Executor doesn't work when GROUP BY..ORDER BY COUNT(*)

[stonyw]

sqlglot==16.8.1

    def test_execute_group_by_order_by_count(self):
        tables = {
            "x": [
                {"t": "a", "a": 6, "y": 2019},
                {"t": "b", "a": 12, "y": 2019},
                {"t": "c", "a": 15, "y": 2019},
                {"t": "a", "a": 10, "y": 2018},
                {"t": "b", "a": 12, "y": 2018},
                {"t": "c", "a": 2, "y": 2018},
                {"t": "a", "a": 9, "y": 2017},
            ],
        }
        schema = {
            "x": {
                "t": "text",
                "a": "number",
                "y": "number"
            },
        }
        gen = SqlGenerator("mysql")
        creates = gen.get_sql_tables_schema(schema)
        for c in creates:
            print(c.sql(pretty=True, dialect="mysql"), ";", sep="")
        inserts = gen.get_sql_tables_content(tables)
        for i in inserts:
            print(i.sql(pretty=True, dialect="mysql"), ";", sep="")

        for sql, cols, rows in [
            ('select t , sum ( a ) from x group by t order by avg(a)  asc limit 1;', ["t", "_col_1"], [("a", 25)]), # PASS
            ('select t , sum ( a ) from x group by t order by count ( * ) asc limit 1;', ["t", "_col_1"], [("b", 24)]),  # FAIL
        ]:
            with self.subTest(sql):
                result = execute(sql, read="mysql", schema=schema, tables=tables)
                self.assertEqual(result.columns, tuple(cols))
                self.assertEqual(result.rows, rows)

SubTest error: Traceback (most recent call last):
  File "/Users/.../python3.11/site-packages/sqlglot/executor/python.py", line 40, in execute
    contexts[node] = self.aggregate(node, context)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/python.py", line 288, in aggregate
    add_row()
  File "/Users/.../python3.11/site-packages/sqlglot/executor/python.py", line 278, in add_row
    table.append(group + context.eval_tuple(aggregations))
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/context.py", line 38, in eval_tuple
    return tuple(self.eval(code) for code in codes)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/./python3.11/site-packages/sqlglot/executor/context.py", line 38, in <genexpr>
    return tuple(self.eval(code) for code in codes)
                 ^^^^^^^^^^^^^^^
  File "/Users/./python3.11/site-packages/sqlglot/executor/context.py", line 35, in eval
    return eval(code, self.env)
           ^^^^^^^^^^^^^^^^^^^^
  File "COUNT(scope[None]["_a_1"])", line 1, in <module>
KeyError: None


The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/.../python3.11/unittest/case.py", line 57, in testPartExecutor
    yield
  File "/usr/.../python3.11/unittest/case.py", line 538, in subTest
    yield
  File "/Users/.../src/tr/dbtool/test_executor.py", line 237, in test_execute_group_by_order_by_count
    result = execute(sql, read="mysql", schema=schema, tables=tables)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/..../python3.11/site-packages/sqlglot/executor/__init__.py", line 82, in execute
    result = PythonExecutor(tables=tables_).execute(plan)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/.../python3.11/site-packages/sqlglot/executor/python.py", line 60, in execute
    raise ExecuteError(f"Step '{node.id}' failed: {e}") from e
sqlglot.errors.ExecuteError: Step 'Aggregate: x (4552043856)' failed: None

[georgesittas]

I'll take a look, thanks