Fixed MySQL DOUBLE column type rendering (#371)

* Fixed MySQL DOUBLE column type rendering

Fixes #335.

* A cleaner approach to type adaptation variations

* Removed PostgreSQL float hacks

---------

Co-authored-by: sheinbergon <[email protected]>

Author: agronholm

CHANGES.rst

@@ -11,6 +11,7 @@ Version history
 - Fixed ``AttributeError`` when metadata contains user defined column types
 - Fixed ``AssertionError`` when metadata contains a column type that is a type decorator
   with an all-uppercase name
+- Fixed MySQL ``DOUBLE`` column types being rendered with the wrong arguments
 
 **3.0.0rc5**
 

src/sqlacodegen/generators.py

@@ -26,7 +26,6 @@
     Constraint,
     DefaultClause,
     Enum,
-    Float,
     ForeignKey,
     ForeignKeyConstraint,
     Identity,
@@ -712,14 +711,7 @@ def get_adapted_type(self, coltype: Any) -> Any:
                     # If the adapted column type does not render the same as the
                     # original, don't substitute it
                     if new_coltype.compile(self.bind.engine.dialect) != compiled_type:
-                        # Make an exception to the rule for Float and arrays of Float,
-                        # since at least on PostgreSQL, Float can accurately represent
-                        # both REAL and DOUBLE_PRECISION
-                        if not isinstance(new_coltype, Float) and not (
-                            isinstance(new_coltype, ARRAY)
-                            and isinstance(new_coltype.item_type, Float)
-                        ):
-                            break
+                        break
                 except CompileError:
                     # If the adapted column type can't be compiled, don't substitute it
                     break

tests/test_generator_tables.py

@@ -238,14 +238,15 @@ def test_mysql_column_types(generator: CodeGenerator) -> None:
         generator.metadata,
         Column("id", mysql.INTEGER),
         Column("name", mysql.VARCHAR(255)),
+        Column("double", mysql.DOUBLE(1, 2)),
         Column("set", mysql.SET("one", "two")),
     )
 
     validate_code(
         generator.generate(),
         """\
         from sqlalchemy import Column, Integer, MetaData, String, Table
-        from sqlalchemy.dialects.mysql import SET
+        from sqlalchemy.dialects.mysql import DOUBLE, SET
 
         metadata = MetaData()
 
@@ -254,6 +255,7 @@ def test_mysql_column_types(generator: CodeGenerator) -> None:
             'simple_items', metadata,
             Column('id', Integer),
             Column('name', String(255)),
+            Column('double', DOUBLE(1, 2)),
             Column('set', SET('one', 'two'))
         )
         """,