implement literal stringification for arrays

as we already implement stringification for the contents,
provide a bracketed syntax for default and ARRAY literal
for PG specifically.   ARRAY literal seems much simpler to
render than their quoted syntax which requires double quotes
for strings.

also open up testing for pg8000 which has likely been
fine with arrays for awhile now, bump the version pin
also.

Fixes: #8138
Change-Id: Id85b052b0a9564d6aa1489160e58b7359f130fdd

1 files changed, 57 insertions, 0 deletions

diff --git a/lib/sqlalchemy/testing/suite/test_types.py b/lib/sqlalchemy/testing/suite/test_types.py
index 391379956..9461298b9 100644
--- a/lib/sqlalchemy/testing/suite/test_types.py
+++ b/lib/sqlalchemy/testing/suite/test_types.py
@@ -17,6 +17,7 @@ from ..config import requirements
 from ..schema import Column
 from ..schema import Table
 from ... import and_
+from ... import ARRAY
 from ... import BigInteger
 from ... import bindparam
 from ... import Boolean
@@ -222,6 +223,61 @@ class UnicodeTextTest(_UnicodeFixture, fixtures.TablesTest):
         self._test_null_strings(connection)
 
 
+class ArrayTest(_LiteralRoundTripFixture, fixtures.TablesTest):
+    """Add ARRAY test suite, #8138.
+
+    This only works on PostgreSQL right now.
+
+    """
+
+    __requires__ = ("array_type",)
+    __backend__ = True
+
+    @classmethod
+    def define_tables(cls, metadata):
+        Table(
+            "array_table",
+            metadata,
+            Column(
+                "id", Integer, primary_key=True, test_needs_autoincrement=True
+            ),
+            Column("single_dim", ARRAY(Integer)),
+            Column("multi_dim", ARRAY(String, dimensions=2)),
+        )
+
+    def test_array_roundtrip(self, connection):
+        array_table = self.tables.array_table
+
+        connection.execute(
+            array_table.insert(),
+            {
+                "id": 1,
+                "single_dim": [1, 2, 3],
+                "multi_dim": [["one", "two"], ["thr'ee", "réve🐍 illé"]],
+            },
+        )
+        row = connection.execute(
+            select(array_table.c.single_dim, array_table.c.multi_dim)
+        ).first()
+        eq_(row, ([1, 2, 3], [["one", "two"], ["thr'ee", "réve🐍 illé"]]))
+
+    def test_literal_simple(self, literal_round_trip):
+        literal_round_trip(
+            ARRAY(Integer),
+            ([1, 2, 3],),
+            ([1, 2, 3],),
+            support_whereclause=False,
+        )
+
+    def test_literal_complex(self, literal_round_trip):
+        literal_round_trip(
+            ARRAY(String, dimensions=2),
+            ([["one", "two"], ["thr'ee", "réve🐍 illé"]],),
+            ([["one", "two"], ["thr'ee", "réve🐍 illé"]],),
+            support_whereclause=False,
+        )
+
+
 class BinaryTest(_LiteralRoundTripFixture, fixtures.TablesTest):
     __requires__ = ("binary_literals",)
     __backend__ = True
@@ -1779,6 +1835,7 @@ class NativeUUIDTest(UuidTest):
 
 
 __all__ = (
+    "ArrayTest",
     "BinaryTest",
     "UnicodeVarcharTest",
     "UnicodeTextTest",