 99531179)
wgdb.set_field(self.d, rec2, 0, 55498756)
# XXX: the following relies on certain assumptions on memory
# management of WhiteDB. By the API description, the records
# are not necessarily fetched in order of creation, it is just
# useful for the current test case that it happens to be the case.
#
cand = wgdb.get_first_record(self.d)
self.assertEqual(wgdb.get_field(self.d, cand, 0), 99531179)
cand = wgdb.get_next_record(self.d, cand)
self.assertEqual(wgdb.get_field(self.d, cand, 0), 55498756)
# This, however, should always work correctly
wgdb.delete_record(self.d, rec)
cand = wgdb.get_first_record(self.d)
self.assertEqual(wgdb.get_field(self.d, cand, 0), 55498756)