Add PgIntegerArray for arrays of integers (not numerics, so no type c…

README.md

@@ -67,6 +67,26 @@ The default percision is `10` and the default scale is `0`, which is suitable fo
 
 ---
 
+### DataMapper::Property::PgIntegerArray
+
+Example:
+
+````ruby
+class MyModel
+  include DataMapper::Resource
+
+  property :id, Serial
+  property :integers, PgIntegerArray
+end
+
+m = MyModel.new(integers: [4, 8, 15, 16, 23, 42])
+m.integers
+# => [4, 8, 15, 16, 23, 42]
+````
+Use this property when you want to store an array of integers (not numerics, so no type conversions).
+
+---
+
 ### DataMapper::Property::PgHStore
 
 Example:

lib/dm-postgres-types.rb

@@ -11,6 +11,7 @@
 # lib
 require 'dm-postgres-types/property/pg_array'
 require 'dm-postgres-types/property/pg_numeric_array'
+require 'dm-postgres-types/property/pg_integer_array'
 require 'dm-postgres-types/property/pg_hstore'
 require 'dm-postgres-types/property/pg_json'
 require 'dm-postgres-types/version'
@@ -47,6 +48,7 @@ def type_map
         postgres_types = { 
           Property::PgHStore => { primitive: 'HSTORE' },
           Property::PgNumericArray => { primitive: "NUMERIC" },
+          Property::PgIntegerArray => { primitive: "INTEGER" },
           Property::PgArray => { primitive: "TEXT" },
           Property::PgJSON => { primitive: 'JSON' }
         }

lib/dm-postgres-types/property/pg_integer_array.rb

@@ -0,0 +1,20 @@
+# encoding: utf-8
+
+require 'dm-core'
+require 'dm-postgres-types/property/pg_array'
+
+module DataMapper
+  class Property
+    class PgIntegerArray < PgArray
+      def initialize(model, name, options = {})
+        super
+      end
+
+      def load(value)
+        values = super
+        values.map! { |val| val.to_i } if values
+        values
+      end
+    end
+  end
+end