Default create_constraint to False

The :paramref:`.Enum.create_constraint` and
:paramref:`.Boolean.create_constraint` parameters now default to False,
indicating when a so-called "non-native" version of these two datatypes is
created, a CHECK constraint will not be generated by default.   These CHECK
constraints present schema-management maintenance complexities that should
be opted in to, rather than being turned on by default.

Fixes: #5367
Change-Id: I0a3fb608ce32143fa757546cc17ba2013e93272a

2 files changed, 93 insertions, 21 deletions

diff --git a/test/sql/test_metadata.py b/test/sql/test_metadata.py
index a75aee6e9..2145e72d0 100644
--- a/test/sql/test_metadata.py
+++ b/test/sql/test_metadata.py
@@ -2258,7 +2258,7 @@ class SchemaTypeTest(fixtures.TestBase):
     def test_boolean_constraint_type_doesnt_double(self):
         m1 = MetaData()
 
-        t1 = Table("x", m1, Column("flag", Boolean()))
+        t1 = Table("x", m1, Column("flag", Boolean(create_constraint=True)))
         eq_(
             len([c for c in t1.constraints if isinstance(c, CheckConstraint)]),
             1,
@@ -2274,7 +2274,11 @@ class SchemaTypeTest(fixtures.TestBase):
     def test_enum_constraint_type_doesnt_double(self):
         m1 = MetaData()
 
-        t1 = Table("x", m1, Column("flag", Enum("a", "b", "c")))
+        t1 = Table(
+            "x",
+            m1,
+            Column("flag", Enum("a", "b", "c", create_constraint=True)),
+        )
         eq_(
             len([c for c in t1.constraints if isinstance(c, CheckConstraint)]),
             1,
@@ -5031,7 +5035,11 @@ class NamingConventionTest(fixtures.TestBase, AssertsCompiledSQL):
             naming_convention={"ck": "ck_%(table_name)s_%(constraint_name)s"}
         )
 
-        u1 = Table("user", m1, Column("x", Boolean(name="foo")))
+        u1 = Table(
+            "user",
+            m1,
+            Column("x", Boolean(name="foo", create_constraint=True)),
+        )
         # constraint is not hit
         eq_(
             [c for c in u1.constraints if isinstance(c, CheckConstraint)][
@@ -5053,7 +5061,7 @@ class NamingConventionTest(fixtures.TestBase, AssertsCompiledSQL):
             naming_convention={"ck": "ck_%(table_name)s_%(column_0_name)s"}
         )
 
-        u1 = Table("user", m1, Column("x", Boolean()))
+        u1 = Table("user", m1, Column("x", Boolean(create_constraint=True)))
         # constraint is not hit
         is_(
             [c for c in u1.constraints if isinstance(c, CheckConstraint)][
@@ -5075,7 +5083,11 @@ class NamingConventionTest(fixtures.TestBase, AssertsCompiledSQL):
             naming_convention={"ck": "ck_%(table_name)s_%(constraint_name)s"}
         )
 
-        u1 = Table("user", m1, Column("x", Enum("a", "b", name="foo")))
+        u1 = Table(
+            "user",
+            m1,
+            Column("x", Enum("a", "b", name="foo", create_constraint=True)),
+        )
         eq_(
             [c for c in u1.constraints if isinstance(c, CheckConstraint)][
                 0
@@ -5097,7 +5109,14 @@ class NamingConventionTest(fixtures.TestBase, AssertsCompiledSQL):
         )
 
         u1 = Table(
-            "user", m1, Column("x", Enum("a", "b", name=naming.conv("foo")))
+            "user",
+            m1,
+            Column(
+                "x",
+                Enum(
+                    "a", "b", name=naming.conv("foo"), create_constraint=True
+                ),
+            ),
         )
         eq_(
             [c for c in u1.constraints if isinstance(c, CheckConstraint)][
@@ -5119,7 +5138,7 @@ class NamingConventionTest(fixtures.TestBase, AssertsCompiledSQL):
             naming_convention={"ck": "ck_%(table_name)s_%(constraint_name)s"}
         )
 
-        u1 = Table("user", m1, Column("x", Boolean()))
+        u1 = Table("user", m1, Column("x", Boolean(create_constraint=True)))
         # constraint gets special _defer_none_name
         is_(
             [c for c in u1.constraints if isinstance(c, CheckConstraint)][
@@ -5145,7 +5164,7 @@ class NamingConventionTest(fixtures.TestBase, AssertsCompiledSQL):
     def test_schematype_no_ck_name_boolean_no_name(self):
         m1 = MetaData()  # no naming convention
 
-        u1 = Table("user", m1, Column("x", Boolean()))
+        u1 = Table("user", m1, Column("x", Boolean(create_constraint=True)))
         # constraint gets special _defer_none_name
         is_(
             [c for c in u1.constraints if isinstance(c, CheckConstraint)][
diff --git a/test/sql/test_types.py b/test/sql/test_types.py
index a0c4ee022..30e5d1fca 100644
--- a/test/sql/test_types.py
+++ b/test/sql/test_types.py
@@ -1331,25 +1331,43 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
 
     @classmethod
     def define_tables(cls, metadata):
+        # note create_constraint has changed in 1.4 as of #5367
         Table(
             "enum_table",
             metadata,
             Column("id", Integer, primary_key=True),
-            Column("someenum", Enum("one", "two", "three", name="myenum")),
+            Column(
+                "someenum",
+                Enum(
+                    "one",
+                    "two",
+                    "three",
+                    name="myenum",
+                    create_constraint=True,
+                ),
+            ),
         )
 
         Table(
             "non_native_enum_table",
             metadata,
             Column("id", Integer, primary_key=True, autoincrement=False),
-            Column("someenum", Enum("one", "two", "three", native_enum=False)),
+            Column(
+                "someenum",
+                Enum(
+                    "one",
+                    "two",
+                    "three",
+                    native_enum=False,
+                    create_constraint=True,
+                ),
+            ),
             Column(
                 "someotherenum",
                 Enum(
                     "one",
                     "two",
                     "three",
-                    create_constraint=False,
                     native_enum=False,
                     validate_strings=True,
                 ),
@@ -1360,7 +1378,7 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
             "stdlib_enum_table",
             metadata,
             Column("id", Integer, primary_key=True),
-            Column("someenum", Enum(cls.SomeEnum)),
+            Column("someenum", Enum(cls.SomeEnum, create_constraint=True)),
         )
 
         Table(
@@ -1372,6 +1390,7 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
                 Enum(
                     cls.SomeOtherEnum,
                     values_callable=EnumTest.get_enum_string_values,
+                    create_constraint=True,
                 ),
             ),
         )
@@ -1605,9 +1624,21 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
             Column(
                 "data",
                 Enum(
-                    "one", "two", "three", native_enum=False, name="e1"
+                    "one",
+                    "two",
+                    "three",
+                    native_enum=False,
+                    name="e1",
+                    create_constraint=True,
                 ).with_variant(
-                    Enum("four", "five", "six", native_enum=False, name="e2"),
+                    Enum(
+                        "four",
+                        "five",
+                        "six",
+                        native_enum=False,
+                        name="e2",
+                        create_constraint=True,
+                    ),
                     "some_other_db",
                 ),
             ),
@@ -1638,9 +1669,21 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
             Column(
                 "data",
                 Enum(
-                    "one", "two", "three", native_enum=False, name="e1"
+                    "one",
+                    "two",
+                    "three",
+                    native_enum=False,
+                    name="e1",
+                    create_constraint=True,
                 ).with_variant(
-                    Enum("four", "five", "six", native_enum=False, name="e2"),
+                    Enum(
+                        "four",
+                        "five",
+                        "six",
+                        native_enum=False,
+                        name="e2",
+                        create_constraint=True,
+                    ),
                     testing.db.dialect.name,
                 ),
             ),
@@ -1896,7 +1939,10 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
         class MyEnum(TypeDecorator):
             def __init__(self, values):
                 self.impl = Enum(
-                    *[v.name for v in values], name="myenum", native_enum=False
+                    *[v.name for v in values],
+                    name="myenum",
+                    native_enum=False,
+                    create_constraint=True
                 )
 
             # future method
@@ -1931,7 +1977,11 @@ class EnumTest(AssertsCompiledSQL, fixtures.TablesTest):
         are created with checkfirst=False"""
 
         e = engines.mock_engine()
-        t = Table("t1", MetaData(), Column("x", Enum("x", "y", name="pge")))
+        t = Table(
+            "t1",
+            MetaData(),
+            Column("x", Enum("x", "y", name="pge", create_constraint=True)),
+        )
         t.create(e, checkfirst=False)
         # basically looking for the start of
         # the constraint, or the ENUM def itself,
@@ -3038,6 +3088,9 @@ class BooleanTest(
     """test edge cases for booleans.  Note that the main boolean test suite
     is now in testing/suite/test_types.py
 
+    the default value of create_constraint was changed to False in
+    version 1.4 with #5367.
+
     """
 
     __backend__ = True
@@ -3048,8 +3101,8 @@ class BooleanTest(
             "boolean_table",
             metadata,
             Column("id", Integer, primary_key=True, autoincrement=False),
-            Column("value", Boolean),
-            Column("unconstrained_value", Boolean(create_constraint=False)),
+            Column("value", Boolean(create_constraint=True)),
+            Column("unconstrained_value", Boolean()),
         )
 
     @testing.fails_on(
@@ -3078,7 +3131,7 @@ class BooleanTest(
                 self.value = value
 
         class MyBool(TypeDecorator):
-            impl = Boolean()
+            impl = Boolean(create_constraint=True)
 
             # future method
             def process_literal_param(self, value, dialect):