Isolated PostgreSQL test into PostgreSQL folder

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

@@ -0,0 +1,29 @@
+require 'cases/helper'
+
+class TimestampTest < ActiveRecord::TestCase
+  def test_load_infinity_and_beyond
+    unless current_adapter?(:PostgreSQLAdapter)
+      return skip("only tested on postgresql")
+    end
+
+    d = Developer.find_by_sql("select 'infinity'::timestamp as updated_at")
+    assert d.first.updated_at.infinite?, 'timestamp should be infinite'
+
+    d = Developer.find_by_sql("select '-infinity'::timestamp as updated_at")
+    time = d.first.updated_at
+    assert time.infinite?, 'timestamp should be infinite'
+    assert_operator time, :<, 0
+  end
+
+  def test_save_infinity_and_beyond
+    unless current_adapter?(:PostgreSQLAdapter)
+      return skip("only tested on postgresql")
+    end
+
+    d = Developer.create!(:name => 'aaron', :updated_at => 1.0 / 0.0)
+    assert_equal(1.0 / 0.0, d.updated_at)
+
+    d = Developer.create!(:name => 'aaron', :updated_at => -1.0 / 0.0)
+    assert_equal(-1.0 / 0.0, d.updated_at)
+  end
+end

activerecord/test/cases/timestamp_test.rb

@@ -14,26 +14,6 @@ def setup
     @previously_updated_at = @developer.updated_at
   end
 
-  if current_adapter?(:PostgreSQLAdapter)
-    def test_load_infinity_and_beyond
-      d = Developer.find_by_sql("select 'infinity'::timestamp as updated_at")
-      assert d.first.updated_at.infinite?, 'timestamp should be infinite'
-
-      d = Developer.find_by_sql("select '-infinity'::timestamp as updated_at")
-      time = d.first.updated_at
-      assert time.infinite?, 'timestamp should be infinite'
-      assert_operator time, :<, 0
-    end
-
-    def test_save_infinity_and_beyond
-      d = Developer.create!(:name => 'aaron', :updated_at => 1.0 / 0.0)
-      assert_equal(1.0 / 0.0, d.updated_at)
-
-      d = Developer.create!(:name => 'aaron', :updated_at => -1.0 / 0.0)
-      assert_equal(-1.0 / 0.0, d.updated_at)
-    end
-  end
-
   def test_saving_a_changed_record_updates_its_timestamp
     @developer.name = "Jack Bauer"
     @developer.save!