Added nil case handling to allow rollback migration in case of

invalid column type
    /activerecord/lib/active_record/connection_adapters
    /abstract/schema_definitions.rb:306
    type = type.to_sym

Changed to the following to handle nil case:
    type = type.to_sym if type

Added regression test for this case:
  /activerecord/test/cases/migration_test.rb:554
  if current_adapter?(:SQLite3Adapter)
    def test_allows_sqlite3_rollback_on_invalid_column_type
      Person.connection.create_table :something, force: true do |t|
        t.column :number, :integer
        t.column :name, :string
        t.column :foo, :bar
      end
      assert Person.connection.column_exists?(:something, :foo)
      assert_nothing_raised { Person.connection.remove_column :something, :foo, :bar }
      assert !Person.connection.column_exists?(:something, :foo)
      assert Person.connection.column_exists?(:something, :name)
      assert Person.connection.column_exists?(:something, :number)
    ensure
      Person.connection.drop_table :something, if_exists: true
    end
  end

1 files changed, 17 insertions, 0 deletions

diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index 76a4592ac5..151f3c8efd 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -551,6 +551,23 @@ class MigrationTest < ActiveRecord::TestCase
     end
   end
 
+  if current_adapter?(:SQLite3Adapter)
+    def test_allows_sqlite3_rollback_on_invalid_column_type
+      Person.connection.create_table :something, force: true do |t|
+        t.column :number, :integer
+        t.column :name, :string
+        t.column :foo, :bar
+      end
+      assert Person.connection.column_exists?(:something, :foo)
+      assert_nothing_raised { Person.connection.remove_column :something, :foo, :bar }
+      assert !Person.connection.column_exists?(:something, :foo)
+      assert Person.connection.column_exists?(:something, :name)
+      assert Person.connection.column_exists?(:something, :number)
+    ensure
+      Person.connection.drop_table :something, if_exists: true
+    end
+  end
+
   if current_adapter? :OracleAdapter
     def test_create_table_with_custom_sequence_name
       # table name is 29 chars, the standard sequence name will