PG adapter deals with negative money values formatted with parenthesis.

Closes #11899.

activerecord/CHANGELOG.md

@@ -1,3 +1,9 @@
+*   PostgreSQL adapter recognizes negative money values formatted with
+    parentheses (eg. `($1.25) # => -1.25`)).
+    Fixes #11899.
+
+    * Yves Senn*
+
 *   Stop interpreting SQL 'string' columns as :string type because there is no
     common STRING datatype in SQL.
 

activerecord/lib/active_record/connection_adapters/postgresql/oid.rb

@@ -34,12 +34,17 @@ module ActiveRecord
         class Money < Type
           def type_cast(value)
             return if value.nil?
+            return value unless String === value
 
             # Because money output is formatted according to the locale, there are two
             # cases to consider (note the decimal separators):
             #  (1) $12,345,678.12
             #  (2) $12.345.678,12
+            # Negative values are represented as follows:
+            #  (3) -$2.55
+            #  (4) ($2.55)
 
+            value.sub!(/^\((.+)\)$/, '-\1') # (4)
             case value
             when /^-?\D+[\d,]+\.\d{2}$/  # (1)
               value.gsub!(/[^-\d.]/, '')

activerecord/test/cases/adapters/postgresql/datatype_test.rb

@@ -298,6 +298,14 @@ _SQL
     assert_equal(-567.89, @second_money.wealth)
   end
 
+  def test_money_type_cast
+    column = PostgresqlMoney.columns.find { |c| c.name == 'wealth' }
+    assert_equal(12345678.12, column.type_cast("$12,345,678.12"))
+    assert_equal(12345678.12, column.type_cast("$12.345.678,12"))
+    assert_equal(-1.15, column.type_cast("-$1.15"))
+    assert_equal(-2.25, column.type_cast("($2.25)"))
+  end
+
   def test_create_tstzrange
     skip "PostgreSQL 9.2 required for range datatypes" unless @connection.supports_ranges?
     tstzrange = Time.parse('2010-01-01 14:30:00 +0100')...Time.parse('2011-02-02 14:30:00 CDT')