Fix `add_index` to normalize column names and options

Currently does not work the following code.

```ruby
  add_index(:people, ["last_name", "first_name"], order: { last_name: :desc, first_name: :asc })
```

Normalize column names and options to fix the issue.

2 files changed, 7 insertions, 0 deletions

diff --git a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
index a70eb5a094..2a528b2cb1 100644
--- a/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/active_schema_test.rb
@@ -28,12 +28,15 @@ class Mysql2ActiveSchemaTest < ActiveRecord::Mysql2TestCase
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name`  ON `people` (`last_name`(15), `first_name`(15)) "
     assert_equal expected, add_index(:people, [:last_name, :first_name], length: 15)
+    assert_equal expected, add_index(:people, ["last_name", "first_name"], length: 15)
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name`  ON `people` (`last_name`(15), `first_name`) "
     assert_equal expected, add_index(:people, [:last_name, :first_name], length: { last_name: 15 })
+    assert_equal expected, add_index(:people, ["last_name", "first_name"], length: { last_name: 15 })
 
     expected = "CREATE  INDEX `index_people_on_last_name_and_first_name`  ON `people` (`last_name`(15), `first_name`(10)) "
     assert_equal expected, add_index(:people, [:last_name, :first_name], length: { last_name: 15, first_name: 10 })
+    assert_equal expected, add_index(:people, ["last_name", :first_name], length: { last_name: 15, "first_name" => 10 })
 
     %w(SPATIAL FULLTEXT UNIQUE).each do |type|
       expected = "CREATE #{type} INDEX `index_people_on_last_name`  ON `people` (`last_name`) "
diff --git a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
index d3c65f3d94..b787de8453 100644
--- a/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/active_schema_test.rb
@@ -39,6 +39,10 @@ class PostgresqlActiveSchemaTest < ActiveRecord::PostgreSQLTestCase
     expected = %(CREATE  INDEX CONCURRENTLY "index_people_on_last_name" ON "people"  ("last_name"))
     assert_equal expected, add_index(:people, :last_name, algorithm: :concurrently)
 
+    expected = %(CREATE  INDEX  "index_people_on_last_name_and_first_name" ON "people"  ("last_name" DESC, "first_name" ASC))
+    assert_equal expected, add_index(:people, [:last_name, :first_name], order: { last_name: :desc, first_name: :asc })
+    assert_equal expected, add_index(:people, ["last_name", :first_name], order: { last_name: :desc, "first_name" => :asc })
+
     %w(gin gist hash btree).each do |type|
       expected = %(CREATE  INDEX  "index_people_on_last_name" ON "people" USING #{type} ("last_name"))
       assert_equal expected, add_index(:people, :last_name, using: type)