2 files changed, 23 insertions, 0 deletions
diff --git a/activerecord/test/cases/adapters/mysql2/connection_test.rb b/activerecord/test/cases/adapters/mysql2/connection_test.rb
index 0b2f59b0eb..62c5abbf41 100644
--- a/activerecord/test/cases/adapters/mysql2/connection_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/connection_test.rb
@@ -4,6 +4,8 @@ require 'support/connection_helper'
 class MysqlConnectionTest < ActiveRecord::TestCase
   include ConnectionHelper
 
+  fixtures :comments
+
   def setup
     super
     @subscriber = SQLSubscriber.new
@@ -24,6 +26,17 @@ class MysqlConnectionTest < ActiveRecord::TestCase
     end
   end
 
+  def test_truncate
+    rows = ActiveRecord::Base.connection.exec_query("select count(*) from comments")
+    count = rows.first.values.first
+    assert_operator count, :>, 0
+
+    ActiveRecord::Base.connection.truncate("comments")
+    rows = ActiveRecord::Base.connection.exec_query("select count(*) from comments")
+    count = rows.first.values.first
+    assert_equal 0, count
+  end
+
   def test_no_automatic_reconnection_after_timeout
     assert @connection.active?
     @connection.update('set @@wait_timeout=1')
diff --git a/activerecord/test/cases/adapters/postgresql/connection_test.rb b/activerecord/test/cases/adapters/postgresql/connection_test.rb
index d26cda46fa..7d179944d4 100644
--- a/activerecord/test/cases/adapters/postgresql/connection_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/connection_test.rb
@@ -8,6 +8,8 @@ module ActiveRecord
     class NonExistentTable < ActiveRecord::Base
     end
 
+    fixtures :comments
+
     def setup
       super
       @subscriber = SQLSubscriber.new
@@ -20,6 +22,14 @@ module ActiveRecord
       super
     end
 
+    def test_truncate
+      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first['count'].to_i
+      assert_operator count, :>, 0
+      ActiveRecord::Base.connection.truncate("comments")
+      count = ActiveRecord::Base.connection.execute("select count(*) from comments").first['count'].to_i
+      assert_equal 0, count
+    end
+
     def test_encoding
       assert_not_nil @connection.encoding
     end