1 files changed, 292 insertions, 0 deletions
diff --git a/test/sql/test_join_rewriting.py b/test/sql/test_join_rewriting.py
new file mode 100644
index 000000000..5a9bdd1d3
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+++ b/test/sql/test_join_rewriting.py
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+from sqlalchemy import Table, Column, Integer, MetaData, ForeignKey, select
+from sqlalchemy.testing import fixtures, AssertsCompiledSQL
+from sqlalchemy import util
+from sqlalchemy.engine import default
+from sqlalchemy import testing
+
+
+m = MetaData()
+
+a = Table('a', m,
+        Column('id', Integer, primary_key=True)
+    )
+
+b = Table('b', m,
+        Column('id', Integer, primary_key=True),
+        Column('a_id', Integer, ForeignKey('a.id'))
+    )
+
+c = Table('c', m,
+        Column('id', Integer, primary_key=True),
+        Column('b_id', Integer, ForeignKey('b.id'))
+    )
+
+d = Table('d', m,
+        Column('id', Integer, primary_key=True),
+        Column('c_id', Integer, ForeignKey('c.id'))
+    )
+
+e = Table('e', m,
+        Column('id', Integer, primary_key=True)
+    )
+
+class _JoinRewriteTestBase(AssertsCompiledSQL):
+    def _test(self, s, assert_):
+        self.assert_compile(
+            s,
+            assert_
+        )
+
+        compiled = s.compile(dialect=self.__dialect__)
+        for key, col in zip([c.key for c in s.c], s.inner_columns):
+            key = key % compiled.anon_map
+            assert col in compiled.result_map[key][1]
+
+
+    def test_a_bc(self):
+        j1 = b.join(c)
+        j2 = a.join(j1)
+
+        # TODO: if we remove 'b' or 'c', shouldn't we get just
+        # the subset of cols from anon_1 ?
+
+        # TODO: do this test also with individual cols, things change
+        # lots based on how you go with this
+
+        s = select([a, b, c], use_labels=True).\
+            select_from(j2).\
+            where(b.c.id == 2).\
+            where(c.c.id == 3).order_by(a.c.id, b.c.id, c.c.id)
+
+        self._test(s, self._a_bc)
+
+    def test_a__b_dc(self):
+        j1 = c.join(d)
+        j2 = b.join(j1)
+        j3 = a.join(j2)
+
+        s = select([a, b, c, d], use_labels=True).\
+            select_from(j3).\
+            where(b.c.id == 2).\
+            where(c.c.id == 3).\
+            where(d.c.id == 4).\
+                order_by(a.c.id, b.c.id, c.c.id, d.c.id)
+
+        self._test(
+            s,
+            self._a__b_dc
+        )
+
+    def test_a_bc_comma_a1_selbc(self):
+        # test here we're emulating is
+        # test.orm.inheritance.test_polymorphic_rel:PolymorphicJoinsTest.test_multi_join
+        j1 = b.join(c)
+        j2 = b.join(c).select(use_labels=True).alias()
+        j3 = a.join(j1)
+        a_a = a.alias()
+        j4 = a_a.join(j2)
+
+        s = select([a, a_a, b, c, j2], use_labels=True).\
+                select_from(j3).select_from(j4).order_by(j2.c.b_id)
+
+        self._test(
+            s,
+            self._a_bc_comma_a1_selbc
+        )
+
+class JoinRewriteTest(_JoinRewriteTestBase, fixtures.TestBase):
+    """test rendering of each join with right-nested rewritten as
+    aliased SELECT statements.."""
+
+    @util.classproperty
+    def __dialect__(cls):
+        dialect = default.DefaultDialect()
+        dialect.supports_right_nested_joins = False
+        return dialect
+
+    _a__b_dc = (
+            "SELECT a.id AS a_id, anon_1.b_id AS b_id, "
+            "anon_1.b_a_id AS b_a_id, anon_1.c_id AS c_id, "
+            "anon_1.c_b_id AS c_b_id, anon_1.d_id AS d_id, "
+            "anon_1.d_c_id AS d_c_id "
+            "FROM a JOIN (SELECT b.id AS b_id, b.a_id AS b_a_id, "
+            "anon_2.c_id AS c_id, anon_2.c_b_id AS c_b_id, "
+            "anon_2.d_id AS d_id, anon_2.d_c_id AS d_c_id "
+            "FROM b JOIN (SELECT c.id AS c_id, c.b_id AS c_b_id, "
+            "d.id AS d_id, d.c_id AS d_c_id "
+            "FROM c JOIN d ON c.id = d.c_id) AS anon_2 "
+            "ON b.id = anon_2.c_b_id) AS anon_1 ON a.id = anon_1.b_a_id "
+            "WHERE anon_1.b_id = :id_1 AND anon_1.c_id = :id_2 AND "
+            "anon_1.d_id = :id_3 "
+            "ORDER BY a.id, anon_1.b_id, anon_1.c_id, anon_1.d_id"
+            )
+
+    _a_bc = (
+            "SELECT a.id AS a_id, anon_1.b_id AS b_id, "
+            "anon_1.b_a_id AS b_a_id, anon_1.c_id AS c_id, "
+            "anon_1.c_b_id AS c_b_id FROM a JOIN "
+            "(SELECT b.id AS b_id, b.a_id AS b_a_id, "
+                "c.id AS c_id, c.b_id AS c_b_id "
+                "FROM b JOIN c ON b.id = c.b_id) AS anon_1 "
+            "ON a.id = anon_1.b_a_id "
+            "WHERE anon_1.b_id = :id_1 AND anon_1.c_id = :id_2 "
+            "ORDER BY a.id, anon_1.b_id, anon_1.c_id"
+            )
+
+    _a_bc_comma_a1_selbc = (
+            "SELECT a.id AS a_id, a_1.id AS a_1_id, anon_1.b_id AS b_id, "
+            "anon_1.b_a_id AS b_a_id, anon_1.c_id AS c_id, "
+            "anon_1.c_b_id AS c_b_id, anon_2.b_id AS anon_2_b_id, "
+            "anon_2.b_a_id AS anon_2_b_a_id, anon_2.c_id AS anon_2_c_id, "
+            "anon_2.c_b_id AS anon_2_c_b_id FROM a "
+            "JOIN (SELECT b.id AS b_id, b.a_id AS b_a_id, c.id AS c_id, "
+            "c.b_id AS c_b_id FROM b JOIN c ON b.id = c.b_id) AS anon_1 "
+            "ON a.id = anon_1.b_a_id, "
+            "a AS a_1 JOIN "
+                "(SELECT b.id AS b_id, b.a_id AS b_a_id, "
+                "c.id AS c_id, c.b_id AS c_b_id "
+                "FROM b JOIN c ON b.id = c.b_id) AS anon_2 "
+            "ON a_1.id = anon_2.b_a_id ORDER BY anon_2.b_id"
+        )
+
+class JoinPlainTest(_JoinRewriteTestBase, fixtures.TestBase):
+    """test rendering of each join with normal nesting."""
+    @util.classproperty
+    def __dialect__(cls):
+        dialect = default.DefaultDialect()
+        return dialect
+
+    _a__b_dc = (
+            "SELECT a.id AS a_id, b.id AS b_id, "
+            "b.a_id AS b_a_id, c.id AS c_id, "
+            "c.b_id AS c_b_id, d.id AS d_id, "
+            "d.c_id AS d_c_id "
+            "FROM a JOIN (b JOIN (c JOIN d ON c.id = d.c_id) "
+            "ON b.id = c.b_id) ON a.id = b.a_id "
+            "WHERE b.id = :id_1 AND c.id = :id_2 AND "
+            "d.id = :id_3 "
+            "ORDER BY a.id, b.id, c.id, d.id"
+            )
+
+
+    _a_bc = (
+            "SELECT a.id AS a_id, b.id AS b_id, "
+            "b.a_id AS b_a_id, c.id AS c_id, "
+            "c.b_id AS c_b_id FROM a JOIN "
+            "(b JOIN c ON b.id = c.b_id) "
+            "ON a.id = b.a_id "
+            "WHERE b.id = :id_1 AND c.id = :id_2 "
+            "ORDER BY a.id, b.id, c.id"
+            )
+
+    _a_bc_comma_a1_selbc = (
+            "SELECT a.id AS a_id, a_1.id AS a_1_id, b.id AS b_id, "
+            "b.a_id AS b_a_id, c.id AS c_id, "
+            "c.b_id AS c_b_id, anon_1.b_id AS anon_1_b_id, "
+            "anon_1.b_a_id AS anon_1_b_a_id, anon_1.c_id AS anon_1_c_id, "
+            "anon_1.c_b_id AS anon_1_c_b_id FROM a "
+            "JOIN (b JOIN c ON b.id = c.b_id) "
+            "ON a.id = b.a_id, "
+            "a AS a_1 JOIN "
+                "(SELECT b.id AS b_id, b.a_id AS b_a_id, "
+                "c.id AS c_id, c.b_id AS c_b_id "
+                "FROM b JOIN c ON b.id = c.b_id) AS anon_1 "
+            "ON a_1.id = anon_1.b_a_id ORDER BY anon_1.b_id"
+        )
+
+class JoinNoUseLabelsTest(_JoinRewriteTestBase, fixtures.TestBase):
+    @util.classproperty
+    def __dialect__(cls):
+        dialect = default.DefaultDialect()
+        dialect.supports_right_nested_joins = False
+        return dialect
+
+    def _test(self, s, assert_):
+        s.use_labels = False
+        self.assert_compile(
+            s,
+            assert_
+        )
+
+    _a__b_dc = (
+            "SELECT a.id, b.id, "
+            "b.a_id, c.id, "
+            "c.b_id, d.id, "
+            "d.c_id "
+            "FROM a JOIN (b JOIN (c JOIN d ON c.id = d.c_id) "
+            "ON b.id = c.b_id) ON a.id = b.a_id "
+            "WHERE b.id = :id_1 AND c.id = :id_2 AND "
+            "d.id = :id_3 "
+            "ORDER BY a.id, b.id, c.id, d.id"
+            )
+
+    _a_bc = (
+            "SELECT a.id, b.id, "
+            "b.a_id, c.id, "
+            "c.b_id FROM a JOIN "
+            "(b JOIN c ON b.id = c.b_id) "
+            "ON a.id = b.a_id "
+            "WHERE b.id = :id_1 AND c.id = :id_2 "
+            "ORDER BY a.id, b.id, c.id"
+            )
+
+    _a_bc_comma_a1_selbc = (
+            "SELECT a.id, a_1.id, b.id, "
+            "b.a_id, c.id, "
+            "c.b_id, anon_1.b_id, "
+            "anon_1.b_a_id, anon_1.c_id, "
+            "anon_1.c_b_id FROM a "
+            "JOIN (b JOIN c ON b.id = c.b_id) "
+            "ON a.id = b.a_id, "
+            "a AS a_1 JOIN "
+                "(SELECT b.id AS b_id, b.a_id AS b_a_id, "
+                "c.id AS c_id, c.b_id AS c_b_id "
+                "FROM b JOIN c ON b.id = c.b_id) AS anon_1 "
+            "ON a_1.id = anon_1.b_a_id ORDER BY anon_1.b_id"
+        )
+
+class JoinExecTest(_JoinRewriteTestBase, fixtures.TestBase):
+    """invoke the SQL on the current backend to ensure compatibility"""
+
+    _a_bc = _a_bc_comma_a1_selbc = _a__b_dc = None
+
+    @classmethod
+    def setup_class(cls):
+        m.create_all(testing.db)
+
+    @classmethod
+    def teardown_class(cls):
+        m.drop_all(testing.db)
+
+    def _test(self, selectable, assert_):
+        testing.db.execute(selectable)
+
+
+class DialectFlagTest(fixtures.TestBase, AssertsCompiledSQL):
+    def test_dialect_flag(self):
+        d1 = default.DefaultDialect(supports_right_nested_joins=True)
+        d2 = default.DefaultDialect(supports_right_nested_joins=False)
+
+        j1 = b.join(c)
+        j2 = a.join(j1)
+
+        s = select([a, b, c], use_labels=True).\
+            select_from(j2)
+
+        self.assert_compile(
+            s,
+            "SELECT a.id AS a_id, b.id AS b_id, b.a_id AS b_a_id, c.id AS c_id, "
+            "c.b_id AS c_b_id FROM a JOIN (b JOIN c ON b.id = c.b_id) "
+            "ON a.id = b.a_id",
+            dialect=d1
+        )
+        self.assert_compile(
+            s,
+            "SELECT a.id AS a_id, anon_1.b_id AS b_id, "
+            "anon_1.b_a_id AS b_a_id, "
+            "anon_1.c_id AS c_id, anon_1.c_b_id AS c_b_id "
+            "FROM a JOIN (SELECT b.id AS b_id, b.a_id AS b_a_id, c.id AS c_id, "
+            "c.b_id AS c_b_id FROM b JOIN c ON b.id = c.b_id) AS anon_1 "
+            "ON a.id = anon_1.b_a_id",
+            dialect=d2
+        )