1 files changed, 42 insertions, 16 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
index f9e1e046ea..ce50590651 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/schema_statements.rb
@@ -1,15 +1,11 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module ConnectionAdapters
     module MySQL
       module SchemaStatements # :nodoc:
         # Returns an array of indexes for the given table.
-        def indexes(table_name, name = nil)
-          if name
-            ActiveSupport::Deprecation.warn(<<-MSG.squish)
-              Passing name to #indexes is deprecated without replacement.
-            MSG
-          end
-
+        def indexes(table_name)
           indexes = []
           current_index = nil
           execute_and_free("SHOW KEYS FROM #{quote_table_name(table_name)}", "SCHEMA") do |result|
@@ -26,23 +22,33 @@ module ActiveRecord
                   index_using = mysql_index_type
                 end
 
-                indexes << IndexDefinition.new(
+                indexes << [
                   row[:Table],
                   row[:Key_name],
                   row[:Non_unique].to_i == 0,
+                  [],
+                  lengths: {},
+                  orders: {},
                   type: index_type,
                   using: index_using,
                   comment: row[:Index_comment].presence
-                )
+                ]
               end
 
-              indexes.last.columns << row[:Column_name]
-              indexes.last.lengths.merge!(row[:Column_name] => row[:Sub_part].to_i) if row[:Sub_part]
-              indexes.last.orders.merge!(row[:Column_name] => :desc) if row[:Collation] == "D"
+              indexes.last[-2] << row[:Column_name]
+              indexes.last[-1][:lengths].merge!(row[:Column_name] => row[:Sub_part].to_i) if row[:Sub_part]
+              indexes.last[-1][:orders].merge!(row[:Column_name] => :desc) if row[:Collation] == "D"
             end
           end
 
-          indexes
+          indexes.map { |index| IndexDefinition.new(*index) }
+        end
+
+        def remove_column(table_name, column_name, type = nil, options = {})
+          if foreign_key_exists?(table_name, column: column_name)
+            remove_foreign_key(table_name, column: column_name)
+          end
+          super
         end
 
         def internal_string_options_for_primary_key
@@ -53,6 +59,14 @@ module ActiveRecord
           end
         end
 
+        def update_table_definition(table_name, base)
+          MySQL::Table.new(table_name, base)
+        end
+
+        def create_schema_dumper(options)
+          MySQL::SchemaDumper.create(self, options)
+        end
+
         private
           CHARSETS_OF_4BYTES_MAXLEN = ["utf8mb4", "utf16", "utf16le", "utf32"]
 
@@ -66,8 +80,8 @@ module ActiveRecord
 
           def new_column_from_field(table_name, field)
             type_metadata = fetch_type_metadata(field[:Type], field[:Extra])
-            if type_metadata.type == :datetime && field[:Default] == "CURRENT_TIMESTAMP"
-              default, default_function = nil, field[:Default]
+            if type_metadata.type == :datetime && /\ACURRENT_TIMESTAMP(?:\(\))?\z/i.match?(field[:Default])
+              default, default_function = nil, "CURRENT_TIMESTAMP"
             else
               default, default_function = field[:Default], nil
             end
@@ -92,10 +106,22 @@ module ActiveRecord
             super unless specifier == "RESTRICT"
           end
 
+          def add_index_length(quoted_columns, **options)
+            lengths = options_for_index_columns(options[:length])
+            quoted_columns.each do |name, column|
+              column << "(#{lengths[name]})" if lengths[name].present?
+            end
+          end
+
+          def add_options_for_index_columns(quoted_columns, **options)
+            quoted_columns = add_index_length(quoted_columns, options)
+            super
+          end
+
           def data_source_sql(name = nil, type: nil)
             scope = quoted_scope(name, type: type)
 
-            sql = "SELECT table_name FROM information_schema.tables"
+            sql = "SELECT table_name FROM information_schema.tables".dup
             sql << " WHERE table_schema = #{scope[:schema]}"
             sql << " AND table_name = #{scope[:name]}" if scope[:name]
             sql << " AND table_type = #{scope[:type]}" if scope[:type]