Support Nested Map Type (#314) (#315)

* Support Nested Map Type (#314)

* Add tests for Map and nested map (#314)

* fix flake8 (#314)

---------

Co-authored-by: aaksenov <aaksenov@dpkapp.ru>

Author: aksenof

clickhouse_sqlalchemy/drivers/base.py

@@ -273,7 +273,7 @@ def _get_column_type(self, name, spec):
             coltype = self.ischema_names['_map']
             inner_types = [
                 self._get_column_type(name, t.strip())
-                for t in inner.split(',')
+                for t in inner.split(',', 1)
             ]
             return coltype(*inner_types)
 

tests/sql/test_selectable.py

@@ -1,4 +1,4 @@
-from sqlalchemy import Column, and_
+from sqlalchemy import Column, and_, func
 from sqlalchemy.exc import CompileError
 from sqlalchemy.sql import expression
 
@@ -585,3 +585,49 @@ def test_distinct_on(self):
             self.compile(query),
             'SELECT DISTINCT ON (t1.x) t1.x FROM t1'
         )
+
+    def test_map_type(self):
+        table = self._make_table(
+            't1',
+            Column('x', types.Int32, primary_key=True),
+            Column('y', types.Map(types.String, types.String))
+        )
+
+        query = select(
+            func.mapKeys(table.c.y), func.mapValues(table.c.y)
+        ).where(
+            func.has(table.c.y, 'foo')
+        )
+        self.assertEqual(
+            self.compile(query, literal_binds=True),
+            'SELECT mapKeys(t1.y) AS "mapKeys_1", '
+            'mapValues(t1.y) AS "mapValues_1" '
+            'FROM t1 '
+            'WHERE has(t1.y, \'foo\')'
+        )
+
+    def test_nested_map_type(self):
+        table = self._make_table(
+            't1',
+            Column('x', types.Int32, primary_key=True),
+            Column(
+                'y',
+                types.Map(
+                    types.String,
+                    types.Map(types.String, types.String)
+                )
+            )
+        )
+
+        query = select(
+            func.mapKeys(table.c.y), func.mapValues(table.c.y)
+        ).where(
+            func.has(table.c.y, 'foo')
+        )
+        self.assertEqual(
+            self.compile(query, literal_binds=True),
+            'SELECT mapKeys(t1.y) AS "mapKeys_1", '
+            'mapValues(t1.y) AS "mapValues_1" '
+            'FROM t1 '
+            'WHERE has(t1.y, \'foo\')'
+        )