1 files changed, 85 insertions, 0 deletions
diff --git a/lib/sqlalchemy/testing/schema.py b/lib/sqlalchemy/testing/schema.py
new file mode 100644
index 000000000..03da78c64
--- /dev/null
+++ b/lib/sqlalchemy/testing/schema.py
@@ -0,0 +1,85 @@
+"""Enhanced versions of schema.Table and schema.Column which establish
+desired state for different backends.
+"""
+
+from . import exclusions
+from sqlalchemy import schema, event
+from . import config
+
+__all__ = 'Table', 'Column',
+
+table_options = {}
+
+def Table(*args, **kw):
+    """A schema.Table wrapper/hook for dialect-specific tweaks."""
+
+    test_opts = dict([(k, kw.pop(k)) for k in kw.keys()
+                      if k.startswith('test_')])
+
+    kw.update(table_options)
+
+    if exclusions.against('mysql'):
+        if 'mysql_engine' not in kw and 'mysql_type' not in kw:
+            if 'test_needs_fk' in test_opts or 'test_needs_acid' in test_opts:
+                kw['mysql_engine'] = 'InnoDB'
+            else:
+                kw['mysql_engine'] = 'MyISAM'
+
+    # Apply some default cascading rules for self-referential foreign keys.
+    # MySQL InnoDB has some issues around seleting self-refs too.
+    if exclusions.against('firebird'):
+        table_name = args[0]
+        unpack = (config.db.dialect.
+                  identifier_preparer.unformat_identifiers)
+
+        # Only going after ForeignKeys in Columns.  May need to
+        # expand to ForeignKeyConstraint too.
+        fks = [fk
+               for col in args if isinstance(col, schema.Column)
+               for fk in col.foreign_keys]
+
+        for fk in fks:
+            # root around in raw spec
+            ref = fk._colspec
+            if isinstance(ref, schema.Column):
+                name = ref.table.name
+            else:
+                # take just the table name: on FB there cannot be
+                # a schema, so the first element is always the
+                # table name, possibly followed by the field name
+                name = unpack(ref)[0]
+            if name == table_name:
+                if fk.ondelete is None:
+                    fk.ondelete = 'CASCADE'
+                if fk.onupdate is None:
+                    fk.onupdate = 'CASCADE'
+
+    return schema.Table(*args, **kw)
+
+
+def Column(*args, **kw):
+    """A schema.Column wrapper/hook for dialect-specific tweaks."""
+
+    test_opts = dict([(k, kw.pop(k)) for k in kw.keys()
+                      if k.startswith('test_')])
+
+    col = schema.Column(*args, **kw)
+    if 'test_needs_autoincrement' in test_opts and \
+        kw.get('primary_key', False) and \
+        exclusions.against('firebird', 'oracle'):
+        def add_seq(c, tbl):
+            c._init_items(
+                schema.Sequence(_truncate_name(
+                        config.db.dialect, tbl.name + '_' + c.name + '_seq'),
+                    optional=True)
+            )
+        event.listen(col, 'after_parent_attach', add_seq, propagate=True)
+    return col
+
+def _truncate_name(dialect, name):
+    if len(name) > dialect.max_identifier_length:
+        return name[0:max(dialect.max_identifier_length - 6, 0)] + \
+                "_" + hex(hash(name) % 64)[2:]
+    else:
+        return name
+