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

12 files changed, 435 insertions, 53 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 8c99a3929e..475c237009 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -23,6 +23,37 @@
 
     *kennyj*
 
+*   PostgreSQL inet and cidr types are converted to `IPAddr` objects.
+    *Dan McClain*
+
+*   PostgreSQL array type support. Any datatype can be used to create an
+    array column, with full migration and schema dumper support.
+
+    To declare an array column, use the following syntax:
+
+        create_table :table_with_arrays do |t|
+          t.integer :int_array, :array => true
+          # integer[]
+          t.integer :int_array, :array => true, :length => 2
+          # smallint[]
+          t.string :string_array, :array => true, :length => 30
+          # char varying(30)[]
+        end 
+
+    This respects any other migraion detail (limits, defaults, etc).
+    ActiveRecord will serialize and deserialize the array columns on
+    their way to and from the database.
+
+    One thing to note: PostgreSQL does not enforce any limits on the
+    number of elements, and any array can be multi-dimensional. Any
+    array that is multi-dimensional must be rectangular (each sub array
+    must have the same number of elements as its siblings).
+
+    If the `pg_array_parser` gem is available, it will be used when
+    parsing PostgreSQL's array representation
+
+    *Dan McClain*
+
 *   Attribute predicate methods, such as `article.title?`, will now raise
     `ActiveModel::MissingAttributeError` if the attribute being queried for
     truthiness was not read from the database, instead of just returning false.
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
new file mode 100644
index 0000000000..9d6111b51e
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
@@ -0,0 +1,56 @@
+module ActiveRecord
+  module ConnectionAdapters # :nodoc:
+    # The goal of this module is to move Adapter specific column
+    # definitions to the Adapter instead of having it in the schema
+    # dumper itself. This code represents the normal case.
+    # We can then redefine how certain data types may be handled in the schema dumper on the 
+    # Adapter level by over-writing this code inside the database spececific adapters
+    module ColumnDumper
+      def column_spec(column, types)
+        spec = prepare_column_options(column, types)
+        (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k.to_s}: ")}
+        spec
+      end
+
+      # This can be overridden on a Adapter level basis to support other
+      # extended datatypes (Example: Adding an array option in the
+      # PostgreSQLAdapter)
+      def prepare_column_options(column, types)
+        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
+      end
+
+      # Lists the valid migration options
+      def migration_keys
+        [:name, :limit, :precision, :scale, :default, :null]
+      end
+
+      private
+
+        def default_string(value)
+          case value
+          when BigDecimal
+            value.to_s
+          when Date, DateTime, Time
+            "'#{value.to_s(:db)}'"
+          else
+            value.inspect
+          end
+        end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index 27700e4fd2..d5c7caad2e 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -3,6 +3,7 @@ require 'bigdecimal'
 require 'bigdecimal/util'
 require 'active_support/core_ext/benchmark'
 require 'active_record/connection_adapters/schema_cache'
+require 'active_record/connection_adapters/abstract/schema_dumper' 
 require 'monitor'
 
 module ActiveRecord
@@ -52,6 +53,7 @@ module ActiveRecord
       include QueryCache
       include ActiveSupport::Callbacks
       include MonitorMixin
+      include ColumnDumper
 
       define_callbacks :checkout, :checkin
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/array_parser.rb b/activerecord/lib/active_record/connection_adapters/postgresql/array_parser.rb
new file mode 100644
index 0000000000..b7d24f2bb3
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/array_parser.rb
@@ -0,0 +1,97 @@
+module ActiveRecord
+  module ConnectionAdapters
+    class PostgreSQLColumn < Column
+      module ArrayParser
+        private
+          # Loads pg_array_parser if available. String parsing can be
+          # performed quicker by a native extension, which will not create
+          # a large amount of Ruby objects that will need to be garbage
+          # collected. pg_array_parser has a C and Java extension
+          begin
+            require 'pg_array_parser'
+            include PgArrayParser
+          rescue LoadError
+            def parse_pg_array(string)
+              parse_data(string, 0)
+            end
+          end
+
+          def parse_data(string, index)
+            local_index = index
+            array = []
+            while(local_index < string.length)
+              case string[local_index]
+              when '{'
+                local_index,array = parse_array_contents(array, string, local_index + 1)
+              when '}'
+                return array
+              end
+              local_index += 1
+            end
+
+            array
+          end
+
+          def parse_array_contents(array, string, index)
+            is_escaping = false
+            is_quoted = false
+            was_quoted = false
+            current_item = ''
+
+            local_index = index
+            while local_index
+              token = string[local_index]
+              if is_escaping
+                current_item << token
+                is_escaping = false
+              else
+                if is_quoted
+                  case token
+                  when '"'
+                    is_quoted = false
+                    was_quoted = true
+                  when "\\"
+                    is_escaping = true
+                  else
+                    current_item << token
+                  end
+                else
+                  case token
+                  when "\\"
+                    is_escaping = true
+                  when ','
+                    add_item_to_array(array, current_item, was_quoted)
+                    current_item = ''
+                    was_quoted = false
+                  when '"'
+                    is_quoted = true
+                  when '{'
+                    internal_items = []
+                    local_index,internal_items = parse_array_contents(internal_items, string, local_index + 1)
+                    array.push(internal_items)
+                  when '}'
+                    add_item_to_array(array, current_item, was_quoted)
+                    return local_index,array
+                  else
+                    current_item << token
+                  end
+                end
+              end
+
+              local_index += 1
+            end
+            return local_index,array
+          end
+
+          def add_item_to_array(array, current_item, quoted)
+            if current_item.length == 0
+            elsif !quoted && current_item == 'NULL'
+              array.push nil
+            else
+              array.push current_item
+            end
+          end
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/cast.rb b/activerecord/lib/active_record/connection_adapters/postgresql/cast.rb
index b59195f98a..62d091357d 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/cast.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/cast.rb
@@ -45,6 +45,21 @@ module ActiveRecord
           end
         end
 
+        def array_to_string(value, column, adapter, should_be_quoted = false)
+          casted_values = value.map do |val|
+            if String === val
+              if val == "NULL"
+                "\"#{val}\""
+              else
+                quote_and_escape(adapter.type_cast(val, column, true))
+              end
+            else
+              adapter.type_cast(val, column, true)
+            end
+          end
+          "{#{casted_values.join(',')}}"
+        end
+
         def string_to_json(string)
           if String === string
             ActiveSupport::JSON.decode(string)
@@ -71,6 +86,10 @@ module ActiveRecord
           end
         end
 
+        def string_to_array(string, oid)
+          parse_pg_array(string).map{|val| oid.type_cast val}
+        end
+
         private
 
           HstorePair = begin
@@ -90,6 +109,15 @@ module ActiveRecord
               end
             end
           end
+
+          def quote_and_escape(value)
+            case value
+            when "NULL"
+              value
+            else
+              "\"#{value.gsub(/"/,"\\\"")}\""
+            end
+          end
       end
     end
   end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
index b8e7687b21..52344f61c0 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid.rb
@@ -63,6 +63,21 @@ module ActiveRecord
           end
         end
 
+        class Array < Type
+          attr_reader :subtype
+          def initialize(subtype)
+            @subtype = subtype
+          end
+
+          def type_cast(value)
+            if String === value
+              ConnectionAdapters::PostgreSQLColumn.string_to_array value, @subtype
+            else
+              value
+            end
+          end
+        end
+
         class Integer < Type
           def type_cast(value)
             return if value.nil?
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
index 85721601a9..37d43d891d 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
@@ -19,6 +19,12 @@ module ActiveRecord
           return super unless column
 
           case value
+          when Array
+            if column.array
+              "'#{PostgreSQLColumn.array_to_string(value, column, self)}'"
+            else
+              super
+            end
           when Hash
             case column.sql_type
             when 'hstore' then super(PostgreSQLColumn.hstore_to_string(value), column)
@@ -59,24 +65,35 @@ module ActiveRecord
           end
         end
 
-        def type_cast(value, column)
-          return super unless column
+        def type_cast(value, column, array_member = false)
+          return super(value, column) unless column
 
           case value
+          when NilClass
+            if column.array && array_member
+              'NULL'
+            elsif column.array
+              value
+            else
+              super(value, column)
+            end
+          when Array
+            return super(value, column) unless column.array
+            PostgreSQLColumn.array_to_string(value, column, self)
           when String
-            return super unless 'bytea' == column.sql_type
+            return super(value, column) unless 'bytea' == column.sql_type
             { :value => value, :format => 1 }
           when Hash
             case column.sql_type
             when 'hstore' then PostgreSQLColumn.hstore_to_string(value)
             when 'json' then PostgreSQLColumn.json_to_string(value)
-            else super
+            else super(value, column)
             end
           when IPAddr
-            return super unless ['inet','cidr'].includes? column.sql_type
+            return super(value, column) unless ['inet','cidr'].includes? column.sql_type
             PostgreSQLColumn.cidr_to_string(value)
           else
-            super
+            super(value, column)
           end
         end
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index d1751d70c6..1a727f9aa6 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -2,6 +2,7 @@ require 'active_record/connection_adapters/abstract_adapter'
 require 'active_record/connection_adapters/statement_pool'
 require 'active_record/connection_adapters/postgresql/oid'
 require 'active_record/connection_adapters/postgresql/cast'
+require 'active_record/connection_adapters/postgresql/array_parser'
 require 'active_record/connection_adapters/postgresql/quoting'
 require 'active_record/connection_adapters/postgresql/schema_statements'
 require 'active_record/connection_adapters/postgresql/database_statements'
@@ -41,16 +42,23 @@ module ActiveRecord
   module ConnectionAdapters
     # PostgreSQL-specific extensions to column definitions in a table.
     class PostgreSQLColumn < Column #:nodoc:
+      attr_accessor :array
       # Instantiates a new PostgreSQL column definition in a table.
       def initialize(name, default, oid_type, sql_type = nil, null = true)
         @oid_type = oid_type
-        super(name, self.class.extract_value_from_default(default), sql_type, null)
+        if sql_type =~ /\[\]$/
+          @array = true
+          super(name, self.class.extract_value_from_default(default), sql_type[0..sql_type.length - 3], null)
+        else
+          @array = false
+          super(name, self.class.extract_value_from_default(default), sql_type, null)
+        end
       end
 
       # :stopdoc:
       class << self
         include ConnectionAdapters::PostgreSQLColumn::Cast
-
+        include ConnectionAdapters::PostgreSQLColumn::ArrayParser
         attr_accessor :money_precision
       end
       # :startdoc:
@@ -243,6 +251,10 @@ module ActiveRecord
     # In addition, default connection parameters of libpq can be set per environment variables.
     # See http://www.postgresql.org/docs/9.1/static/libpq-envars.html .
     class PostgreSQLAdapter < AbstractAdapter
+      class ColumnDefinition < ActiveRecord::ConnectionAdapters::ColumnDefinition
+        attr_accessor :array
+      end
+
       class TableDefinition < ActiveRecord::ConnectionAdapters::TableDefinition
         def xml(*args)
           options = args.extract_options!
@@ -277,6 +289,23 @@ module ActiveRecord
         def json(name, options = {})
           column(name, 'json', options)
         end
+
+        def column(name, type = nil, options = {})
+          super
+          column = self[name]
+          column.array = options[:array]
+
+          self
+        end
+
+        private
+
+        def new_column_definition(base, name, type)
+          definition = ColumnDefinition.new base, name, type
+          @columns << definition
+          @columns_hash[name] = definition
+          definition
+        end
       end
 
       ADAPTER_NAME = 'PostgreSQL'
@@ -314,6 +343,19 @@ module ActiveRecord
         ADAPTER_NAME
       end
 
+      # Adds `:array` option to the default set provided by the
+      # AbstractAdapter
+      def prepare_column_options(column, types)
+        spec = super
+        spec[:array] = 'true' if column.respond_to?(:array) && column.array
+        spec
+      end
+
+      # Adds `:array` as a valid migration key
+      def migration_keys
+        super + [:array]
+      end
+
       # Returns +true+, since this connection adapter supports prepared statement
       # caching.
       def supports_statement_cache?
@@ -494,6 +536,13 @@ module ActiveRecord
         @table_alias_length ||= query('SHOW max_identifier_length', 'SCHEMA')[0][0].to_i
       end
 
+      def add_column_options!(sql, options)
+        if options[:array] || options[:column].try(:array)
+          sql << '[]'
+        end
+        super
+      end
+
       # Set the authorized user for this session
       def session_auth=(user)
         clear_cache!
@@ -548,7 +597,7 @@ module ActiveRecord
       private
 
         def initialize_type_map
-          result = execute('SELECT oid, typname, typelem, typdelim FROM pg_type', 'SCHEMA')
+          result = execute('SELECT oid, typname, typelem, typdelim, typinput FROM pg_type', 'SCHEMA')
           leaves, nodes = result.partition { |row| row['typelem'] == '0' }
 
           # populate the leaf nodes
@@ -556,11 +605,19 @@ module ActiveRecord
             OID::TYPE_MAP[row['oid'].to_i] = OID::NAMES[row['typname']]
           end
 
+          arrays, nodes = nodes.partition { |row| row['typinput'] == 'array_in' }
+
           # populate composite types
           nodes.find_all { |row| OID::TYPE_MAP.key? row['typelem'].to_i }.each do |row|
             vector = OID::Vector.new row['typdelim'], OID::TYPE_MAP[row['typelem'].to_i]
             OID::TYPE_MAP[row['oid'].to_i] = vector
           end
+
+          # populate array types
+          arrays.find_all { |row| OID::TYPE_MAP.key? row['typelem'].to_i }.each do |row|
+            array = OID::Array.new  OID::TYPE_MAP[row['typelem'].to_i]
+            OID::TYPE_MAP[row['oid'].to_i] = array
+          end
         end
 
         FEATURE_NOT_SUPPORTED = "0A000" # :nodoc:
@@ -703,12 +760,12 @@ module ActiveRecord
         #  - ::regclass is a function that gives the id for a table name
         def column_definitions(table_name) #:nodoc:
           exec_query(<<-end_sql, 'SCHEMA').rows
-            SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a.attnotnull, a.atttypid, a.atttypmod
-              FROM pg_attribute a LEFT JOIN pg_attrdef d
-                ON a.attrelid = d.adrelid AND a.attnum = d.adnum
-             WHERE a.attrelid = '#{quote_table_name(table_name)}'::regclass
-               AND a.attnum > 0 AND NOT a.attisdropped
-             ORDER BY a.attnum
+              SELECT a.attname, format_type(a.atttypid, a.atttypmod), d.adsrc, a.attnotnull, a.atttypid, a.atttypmod
+                FROM pg_attribute a LEFT JOIN pg_attrdef d
+                  ON a.attrelid = d.adrelid AND a.attnum = d.adnum
+               WHERE a.attrelid = '#{quote_table_name(table_name)}'::regclass
+                 AND a.attnum > 0 AND NOT a.attisdropped
+               ORDER BY a.attnum
           end_sql
         end
 
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|
diff --git a/activerecord/test/cases/adapters/postgresql/array_test.rb b/activerecord/test/cases/adapters/postgresql/array_test.rb
new file mode 100644
index 0000000000..8774bf626f
--- /dev/null
+++ b/activerecord/test/cases/adapters/postgresql/array_test.rb
@@ -0,0 +1,98 @@
+# encoding: utf-8
+require "cases/helper"
+require 'active_record/base'
+require 'active_record/connection_adapters/postgresql_adapter'
+
+class PostgresqlArrayTest < ActiveRecord::TestCase
+  class PgArray < ActiveRecord::Base
+    self.table_name = 'pg_arrays'
+  end
+
+  def setup
+    @connection = ActiveRecord::Base.connection
+      @connection.transaction do
+        @connection.create_table('pg_arrays') do |t|
+          t.string 'tags', :array => true
+        end
+      end
+    @column = PgArray.columns.find { |c| c.name == 'tags' }
+  end
+
+  def teardown
+    @connection.execute 'drop table if exists pg_arrays'
+  end
+
+  def test_column
+    assert_equal :string, @column.type
+    assert @column.array
+  end
+
+  def test_type_cast_array
+    assert @column
+
+    data = '{1,2,3}'
+    oid_type  = @column.instance_variable_get('@oid_type').subtype
+    # we are getting the instance variable in this test, but in the
+    # normal use of string_to_array, it's called from the OID::Array
+    # class and will have the OID instance that will provide the type
+    # casting
+    array = @column.class.string_to_array data, oid_type
+    assert_equal(['1', '2', '3'], array)
+    assert_equal(['1', '2', '3'], @column.type_cast(data))
+
+    assert_equal([], @column.type_cast('{}'))
+    assert_equal([nil], @column.type_cast('{NULL}'))
+  end
+
+  def test_rewrite
+    @connection.execute "insert into pg_arrays (tags) VALUES ('{1,2,3}')"
+    x = PgArray.first
+    x.tags = ['1','2','3','4']
+    assert x.save!
+  end
+
+  def test_select
+    @connection.execute "insert into pg_arrays (tags) VALUES ('{1,2,3}')"
+    x = PgArray.first
+    assert_equal(['1','2','3'], x.tags)
+  end
+
+  def test_multi_dimensional
+    assert_cycle([['1','2'],['2','3']])
+  end
+
+  def test_strings_with_quotes
+    assert_cycle(['this has','some "s that need to be escaped"'])
+  end
+
+  def test_strings_with_commas
+    assert_cycle(['this,has','many,values'])
+  end
+
+  def test_strings_with_array_delimiters
+    assert_cycle(['{','}'])
+  end
+
+  def test_strings_with_null_strings
+    assert_cycle(['NULL','NULL'])
+  end
+
+  def test_contains_nils
+    assert_cycle(['1',nil,nil])
+  end
+
+  private
+  def assert_cycle array
+    # test creation
+    x = PgArray.create!(:tags => array)
+    x.reload
+    assert_equal(array, x.tags)
+
+    # test updating
+    x = PgArray.create!(:tags => [])
+    x.tags = array
+    x.save!
+    x.reload
+    assert_equal(array, x.tags)
+  end
+end
diff --git a/activerecord/test/cases/adapters/postgresql/datatype_test.rb b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
index a7f6d9c580..c7ce43d71e 100644
--- a/activerecord/test/cases/adapters/postgresql/datatype_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/datatype_test.rb
@@ -70,8 +70,8 @@ class PostgresqlDataTypeTest < ActiveRecord::TestCase
   end
 
   def test_data_type_of_array_types
-    assert_equal :string, @first_array.column_for_attribute(:commission_by_quarter).type
-    assert_equal :string, @first_array.column_for_attribute(:nicknames).type
+    assert_equal :integer, @first_array.column_for_attribute(:commission_by_quarter).type
+    assert_equal :text, @first_array.column_for_attribute(:nicknames).type
   end
 
   def test_data_type_of_tsvector_types
@@ -112,8 +112,8 @@ class PostgresqlDataTypeTest < ActiveRecord::TestCase
   end
 
   def test_array_values
-   assert_equal '{35000,21000,18000,17000}', @first_array.commission_by_quarter
-   assert_equal '{foo,bar,baz}', @first_array.nicknames
+   assert_equal [35000,21000,18000,17000], @first_array.commission_by_quarter
+   assert_equal ['foo','bar','baz'], @first_array.nicknames
   end
 
   def test_tsvector_values
@@ -170,7 +170,7 @@ class PostgresqlDataTypeTest < ActiveRecord::TestCase
   end
 
   def test_update_integer_array
-    new_value = '{32800,95000,29350,17000}'
+    new_value = [32800,95000,29350,17000]
     assert @first_array.commission_by_quarter = new_value
     assert @first_array.save
     assert @first_array.reload
@@ -182,7 +182,7 @@ class PostgresqlDataTypeTest < ActiveRecord::TestCase
   end
 
   def test_update_text_array
-    new_value = '{robby,robert,rob,robbie}'
+    new_value = ['robby','robert','rob','robbie']
     assert @first_array.nicknames = new_value
     assert @first_array.save
     assert @first_array.reload
diff --git a/activerecord/test/cases/schema_dumper_test.rb b/activerecord/test/cases/schema_dumper_test.rb
index 80d2670f94..80f46c6b08 100644
--- a/activerecord/test/cases/schema_dumper_test.rb
+++ b/activerecord/test/cases/schema_dumper_test.rb
@@ -79,9 +79,9 @@ class SchemaDumperTest < ActiveRecord::TestCase
 
   def test_arguments_line_up
     column_definition_lines.each do |column_set|
-      assert_line_up(column_set, /:default => /)
-      assert_line_up(column_set, /:limit => /)
-      assert_line_up(column_set, /:null => /)
+      assert_line_up(column_set, /default: /)
+      assert_line_up(column_set, /limit: /)
+      assert_line_up(column_set, /null: /)
     end
   end
 
@@ -278,6 +278,14 @@ class SchemaDumperTest < ActiveRecord::TestCase
       end
     end
 
+    def test_schema_dump_includes_arrays_shorthand_definition
+      output = standard_dump
+      if %r{create_table "postgresql_arrays"} =~ output
+        assert_match %r[t.text\s+"nicknames",\s+array: true], output
+        assert_match %r[t.integer\s+"commission_by_quarter",\s+array: true], output
+      end
+    end
+
     def test_schema_dump_includes_tsvector_shorthand_definition
       output = standard_dump
       if %r{create_table "postgresql_tsvectors"} =~ output