implement full copy for indexes in batch

Fixed issue in batch mode where CREATE INDEX would not use a new column
name in the case of a column rename.

Indexes were previously being moved to the new table without any
steps to rewrite columns.   We now vendor the copy approach
from table.to_metadata so that there's a new index expressed
in terms of the new columns.

Change-Id: Ied84232037aee0b2bf2094b3d3474013d7b41b34
Fixes: #1034

1 files changed, 25 insertions, 7 deletions

diff --git a/tests/test_batch.py b/tests/test_batch.py
index f0bbd75..b19fa98 100644
--- a/tests/test_batch.py
+++ b/tests/test_batch.py
@@ -281,16 +281,20 @@ class BatchApplyTest(TestBase):
         create_stmt = re.sub(r"[\n\t]", "", create_stmt)
 
         idx_stmt = ""
-        for idx in impl.indexes.values():
-            idx_stmt += str(CreateIndex(idx).compile(dialect=context.dialect))
-        for idx in impl.new_indexes.values():
-            impl.new_table.name = impl.table.name
+
+        # create indexes; these should be created in terms of the
+        # final table name
+        impl.new_table.name = impl.table.name
+
+        for idx in impl._gather_indexes_from_both_tables():
             idx_stmt += str(CreateIndex(idx).compile(dialect=context.dialect))
-            impl.new_table.name = ApplyBatchImpl._calc_temp_name(
-                impl.table.name
-            )
+
         idx_stmt = re.sub(r"[\n\t]", "", idx_stmt)
 
+        # revert new table name to the temp name, assertions below
+        # are looking for the temp name
+        impl.new_table.name = ApplyBatchImpl._calc_temp_name(impl.table.name)
+
         if ddl_contains:
             assert ddl_contains in create_stmt + idx_stmt
         if ddl_not_contains:
@@ -357,6 +361,20 @@ class BatchApplyTest(TestBase):
         new_table = self._assert_impl(impl)
         eq_(new_table.c.x.name, "q")
 
+    def test_rename_col_w_index(self):
+        impl = self._ix_fixture()
+        impl.alter_column("tname", "y", name="y2")
+        new_table = self._assert_impl(
+            impl, ddl_contains="CREATE INDEX ix1 ON tname (y2)"
+        )
+        eq_(new_table.c.y.name, "y2")
+
+    def test_rename_col_w_uq(self):
+        impl = self._uq_fixture()
+        impl.alter_column("tname", "y", name="y2")
+        new_table = self._assert_impl(impl, ddl_contains="UNIQUE (y2)")
+        eq_(new_table.c.y.name, "y2")
+
     def test_alter_column_comment(self):
         impl = self._simple_fixture()
         impl.alter_column("tname", "x", comment="some comment")