test_compiler.py

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import pytest
from sqlalchemy import Column
from sqlalchemy import ForeignKey
from sqlalchemy import func
from sqlalchemy import insert
from sqlalchemy import Integer
from sqlalchemy import MetaData
from sqlalchemy import select
from sqlalchemy import String
from sqlalchemy import Table
from sqlalchemy.schema import CreateTable
from sqlalchemy.sql import column
from sqlalchemy.sql import table

from tests.unit.conftest import sqlalchemy_version
from trino.sqlalchemy.dialect import TrinoDialect

metadata = MetaData()
table_without_catalog = Table(
    'table',
    metadata,
    Column('id', Integer),
    Column('name', String),
)
table_with_catalog = Table(
    'table',
    metadata,
    Column('id', Integer),
    schema='default',
    trino_catalog='other'
)

table_with_pk = Table(
    'table_with_pk',
    metadata,
    Column('id', String, primary_key=True)
)

table_with_fk = Table(
    'table_with_fk',
    metadata,
    Column('id', String, primary_key=True),
    Column('fk', String, ForeignKey('table_with_pk.id'))
)

table_with_unique = Table(
    'table_with_constraint',
    metadata,
    Column('id', String, primary_key=True),
    Column('uniq', String, unique=True)
)


@pytest.fixture
def dialect():
    return TrinoDialect()


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
def test_limit_offset(dialect):
    statement = select(table_without_catalog).limit(10).offset(0)
    query = statement.compile(dialect=dialect)
    assert str(query) == 'SELECT "table".id, "table".name \nFROM "table"\nOFFSET :param_1\nLIMIT :param_2'


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
def test_limit(dialect):
    statement = select(table_without_catalog).limit(10)
    query = statement.compile(dialect=dialect)
    assert str(query) == 'SELECT "table".id, "table".name \nFROM "table"\nLIMIT :param_1'


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
def test_offset(dialect):
    statement = select(table_without_catalog).offset(0)
    query = statement.compile(dialect=dialect)
    assert str(query) == 'SELECT "table".id, "table".name \nFROM "table"\nOFFSET :param_1'


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
def test_cte_insert_order(dialect):
    cte = select(table_without_catalog).cte('cte')
    statement = insert(table_without_catalog).from_select(table_without_catalog.columns, cte)
    query = statement.compile(dialect=dialect)
    assert str(query) == \
        'INSERT INTO "table" (id, name) WITH cte AS \n'\
        '(SELECT "table".id AS id, "table".name AS name \n'\
        'FROM "table")\n'\
        ' SELECT cte.id, cte.name \n'\
        'FROM cte'


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
def test_catalogs_argument(dialect):
    statement = select(table_with_catalog)
    query = statement.compile(dialect=dialect)
    assert str(query) == 'SELECT default."table".id \nFROM "other".default."table"'


def test_catalogs_create_table(dialect):
    statement = CreateTable(table_with_catalog)
    query = statement.compile(dialect=dialect)
    assert str(query) == \
        '\n'\
        'CREATE TABLE "other".default."table" (\n'\
        '\tid INTEGER\n'\
        ')\n'\
        '\n'


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
def test_table_clause(dialect):
    statement = select(table("user", column("id"), column("name"), column("description")))
    query = statement.compile(dialect=dialect)
    assert str(query) == 'SELECT user.id, user.name, user.description \nFROM user'


@pytest.mark.skipif(
    sqlalchemy_version() < "1.4",
    reason="columns argument to select() must be a Python list or other iterable"
)
@pytest.mark.parametrize(
    'function,element',
    [
        ('first_value', func.first_value),
        ('last_value', func.last_value),
        ('nth_value', func.nth_value),
        ('lead', func.lead),
        ('lag', func.lag),
    ]
)
def test_ignore_nulls(dialect, function, element):
    statement = select(
        element(
            table_without_catalog.c.id,
            ignore_nulls=True,
        ).over(partition_by=table_without_catalog.c.name).label('window')
    )
    query = statement.compile(dialect=dialect)
    assert str(query) == \
           f'SELECT {function}("table".id) IGNORE NULLS OVER (PARTITION BY "table".name) AS window '\
           f'\nFROM "table"'

    statement = select(
        element(
            table_without_catalog.c.id,
            ignore_nulls=False,
        ).over(partition_by=table_without_catalog.c.name).label('window')
    )
    query = statement.compile(dialect=dialect)
    assert str(query) == \
           f'SELECT {function}("table".id) OVER (PARTITION BY "table".name) AS window ' \
           f'\nFROM "table"'


@pytest.mark.skipif(
    sqlalchemy_version() < "2.0",
    reason="ImportError: cannot import name 'try_cast' from 'sqlalchemy'"
)
def test_try_cast(dialect):
    from sqlalchemy import try_cast
    statement = select(try_cast(table_without_catalog.c.id, String))
    query = statement.compile(dialect=dialect)
    assert str(query) == 'SELECT try_cast("table".id as VARCHAR) AS id \nFROM "table"'


def test_catalogs_create_table_with_pk(dialect):
    statement = CreateTable(table_with_pk)
    query = statement.compile(dialect=dialect)
    assert 'primary key' not in str(query).lower()


def test_catalogs_create_table_with_fk(dialect):
    statement = CreateTable(table_with_fk)
    query = statement.compile(dialect=dialect)
    assert 'foreign key' not in str(query).lower()


def test_catalogs_create_table_with_unique(dialect):
    statement = CreateTable(table_with_unique)
    query = statement.compile(dialect=dialect)
    assert 'unique' not in str(query).lower()