Prohibit passing non-string instances as text arguments to queries.

Author: elprans

asyncpg/protocol/codecs/text.pyx

@@ -9,7 +9,7 @@ cdef inline as_pg_string_and_size(
         ConnectionSettings settings, obj, char **cstr, ssize_t *size):
 
     if not cpython.PyUnicode_Check(obj):
-        obj = str(obj)
+        raise TypeError('expected str, got {}'.format(type(obj).__name__))
 
     if settings.is_encoding_utf8():
         cstr[0] = PyUnicode_AsUTF8AndSize(obj, size)

tests/test_codecs.py

@@ -487,6 +487,12 @@ async def test_invalid_input(self):
             ('int8', TypeError, 'an integer is required', [
                 '2',
                 'aa',
+            ]),
+            ('text', TypeError, 'expected str, got bytes', [
+                b'foo'
+            ]),
+            ('text', TypeError, 'expected str, got list', [
+                [1]
             ])
         ]
 
@@ -735,7 +741,7 @@ async def test_extra_codec_alias(self):
 
             res = await self.con.fetchval('''
                 SELECT $1::hstore AS result
-            ''', (('foo', 2), ('bar', 3)))
+            ''', (('foo', '2'), ('bar', '3')))
 
             self.assertEqual(res, {'foo': '2', 'bar': '3'})