Moves column dump specific code to a module included in AbstractAdapter

Having column related schema dumper code in the AbstractAdapter. The
code remains the same, but by placing it in the AbstractAdapter, we can
then overwrite it with Adapter specific methods that will help with
Adapter specific data types.

The goal of moving this code here is to create a new migration key for
PostgreSQL's array type. Since any datatype can be an array, the goal is
to have ':array => true' as a migration option, turning the datatype
into an array. I've implemented this in postgres_ext, the syntax is
shown here: https://github.com/dockyard/postgres_ext#arrays

Adds array migration support

Adds array_test.rb outlining the test cases for array data type
Adds pg_array_parser to Gemfile for testing
Adds pg_array_parser to postgresql_adapter (unused in this commit)

Adds schema dump support for arrays

Adds postgres array type casting support

Updates changelog, adds note for inet and cidr support, which I forgot to add before

Removing debugger, Adds pg_array_parser to JRuby platform

Removes pg_array_parser requirement, creates ArrayParser module used by
PostgreSQLAdapter

1 files changed, 2 insertions, 29 deletions

diff --git a/activerecord/lib/active_record/schema_dumper.rb b/activerecord/lib/active_record/schema_dumper.rb
index 310b4c1459..36bde44e7c 100644
--- a/activerecord/lib/active_record/schema_dumper.rb
+++ b/activerecord/lib/active_record/schema_dumper.rb
@@ -107,27 +107,11 @@ HEADER
           column_specs = columns.map do |column|
             raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" if @types[column.type].nil?
             next if column.name == pk
-            spec = {}
-            spec[:name]      = column.name.inspect
-
-            # AR has an optimization which handles zero-scale decimals as integers. This
-            # code ensures that the dumper still dumps the column as a decimal.
-            spec[:type]      = if column.type == :integer && /^(numeric|decimal)/ =~ column.sql_type
-                                 'decimal'
-                               else
-                                 column.type.to_s
-                               end
-            spec[:limit]     = column.limit.inspect if column.limit != @types[column.type][:limit] && spec[:type] != 'decimal'
-            spec[:precision] = column.precision.inspect if column.precision
-            spec[:scale]     = column.scale.inspect if column.scale
-            spec[:null]      = 'false' unless column.null
-            spec[:default]   = default_string(column.default) if column.has_default?
-            (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k.to_s}: ")}
-            spec
+            @connection.column_spec(column, @types)
           end.compact
 
           # find all migration keys used in this table
-          keys = [:name, :limit, :precision, :scale, :default, :null]
+          keys = @connection.migration_keys
 
           # figure out the lengths for each column based on above keys
           lengths = keys.map { |key|
@@ -170,17 +154,6 @@ HEADER
         stream
       end
 
-      def default_string(value)
-        case value
-        when BigDecimal
-          value.to_s
-        when Date, DateTime, Time
-          "'#{value.to_s(:db)}'"
-        else
-          value.inspect
-        end
-      end
-
       def indexes(table, stream)
         if (indexes = @connection.indexes(table)).any?
           add_index_statements = indexes.map do |index|