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venv/Lib/site-packages/sqlalchemy/testing/schema.py

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+# testing/schema.py
+# Copyright (C) 2005-2019 the SQLAlchemy authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+from . import config
+from . import exclusions
+from .. import event
+from .. import schema
+
+
+__all__ = ["Table", "Column"]
+
+table_options = {}
+
+
+def Table(*args, **kw):
+    """A schema.Table wrapper/hook for dialect-specific tweaks."""
+
+    test_opts = {k: kw.pop(k) for k in list(kw) if k.startswith("test_")}
+
+    kw.update(table_options)
+
+    if exclusions.against(config._current, "mysql"):
+        if (
+            "mysql_engine" not in kw
+            and "mysql_type" not in kw
+            and "autoload_with" 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 selecting self-refs too.
+    if exclusions.against(config._current, "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 = {k: kw.pop(k) for k in list(kw) if k.startswith("test_")}
+
+    if not config.requirements.foreign_key_ddl.enabled_for_config(config):
+        args = [arg for arg in args if not isinstance(arg, schema.ForeignKey)]
+
+    col = schema.Column(*args, **kw)
+    if test_opts.get("test_needs_autoincrement", False) and kw.get(
+        "primary_key", False
+    ):
+
+        if col.default is None and col.server_default is None:
+            col.autoincrement = True
+
+        # allow any test suite to pick up on this
+        col.info["test_needs_autoincrement"] = True
+
+        # hardcoded rule for firebird, oracle; this should
+        # be moved out
+        if exclusions.against(config._current, "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